View source for Jurassic

{{Short description|Second period of the Mesozoic Era}}
{{Infobox geologic timespan
| name                         = {{color|white|Jurassic}}
| color                        = Jurassic
| top_bar                      = 
| time_start                   = 201.4
| time_start_uncertainty       = 0.2
| time_end                     = 143.1
| time_end_uncertainty         = 0.6
| image_map                    = Mollweide Paleographic Map of Earth, 170 Ma (Bajocian Age).png 
| caption_map                  = A map of Earth as it appeared 170 million years ago during the Middle Jurassic Epoch
| image_outcrop                =
| caption_outcrop              =
| image_art                    =
| caption_art                  =
<!--Chronology-->
| timeline                     = Jurassic
<!--Etymology-->
| name_formality               = Formal
| name_accept_date             =
| alternate_spellings          =
| synonym1                     =
| synonym1_coined              =
| synonym2                     =
| synonym2_coined              =
| synonym3                     =
| synonym3_coined              =
| nicknames                    =
| former_names                 =
| proposed_names               =
<!--Usage Information--> 
| usage                        = Global ([[International Commission on Stratigraphy|ICS]])
| timescales_used              = ICS Time Scale
| formerly_used_by             =
| not_used_by                  =
<!--Definition-->
| chrono_unit                  = Period
| strat_unit                   = System
| proposed_by                  =
| timespan_formality           = Formal
| lower_boundary_def           = First appearance of the [[ammonite]] ''[[Psiloceras|Psiloceras spelae tirolicum]]''.
| lower_gssp_location          = Kuhjoch section, [[Karwendel|Karwendel mountains]], [[Northern Calcareous Alps]], Austria
| lower_gssp_coords            = {{Coord|47.4839|N|11.5306|E|display=inline}}
| lower_gssp_accept_date       = 2010
| upper_boundary_def           = Not formally defined
| upper_def_candidates         = 
*Magnetic—base of [[Chronozone|Chron]] M18r
*Base of [[Calpionellid]] zone B
*[[First appearance datum|FAD]] of [[ammonite]] ''[[Berriasella|Berriasella jacobi]]''
| upper_gssp_candidates        = None

<!--Atmospheric and Climatic Data-->
| sea_level                    =
}}
The '''Jurassic''' ({{IPAc-en|dʒ|ʊ|ˈ|r|æ|s|ɪ|k}} {{respell|juurr|ASS|ik}}<ref>{{Cite web |date=2024-04-17 |title=Dictionary.com {{!}} Meanings & Definitions of English Words |url=https://www.dictionary.com/browse/jurassic |access-date=2024-04-18 |website=Dictionary.com |language=en}}</ref>) is a [[Geological period|geologic period]] and [[System (stratigraphy)|stratigraphic system]] that spanned from the end of the [[Triassic]] Period {{Period start|Jurassic}} Ma (million years ago) to the beginning of the [[Cretaceous]] Period, 143.1 Ma. The Jurassic constitutes the second and middle period of the [[Mesozoic|Mesozoic Era]] as well as the eighth period of the [[Phanerozoic|Phanerozoic Eon]] and is named after the [[Jura Mountains]], where [[limestone]] strata from the period were first identified.

The start of the Jurassic was marked by the major [[Triassic–Jurassic extinction event]], associated with the eruption of the [[Central Atlantic magmatic province|Central Atlantic Magmatic Province]] (CAMP). The beginning of the [[Toarcian]] Age started around 183 Ma and is marked by the [[Toarcian Oceanic Anoxic Event]], a global episode of [[Anoxic event|oceanic anoxia]], [[ocean acidification]], and elevated global temperatures associated with extinctions, likely caused by the eruption of the [[Karoo-Ferrar|Karoo-Ferrar large igneous provinces]]. The end of the Jurassic, however, has no clear, definitive boundary with the Cretaceous and is the only boundary between geological periods to remain formally undefined.

By the beginning of the Jurassic, the [[supercontinent]] [[Pangaea]] had begun [[rift]]ing into two landmasses: [[Laurasia]] to the north and [[Gondwana]] to the south. The climate of the Jurassic was warmer than the present, and there were no [[ice caps]]. Forests grew close to the poles, with large arid expanses in the lower latitudes.

On land, the fauna transitioned from the Triassic fauna, dominated jointly by [[Dinosauromorpha|dinosauromorph]] and [[pseudosuchia]]n [[archosaur]]s, to one dominated by [[dinosaur]]s alone. The first [[Stem group|stem-group]] birds appeared during the Jurassic, evolving from a branch of [[theropod]] dinosaurs. Other major events include the appearance of the earliest [[crab]]s and modern [[frog]]s, [[salamander]]s and [[lizard]]s. [[Mammaliaformes]], one of the few [[Cynodontia|cynodont]] lineages to survive the end of the Triassic, continued to diversify throughout the period, with the Jurassic seeing the emergence of the first [[crown group]] [[mammal]]s. [[Crocodylomorpha|Crocodylomorphs]] made the transition from a terrestrial to an aquatic life. The oceans were inhabited by [[marine reptiles]] such as [[Ichthyosauria|ichthyosaur]]s and [[plesiosaur]]s, while [[pterosaur]]s were the dominant flying [[vertebrates]]. Modern sharks and rays first appeared and diversified during the period, while the first known crown-group [[teleost]] fish (the dominant group of modern fish) appeared near the end of the period. The flora was dominated by [[fern]]s and [[gymnosperm]]s, including [[conifer]]s, of which many modern groups made their first appearance during the period, as well as other groups like the extinct [[Bennettitales]].
{{TOC limit|3}}

==Etymology and history==
[[File:Alexandre Brongniart.jpg|thumb|left|Portrait of [[Alexandre Brongniart]], who coined the term "Jurassic"|alt=alt=A realistic black-and-white portrait of Brongniart, who is clean shaven with a full head of hair. He is dressed in a formal jacket]]
The [[chronostratigraphy|chronostratigraphic]] term "Jurassic" is linked to the [[Jura Mountains]], a forested [[mountain range]] that mainly follows the [[France–Switzerland border]]. The name "Jura" is derived from the [[Celtic languages|Celtic]] root {{lang|cel|*jor}} via [[Gaulish]] ''*iuris'' "wooded mountain", which was borrowed into [[Latin]] as a name of a place and evolved into ''Juria'' and finally ''Jura''.{{citation needed |date=November 2025}}

During a tour of the region in 1795, German [[naturalist]] [[Alexander von Humboldt]] recognized [[Carbonate rock|carbonate]] deposits within the Jura Mountains as [[Geology of the Jura Massif|geologically]] distinct from the [[Triassic]] aged [[Muschelkalk]] of southern [[Germany]], but he erroneously concluded that they were older. He then named them {{lang|de|Jura-Kalkstein}} ('Jura limestone') in 1799.<ref name="Ogg-2012" />

In 1829, the French naturalist [[Alexandre Brongniart]] published a book entitled ''Description of the Terrains that Constitute the Crust of the Earth or Essay on the Structure of the Known Lands of the Earth.'' In this book, Brongniart used the phrase ''terrains jurassiques'' when correlating the "Jura-Kalkstein" of Humboldt with similarly aged [[Oolite|oolitic limestones]] in Britain, thus coining and publishing the term "Jurassic".<ref>{{cite book |last=Brongniart |first=Alexandre |author-link=Alexandre Brongniart |title=Tableau des terrains qui composent l'écorce du globe ou essai sur la structure de la partie connue de la terre |publisher=F.G. Levrault |location=Strasbourg, France |year=1829 |url=https://gallica.bnf.fr/ark:/12148/bpt6k255061/f1.image |language=fr |via=Gallica|trans-title=Description of the Terrains that Constitute the Crust of the Earth or Essay on the Structure of the Known Lands of the Earth}}  From p. 221, footnote 2:  ''"Souvent aussi calcaire oolithique moyen ou principal (great oolithe); mais le nom de terrains jurassiques nous paroît préférable […] analogue à celle de la chaîne du Jura."'' (Often also middle or principal oolitic limestone (great oolithe); but the name of "Jurassic terrains" seems to us preferable, because it is more general, because it indicates a terrain composed of different rocks, being in a geognostic position analogous to that of the Jura chain.)</ref><ref name="Ogg-2012" />

The German geologist [[Christian Leopold von Buch|Leopold von Buch]] in 1839 established the three-fold division of the Jurassic, originally named from oldest to the youngest: the [[Black Jurassic]], [[Brown Jurassic]], and [[White Jurassic]].<ref>von Buch, L., 1839. Über den Jura in Deutschland. Der Königlich Preussischen Akademie der Wissenschaften, Berlin, p. 87.</ref> The term "[[Lias Group|Lias]]" had previously been used for strata of equivalent age to the Black Jurassic in England by [[William Conybeare (geologist)|William Conybeare]] and [[William Phillips (geologist)|William Phillips]] in 1822. William Phillips, the geologist, worked with William Conybeare to find out more about the Black Jurassic in England.

The French [[palaeontologist]] [[Alcide d'Orbigny]] in papers between 1842 and 1852 divided the Jurassic into ten stages based on [[ammonite]] and other fossil assemblages in England and France, of which seven are still used, but none has retained its original definition. The German geologist and palaeontologist [[Friedrich August von Quenstedt]] in 1858 divided the three series of von Buch in the [[Swabian Jura]] into six subdivisions defined by ammonites and other fossils.

The German palaeontologist [[Albert Oppel]] in his studies between 1856 and 1858 altered d'Orbigny's original scheme and further subdivided the stages into [[Biostratigraphy|biostratigraphic]] zones, based primarily on ammonites. Most of the modern stages of the Jurassic were formalized at the Colloque du Jurassique à Luxembourg in 1962.<ref name="Ogg-2012" />

==Geology==
The Jurassic Period is divided into three [[Epoch (geology)|epochs]]: Early, Middle, and Late. Similarly, in [[stratigraphy]], the Jurassic is divided into the [[Lower Jurassic]], [[Middle Jurassic]], and [[Upper Jurassic]] [[Series (stratigraphy)|series]]. Geologists divide the rocks of the Jurassic into a [[Stratigraphy|stratigraphic]] set of units called [[Stage (stratigraphy)|stages]], each formed during corresponding time intervals called ages.

Stages can be defined globally or regionally. For global stratigraphic correlation, the [[International Commission on Stratigraphy]] (ICS) ratify global stages based on a [[Global Boundary Stratotype Section and Point]] (GSSP) from a single [[Formation (geology)|formation]] (a [[stratotype]]) identifying the lower boundary of the stage.<ref name="Ogg-2012" /> The ages of the Jurassic from youngest to oldest are as follows:<ref>Cohen, K.M., Finney, S.C., Gibbard, P.L. & Fan, J.-X. (2013; updated) [https://stratigraphy.org/ICSchart/ChronostratChart2024-12.pdf The ICS International Chronostratigraphic Chart]. Episodes 36: 199–204.</ref>

{|
|Series/epoch
|Stage/age
|Lower boundary
|-
|style="background-color: {{period color|Early Cretaceous}};" |  [[Early Cretaceous]]
|style="background-color: {{period color|Berriasian}};" | [[Berriasian]]
|143.1 ± 0.6 Ma
|-
| rowspan="3" style="background-color: {{period color|Late Jurassic}};" , | '''[[Late Jurassic|Upper/Late Jurassic]]'''
| style="background-color: {{period color|Tithonian}};" | [[Tithonian]]
| 149.2 ± 0.7 Ma
|-
| style="background-color: {{period color|Kimmeridgian}};" | [[Kimmeridgian]]
| 154.8 ± 0.8 Ma
|-
| style="background-color: {{period color|Oxfordian}};" | [[Oxfordian stage|Oxfordian]]
| 161.5 ± 1.0 Ma
|-
| rowspan="4" style="background-color: {{period color|Middle Jurassic}}" , |'''[[Middle Jurassic]]'''
| style="background-color: {{period color|Callovian}};" | [[Callovian]]
| 165.3 ± 1.1 Ma
|-
| style="background-color: {{period color|Bathonian}};" | [[Bathonian]]
| 168.2 ± 1.2 Ma
|-
| style="background-color: {{period color|Bajocian}};" | [[Bajocian]]
| 170.9 ± 0.8 Ma
|-
| style="background-color: {{period color|Aalenian}};" | [[Aalenian]]
| 174.7 ± 0.8 Ma
|-
| rowspan="4" style="background-color: {{period color|Early Jurassic}} " , |'''[[Early Jurassic|Lower/Early Jurassic]]'''
| style="background-color: {{period color|Toarcian}};" | [[Toarcian]]
| 184.2 ± 0.3 Ma
|-
| style="background-color: {{period color|Pliensbachian}};" | [[Pliensbachian]]
| 192.9 ± 0.3 Ma
|-
| style="background-color: {{period color|Sinemurian}};" | [[Sinemurian]]
| 199.5 ± 0.3 Ma
|-
| style="background-color: {{period color|Hettangian}};" | [[Hettangian]]
| 201.4 ± 0.2 Ma
|}

=== Stratigraphy ===
[[File:Folding Gasteretal.jpg|thumb|Folded Lower Jurassic limestone layers of the Doldenhorn [[nappe]] at [[Kander (Switzerland)|Gasteretal]], Switzerland]]
[[File:Fm Lajas Maquina Cura.jpg|thumb|Middle Jurassic strata in [[Neuquén Province]], Argentina]]
[[File:Tidwell Member of the Morrison Formation over Wanakah Formation (Jurassic; roadcut near Artists Point, Colorado National Monument, Colorado, USA) 1 (23644153939).jpg|thumb|Tidwell Member of the Morrison Formation (Upper Jurassic), Colorado]]

Jurassic stratigraphy is primarily based on the use of ammonites as [[Biostratigraphy#Index fossils|index fossils]]. The [[first appearance datum]] of specific ammonite [[Taxon|taxa]] is used to mark the beginnings of stages, as well as smaller timespans within stages, referred to as "ammonite zones"; these, in turn, are also sometimes subdivided further into subzones. Global stratigraphy is based on standard European ammonite zones, with other regions being calibrated to the European successions.<ref name="Ogg-2012" /> [[File:Aalenian_GSSP_-_Golden_spike_ceremony_-_Fuentelsaz,_Guadalajara,_Spain_08.jpg|thumb|Base Aalenian GSSP at [[Fuentelsaz]]]]

==== Early Jurassic ====
The oldest part of the Jurassic Period has historically been referred to as the Lias or Liassic, roughly equivalent in extent to the Early Jurassic, but also including part of the preceding [[Rhaetian]]. The Hettangian Stage was named by Swiss palaeontologist [[Eugène Renevier]] in 1864 after [[Hettange-Grande]] in north-eastern France.<ref name="Ogg-2012" /> The GSSP for the base of the Hettangian is located at the Kuhjoch Pass, [[Karwendel|Karwendel Mountains]], [[Northern Limestone Alps|Northern Calcareous Alps]], Austria; it was ratified in 2010. The beginning of the Hettangian, and thus the Jurassic as a whole, is marked by the [[First appearance datum|first appearance]] of the ammonite ''[[Psiloceras|Psiloceras spelae tirolicum]]'' in the [[Kendlbach Formation]] exposed at Kuhjoch.<ref>{{Cite journal|last1=Hillebrandt|first1=A.v.|last2=Krystyn|first2=L.|last3=Kürschner|first3=W.M.|last4=Bonis|first4=N.R.|last5=Ruhl|first5=M.|last6=Richoz|first6=S.|last7=Schobben|first7=M. A. N.|last8=Urlichs|first8=M.|last9=Bown|first9=P.R.|last10=Kment|first10=K.|last11=McRoberts|first11=C.A.|date=2013-09-01|title=The Global Stratotype Sections and Point (GSSP) for the base of the Jurassic System at Kuhjoch (Karwendel Mountains, Northern Calcareous Alps, Tyrol, Austria)|journal=Episodes|language=en|volume=36|issue=3|pages=162–198|doi=10.18814/epiiugs/2013/v36i3/001|issn=0705-3797|doi-access=free}}</ref> The base of the Jurassic was previously defined as the first appearance of ''Psiloceras planorbis'' by Albert Oppel in 1856–58, but this was changed as the appearance was seen as too localised an event for an international boundary.<ref name="Ogg-2012" />

The Sinemurian Stage was first defined and introduced into scientific literature by Alcide d'Orbigny in 1842. It takes its name from the French town of [[Semur-en-Auxois]], near [[Dijon]]. The original definition of Sinemurian included what is now the Hettangian. The GSSP of the Sinemurian is located at a cliff face north of the hamlet of [[East Quantoxhead]], 6 kilometres east of [[Watchet]], [[Somerset]], [[England]], within the [[Blue Lias]], and was ratified in 2000. The beginning of the Sinemurian is defined by the first appearance of the ammonite ''[[Vermiceras|Vermiceras quantoxense]].''<ref name="Ogg-2012">{{Citation|last1=Ogg|first1=J.G.|title=Jurassic|date=2012|url=https://linkinghub.elsevier.com/retrieve/pii/B9780444594259000263|work=The Geologic Time Scale|pages=731–791|publisher=Elsevier|language=en|doi=10.1016/b978-0-444-59425-9.00026-3|isbn=978-0-444-59425-9|access-date=2020-12-05|last2=Hinnov|first2=L.A.|last3=Huang|first3=C.|url-access=subscription}}</ref><ref>{{Cite journal|last1=Bloos|first1=Gert|last2=Page|first2=Kevin N.|date=2002-03-01|title=Global Stratotype Section and Point for base of the Sinemurian Stage (Lower Jurassic)|journal=Episodes|volume=25|issue=1|pages=22–28|doi=10.18814/epiiugs/2002/v25i1/003|issn=0705-3797|doi-access=free}}</ref>

Albert Oppel in 1858 named the Pliensbachian Stage after the hamlet of [[Pliensbach]] in the community of [[Zell unter Aichelberg]] in the [[Swabian Alb]], near [[Stuttgart]], Germany. The GSSP for the base of the Pliensbachian is found at the Wine Haven locality in [[Robin Hood's Bay]], [[Yorkshire]], England, in the [[Redcar Mudstone Formation]], and was ratified in 2005. The beginning of the Pliensbachian is defined by the first appearance of the ammonite ''[[Bifericeras|Bifericeras donovani]]''.<ref>{{Cite journal|last1=Meister|first1=Christian|last2=Aberhan|first2=Martin|last3=Blau|first3=Joachim|last4=Dommergues|first4=Jean-Louis|last5=Feist-Burkhardt|first5=Susanne|last6=Hailwood|first6=Ernie A.|last7=Hart|first7=Malcom|last8=Hesselbo|first8=Stephen P.|last9=Hounslow|first9=Mark W.|last10=Hylton|first10=Mark|last11=Morton|first11=Nicol|date=2006-06-01|title=The Global Boundary Stratotype Section and Point (GSSP) for the base of the Pliensbachian Stage (Lower Jurassic), Wine Haven, Yorkshire, UK|journal=Episodes|volume=29|issue=2|pages=93–106|doi=10.18814/epiiugs/2006/v29i2/003|issn=0705-3797|doi-access=free}}</ref>

The village [[Thouars]] (Latin: ''Toarcium''), just south of [[Saumur]] in the [[Loire Valley]] of [[France]], lends its name to the Toarcian Stage. The Toarcian was named by Alcide d'Orbigny in 1842, with the original locality being Vrines quarry around 2&nbsp;km northwest of Thouars. The GSSP for the base of the Toarcian is located at [[Peniche, Portugal]], and was ratified in 2014. The boundary is defined by the first appearance of ammonites belonging to the subgenus ''[[Dactylioceras]]'' [[Dactylioceras|(''Eodactylites'')]]''.''<ref>{{Cite journal|last1=Rocha|first1=Rogério Bordalo da|last2=Mattioli|first2=Emanuela|last3=Duarte|first3=Luís Vítor|last4=Pittet|first4=Bernard|last5=Elmi|first5=Serge|last6=Mouterde|first6=René|last7=Cabral|first7=Maria Cristina|last8=Comas-Rengifo|first8=Maria José|last9=Gómez|first9=Juan José|last10=Goy|first10=António|last11=Hesselbo|first11=Stephen P.|date=2016-09-01|title=Base of the Toarcian Stage of the Lower Jurassic defined by the Global Boundary Stratotype Section and Point (GSSP) at the Peniche section (Portugal)|journal=Episodes|language=en|volume=39|issue=3|pages=460–481|doi=10.18814/epiiugs/2016/v39i3/99741|s2cid=131791652 |issn=0705-3797|doi-access=free|hdl=10261/140775|hdl-access=free}}</ref>

==== Middle Jurassic ====
The Aalenian is named after the city of [[Aalen]] in Germany. The Aalenian was defined by Swiss geologist [[Karl Mayer-Eymar]] in 1864. The lower boundary was originally between the dark clays of the Black Jurassic and the overlying clayey sandstone and [[Iron|ferruginous]] oolite of the Brown Jurassic sequences of southwestern Germany.<ref name="Ogg-2012" /> The GSSP for the base of the Aalenian is located at [[Fuentelsaz]] in the [[Sistema Ibérico|Iberian range]] near [[Guadalajara, Spain]], and was ratified in 2000. The base of the Aalenian is defined by the first appearance of the ammonite ''[[Leioceras|Leioceras opalinum]]''.<ref>{{Cite journal|last1=Barrón|first1=Eduardo|last2=Ureta|first2=Soledad|last3=Goy|first3=Antonio|last4=Lassaletta|first4=Luis|date=August 2010|title=Palynology of the Toarcian–Aalenian Global Boundary Stratotype Section and Point (GSSP) at Fuentelsaz (Lower–Middle Jurassic, Iberian Range, Spain)|url=https://linkinghub.elsevier.com/retrieve/pii/S0034666710000898|journal=Review of Palaeobotany and Palynology|language=en|volume=162|issue=1|pages=11–28|doi=10.1016/j.revpalbo.2010.04.003|bibcode=2010RPaPa.162...11B }}</ref>

Alcide d'Orbigny in 1842 named the Bajocian Stage after the town of [[Bayeux]] (Latin: ''Bajoce'') in Normandy, France. The GSSP for the base of the Bajocian is located in the Murtinheira section at [[Cabo Mondego]], Portugal; it was ratified in 1997. The base of the Bajocian is defined by the first appearance of the ammonite ''[[Hyperlioceras|Hyperlioceras mundum]].''<ref>{{Cite journal|last1=Pavia|first1=G.|last2=Enay|first2=R.|date=1997-03-01|title=Definition of the Aalenian-Bajocian Stage boundary|journal=Episodes|volume=20|issue=1|pages=16–22|doi=10.18814/epiiugs/1997/v20i1/004|issn=0705-3797|doi-access=free}}</ref>

The Bathonian is named after the city of [[Bath, Somerset|Bath]], England, introduced by Belgian geologist [[Jean Baptiste Julien d'Omalius d'Halloy|d'Omalius d'Halloy]] in 1843, after an incomplete section of oolitic limestones in several quarries in the region. The GSSP for the base of the Bathonian is Ravin du Bès, Bas-Auran area, [[Alpes-de-Haute-Provence|Alpes de Haute Provence]], France; it was ratified in 2009. The base of the Bathonian is defined by the first appearance of the ammonite ''[[Gonolkites|Gonolkites convergens]]'', at the base of the [[Zigzagiceras|''Zigzagiceras zigzag'']] ammonite zone''.''<ref>{{cite journal|last1=López|first1=Fernández|last2=Rafael|first2=Sixto|last3=Pavia|first3=Giulio|last4=Erba|first4=Elisabetta|last5=Guiomar|first5=Myette|last6=Paiva Henriques|first6=María Helena|last7=Lanza|first7=Roberto|last8=Mangold|first8=Charles|last9=Morton|first9=Nicol|last10=Olivero|first10=Davide|last11=Tiraboschi|first11=Daniele|date=2009|title=The Global Boundary Stratotype Section and Point (GSSP) for base of the Bathonian Stage (Middle Jurassic), Ravin du Bès Section, SE France|journal=Episodes|volume=32|issue=4|pages=222–248|doi=10.18814/epiiugs/2009/v32i4/001|doi-access=free |s2cid=51754708 |df=dmy}}</ref>

The Callovian is derived from the [[Latinisation of names|Latinized]] name of the village of [[Kellaways]] in [[Wiltshire]], England, and was named by Alcide d'Orbigny in 1852, originally the base at the contact between the [[Forest Marble Formation]] and the [[Cornbrash Formation]]. However, this boundary was later found to be within the upper part of the Bathonian.<ref name="Ogg-2012" /> The base of the Callovian does not yet have a certified GSSP. The working definition for the base of the Callovian is the first appearance of ammonites belonging to the genus ''[[Kepplerites]].<ref name="jurassic.stratigraphy.org">{{Cite web|title=International Commission on Stratigraphy-Subcommission on Jurassic Stratigraphy|url=https://jurassic.stratigraphy.org/our-work|access-date=2021-04-09|website=jurassic.stratigraphy.org}}</ref>''

==== Late Jurassic ====
The Oxfordian is named after the city of [[Oxford]] in England and was named by Alcide d'Orbigny in 1844 in reference to the [[Oxford Clay]]. The base of the Oxfordian lacks a defined GSSP. [[William Joscelyn Arkell|W. J. Arkell]] in studies in 1939 and 1946 placed the lower boundary of the Oxfordian as the first appearance of the ammonite ''[[Quenstedtoceras|Quenstedtoceras mariae]]'' (then placed in the genus ''[[Vertumniceras]]''). Subsequent proposals have suggested the first appearance of ''[[Cardioceras|Cardioceras redcliffense]]'' as the lower boundary.<ref name="Ogg-2012" /><ref name="jurassic.stratigraphy.org" />

[[Image:Egmont bight from freshwater steps promontory dorset.jpg|right|thumb|[[Kimmeridge Clay]] at [[Egmont Bight]] in the [[Jurassic Coast]], southern England]]
The village of [[Kimmeridge]] on the coast of [[Dorset]], England, is the origin of the name of the Kimmeridgian. The stage was named by Alcide d'Orbigny in 1842 in reference to the [[Kimmeridge Clay]]. The GSSP for the base of the Kimmeridgian is the Flodigarry section at [[Staffin|Staffin Bay]] on the [[Isle of Skye]], Scotland,<ref>{{Cite journal|last=BARSKI|first=Marcin|date=2018-09-06|title=Dinoflagellate cyst assemblages across the Oxfordian/Kimmeridgian boundary (Upper Jurassic) at Flodigarry, Staffin Bay, Isle of Skye, Scotland – a proposed GSSP for the base of the Kimmeridgian|journal=Volumina Jurassica|volume=XV|issue=1|pages=51–62|doi=10.5604/01.3001.0012.4594|doi-broken-date=20 August 2025 |s2cid=133861564|issn=1731-3708}}</ref> which was ratified in 2021. The boundary is defined by the first appearance of ammonites marking the boreal Bauhini Zone and the subboreal Baylei Zone.<ref name="jurassic.stratigraphy.org" />

The Tithonian was introduced in scientific literature by Albert Oppel in 1865. The name Tithonian is unusual in geological stage names because it is derived from [[Greek mythology]] rather than a place name. [[Tithonus]] was the son of [[Laomedon]] of [[Troy]] and fell in love with [[Eos]], the Greek goddess of [[dawn]]. His name was chosen by Albert Oppel for this [[Stratigraphy|stratigraphical]] stage because the Tithonian finds itself hand in hand with the dawn of the Cretaceous. The base of the Tithonian currently lacks a GSSP.<ref name="Ogg-2012" /> The working definition for the base of the Tithonian is the first appearance of the ammonite genus ''[[Gravesia (ammonite)|Gravesia]]''.<ref name="jurassic.stratigraphy.org" />

The upper boundary of the Jurassic is currently undefined, and the Jurassic–Cretaceous boundary is currently the only system boundary to lack a defined GSSP. Placing a GSSP for this boundary has been difficult because of the strong regionality of most biostratigraphic markers, and lack of any [[Chemostratigraphy|chemostratigraphic]] events, such as [[isotope]] excursions (large sudden changes in [[Stable isotope ratio|ratios of isotopes]]), that could be used to define or correlate a boundary. [[Calpionellid]]s, an enigmatic group of [[plankton]]ic [[protist]]s with urn-shaped calcitic [[Test (biology)|tests]] briefly abundant during the latest Jurassic to earliest Cretaceous, have been suggested to represent the most promising candidates for fixing the Jurassic–Cretaceous boundary<ref>{{Cite journal|last=WIMBLEDON|first=William A.P.|date=2017-12-27|title=Developments with fixing a Tithonian/Berriasian (J/K) boundary|url=https://www.researchgate.net/publication/321670503|journal=Volumina Jurassica|volume=15 |issue=1 |pages=107–112|doi=10.5604/01.3001.0010.7467|doi-broken-date=20 August 2025 |issn=1731-3708}}</ref> In particular, the first appearance ''[[Calpionella|Calpionella alpina]],'' co-inciding with the base of the eponymous Alpina subzone, has been proposed as the definition of the base of the Cretaceous.<ref>{{Cite journal|last1=Wimbledon|first1=William A.P.|last2=Rehakova|first2=Daniela|last3=Svobodová|first3=Andrea|last4=Schnabl|first4=Petr|last5=Pruner|first5=Petr|last6=Elbra|first6=Tiiu|last7=Šifnerová|first7=Kristýna|last8=Kdýr|first8=Šimon|last9=Frau|first9=Camille|last10=Schnyder|first10=Johann|last11=Galbrun|first11=Bruno|date=2020-02-11|title=Fixing a J/K boundary: A comparative account of key Tithonian–Berriasian profiles in the departments of Drôme and Hautes-Alpes, France|url=https://www.sav.sk/index.php?lang=sk&doc=journal-list&part=article_response_page&journal_article_no=18100|journal=Geologica Carpathica|volume=71|issue=1|doi=10.31577/GeolCarp.71.1.3|s2cid=213694912|doi-access=free|bibcode=2020GCarp..71..1.3W }}</ref> The working definition for the boundary has often been placed as the first appearance of the ammonite ''[[Strambergella jacobi]],'' formerly placed in the genus ''[[Berriasella]]'', but its use as a stratigraphic indicator has been questioned, as its first appearance does not correlate with that of ''C. alpina''.<ref>{{Cite journal|last1=Frau|first1=Camille|last2=Bulot|first2=Luc G.|last3=Reháková|first3=Daniela|last4=Wimbledon|first4=William A.P.|last5=Ifrim|first5=Christina|date=November 2016|title=Revision of the ammonite index species Berriasella jacobi Mazenot, 1939 and its consequences for the biostratigraphy of the Berriasian Stage|url=http://linkinghub.elsevier.com/retrieve/pii/S0195667116301057|journal=Cretaceous Research|language=en|volume=66|pages=94–114|doi=10.1016/j.cretres.2016.05.007|bibcode=2016CrRes..66...94F |url-access=subscription}}</ref>

=== Mineral and hydrocarbon deposits ===
The Kimmeridge Clay and equivalents are the major [[source rock]] for the [[North Sea oil]].<ref name="USGS">{{Cite web|last=Gautier D.L.|year=2005|title=Kimmeridgian Shales Total Petroleum System of the North Sea Graben Province|url=https://pubs.usgs.gov/bul/2204/c/pdf/B2204C.pdf|access-date=2 November 2018|publisher=United States Geological Survey}}</ref> The Arabian Intrashelf Basin, deposited during the Middle and Late Jurassic, is the setting of the world's largest oil reserves, including the [[Ghawar Field]], the world's largest oil field.<ref>{{Cite journal|last=Wilson|first=A. O.|date=2020|title=Chapter 1 Introduction to the Jurassic Arabian Intrashelf Basin|journal=Geological Society, London, Memoirs|language=en|volume=53|issue=1|pages=1–19|doi=10.1144/M53.1|s2cid=226967035|issn=0435-4052|doi-access=free}}</ref> The Jurassic-aged Sargelu<ref>{{Cite journal|last=Abdula|first=Rzger A.|date=August 2015|title=Hydrocarbon potential of Sargelu Formation and oil-source correlation, Iraqi Kurdistan|url=http://link.springer.com/10.1007/s12517-014-1651-0|journal=Arabian Journal of Geosciences|language=en|volume=8|issue=8|pages=5845–5868|doi=10.1007/s12517-014-1651-0|bibcode=2015ArJG....8.5845A |s2cid=129120960|issn=1866-7511|url-access=subscription}}</ref> and Naokelekan formations<ref>{{Cite journal|last1=Soran University|last2=Abdula|first2=Rzger A.|date=2016-10-16|title=Source Rock Assessment of Naokelekan Formation in Iraqi Kurdistan|journal=Journal of Zankoy Sulaimani – Part A|volume=19|issue=1|pages=103–124|doi=10.17656/jzs.10589|doi-access=free}}</ref> are major source rocks for [[Oil reserves in Iraq|oil in Iraq]]. Over 1500 gigatons of Jurassic coal reserves are found in north-west China, primarily in the [[Turpan Depression|Turpan-Hami Basin]] and the [[Ordos Plateau|Ordos Basin]].<ref>{{Cite journal|last1=Ao|first1=Weihua|last2=Huang|first2=Wenhui|last3=Weng|first3=Chengmin|last4=Xiao|first4=Xiuling|last5=Liu|first5=Dameng|last6=Tang|first6=Xiuyi|last7=Chen|first7=Ping|last8=Zhao|first8=Zhigen|last9=Wan|first9=Huan|last10=Finkelman|first10=Robert B.|date=January 2012|title=Coal petrology and genesis of Jurassic coal in the Ordos Basin, China|journal=Geoscience Frontiers|language=en|volume=3|issue=1|pages=85–95|doi=10.1016/j.gsf.2011.09.004|bibcode=2012GeoFr...3...85A |doi-access=free}}</ref>

=== Impact structures ===
Major impact structures include the [[Morokweng impact structure]], a 70&nbsp;km diameter impact structure buried beneath the Kalahari desert in northern South Africa. The impact is dated to the Tithonian, approximately 146.06 ± 0.16 Ma.<ref>{{Cite journal|last1=Kenny|first1=Gavin G.|last2=Harrigan|first2=Claire O.|last3=Schmitz|first3=Mark D.|last4=Crowley|first4=James L.|last5=Wall|first5=Corey J.|last6=Andreoli|first6=Marco A. G.|last7=Gibson|first7=Roger L.|last8=Maier|first8=Wolfgang D.|date=2021-08-01|title=Timescales of impact melt sheet crystallization and the precise age of the Morokweng impact structure, South Africa|journal=Earth and Planetary Science Letters|language=en|volume=567|article-number=117013|doi=10.1016/j.epsl.2021.117013|bibcode=2021E&PSL.56717013K |s2cid=235666971|issn=0012-821X|doi-access=free}}</ref> Another major structure is the [[Puchezh-Katunki crater]], 40 kilometres in diameter, buried beneath [[Nizhny Novgorod Oblast]] in western Russia. The impact has been dated to the Sinemurian, 195.9 ± 1.0 Ma.<ref>{{Cite journal|last1=Holm-Alwmark|first1=Sanna|last2=Jourdan|first2=Fred|last3=Ferrière|first3=Ludovic|last4=Alwmark|first4=Carl|last5=Koeberl|first5=Christian|date=15 May 2021|title=Resolving the age of the Puchezh-Katunki impact structure (Russia) against alteration and inherited 40Ar* – No link with extinctions|journal=Geochimica et Cosmochimica Acta|language=en|volume=301|pages=116–140|doi=10.1016/j.gca.2021.03.001|bibcode=2021GeCoA.301..116H |s2cid=233620694 |doi-access=free}}</ref>

== Paleogeography and tectonics ==
[[File:Mollweide Paleographic Map of Earth, 190 Ma (Pliensbachian Age).png|thumb|Map of geography during the Early Jurassic, around 190 million years ago|270x270px]]
At the beginning of the Jurassic, all of the world's major landmasses were coalesced into the [[supercontinent]] [[Pangaea]], which during the Early Jurassic began to break up into northern supercontinent [[Laurasia]] and the southern supercontinent [[Gondwana]].<ref name="Scotese-2021">{{Cite journal|last=Scotese|first=Christopher R.|date=2021-05-30|title=An Atlas of Phanerozoic Paleogeographic Maps: The Seas Come In and the Seas Go Out|journal=[[Annual Review of Earth and Planetary Sciences]]|language=en|volume=49|issue=1|pages=679–728|doi=10.1146/annurev-earth-081320-064052|bibcode=2021AREPS..49..679S|s2cid=233708826|issn=0084-6597|doi-access=free}}</ref> The rifting between North America and Africa was the first to initiate, beginning in the early Jurassic, associated with the emplacement of the [[Central Atlantic magmatic province|Central Atlantic Magmatic Province]].<ref name="Frizon de Lamotte-2015">{{Cite journal|last1=Frizon de Lamotte|first1=Dominique|last2=Fourdan|first2=Brendan|last3=Leleu|first3=Sophie|last4=Leparmentier|first4=François|last5=de Clarens|first5=Philippe|date=24 April 2015|title=Style of rifting and the stages of Pangea breakup|journal=[[Tectonics (journal)|Tectonics]]|language=en|volume=34|issue=5|pages=1009–1029|doi=10.1002/2014TC003760|bibcode=2015Tecto..34.1009F|s2cid=135409359 |doi-access=free}}</ref>
[[File:Toarcian Europe map.png|thumb|Map of Europe during the Toarcian Age]]
During the Jurassic, the North [[Atlantic Ocean]] remained relatively narrow, while the South Atlantic did not open until the Cretaceous.<ref>{{Cite journal|last1=Hosseinpour|first1=Maral|last2=Williams|first2=Simon|last3=Seton|first3=Maria|last4=Barnett-Moore|first4=Nicholas|last5=Müller|first5=R. Dietmar|date=2016-10-02|title=Tectonic evolution of Western Tethys from Jurassic to present day: coupling geological and geophysical data with seismic tomography models|url=https://www.tandfonline.com/doi/full/10.1080/00206814.2016.1183146|journal=[[International Geology Review]]|language=en|volume=58|issue=13|pages=1616–1645|doi=10.1080/00206814.2016.1183146|bibcode=2016IGRv...58.1616H|hdl=2123/20835|s2cid=130537970|issn=0020-6814|hdl-access=free}}</ref><ref name="Frizon de Lamotte-2015" /> The continents were surrounded by [[Panthalassa]], with the [[Tethys Ocean]] between Gondwana and Asia. At the end of the Triassic, there was a [[marine transgression]] in Europe, flooding most parts of central and western Europe transforming it into an archipelago of islands surrounded by shallow seas.<ref>{{Cite journal|last1=Barth|first1=G.|last2=Franz|first2=M.|last3=Heunisch|first3=C.|last4=Ernst|first4=W.|last5=Zimmermann|first5=J.|last6=Wolfgramm|first6=M.|date=2018-01-01|title=Marine and terrestrial sedimentation across the T–J transition in the North German Basin|url=http://www.sciencedirect.com/science/article/pii/S0031018217303140|journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]]|language=en|volume=489|pages=74–94|doi=10.1016/j.palaeo.2017.09.029|bibcode=2018PPP...489...74B|issn=0031-0182|url-access=subscription}}</ref> During the Jurassic, both the North and South Pole were covered by oceans.<ref name="Scotese-2021" /> Beginning in the Early Jurassic, the Boreal Ocean was connected to the proto-Atlantic by the "Viking corridor" or Transcontinental Laurasian Seaway, a passage between the [[Baltic Shield]] and [[Greenland]] several hundred kilometers wide.<ref name="Korte-2015">{{Cite journal|last1=Korte|first1=Christoph|last2=Hesselbo|first2=Stephen P.|last3=Ullmann|first3=Clemens V.|last4=Dietl|first4=Gerd|last5=Ruhl|first5=Micha|last6=Schweigert|first6=Günter|last7=Thibault|first7=Nicolas|date=December 2015|title=Jurassic climate mode governed by ocean gateway|url= |journal=[[Nature Communications]]|language=en|volume=6|issue=1|article-number=10015|doi=10.1038/ncomms10015|issn=2041-1723|pmc=4682040|pmid=26658694|bibcode=2015NatCo...610015K}}</ref><ref>{{Cite journal|last1=Bjerrum|first1=Christian J.|last2=Surlyk|first2=Finn|last3=Callomon|first3=John H.|last4=Slingerland|first4=Rudy L.|date=August 2001|title=Numerical paleoceanographic study of the Early Jurassic Transcontinental Laurasian Seaway|url=http://doi.wiley.com/10.1029/2000PA000512|journal=[[Paleoceanography and Paleoclimatology]]|language=en|volume=16|issue=4|pages=390–404|doi=10.1029/2000PA000512|bibcode=2001PalOc..16..390B|s2cid=128465643 }}</ref><ref>{{cite journal |last1=Mitchell |first1=Andrew J. |last2=Allison |first2=Peter A. |last3=Gorman |first3=Gerald J. |last4=Piggott |first4=Matthew D. |last5=Pain |first5=Christopher C. |date=1 March 2011 |title=Tidal circulation in an ancient epicontinental sea: The Early Jurassic Laurasian Seaway |url=https://pubs.geoscienceworld.org/gsa/geology/article-abstract/39/3/207/130484/Tidal-circulation-in-an-ancient-epicontinental-sea?redirectedFrom=fulltext |journal=[[Geology (journal)|Geology]] |volume=39 |issue=3 |pages=207–210 |doi=10.1130/G31496.1 |bibcode=2011Geo....39..207M |access-date=21 April 2023|url-access=subscription }}</ref> During the Callovian, the [[Turgai Strait|Turgai Epicontinental Sea]] formed, creating a marine barrier between Europe and Asia.<ref>{{cite journal |last1=Upchurch |first1=Paul |last2=Hunn |first2=Craig A. |last3=Norman |first3=David B. |date=22 March 2002 |title=An analysis of dinosaurian biogeography: evidence for the existence of vicariance and dispersal patterns caused by geological events |journal=[[Proceedings of the Royal Society B: Biological Sciences]] |volume=269 |issue=1491 |pages=613–621 |doi=10.1098/rspb.2001.1921 |pmid=11916478 |pmc=1690931 }}</ref>
[[File:Mollweide Paleographic Map of Earth, 155 Ma (Oxfordian Age).png|thumb|Map of global geography during the Late Jurassic, around 155 million years ago|270x270px]]
Madagascar and Antarctica began to rift away from Africa during the late Early Jurassic in association with the eruption of the [[Karoo-Ferrar|Karoo-Ferrar large igneous provinces]], opening the western [[Indian Ocean]] and beginning the fragmentation of Gondwana.<ref>{{Cite journal|last1=Geiger|first1=Markus|last2=Clark|first2=David Norman|last3=Mette|first3=Wolfgang|date=March 2004|title=Reappraisal of the timing of the breakup of Gondwana based on sedimentological and seismic evidence from the Morondava Basin, Madagascar|url=https://linkinghub.elsevier.com/retrieve/pii/S0899536204000302|journal=[[Journal of African Earth Sciences]]|language=en|volume=38|issue=4|pages=363–381|doi=10.1016/j.jafrearsci.2004.02.003|bibcode=2004JAfES..38..363G|url-access=subscription}}</ref><ref>{{Cite journal|last1=Nguyen|first1=Luan C.|last2=Hall|first2=Stuart A.|last3=Bird|first3=Dale E.|last4=Ball|first4=Philip J.|date=June 2016|title=Reconstruction of the East Africa and Antarctica continental margins: AFRICA-ANTARCTICA RECONSTRUCTION|journal=Journal of Geophysical Research: Solid Earth|language=en|volume=121|issue=6|pages=4156–4179|doi=10.1002/2015JB012776|doi-access=free}}</ref> At the beginning of the Jurassic, North and South America remained connected, but by the beginning of the Late Jurassic they had rifted apart to form the Caribbean Seaway, also known as the Hispanic Corridor, which connected the North Atlantic Ocean with eastern Panthalassa. Palaeontological data suggest that the seaway had been open since the Early Jurassic.<ref>{{Cite book|last=Iturralde-Vinent|first=Manuel A.|date=2003-01-01|chapter=The Conflicting Paleontologic versus Stratigraphic Record of the Formation of the Caribbean Seaway|chapter-url=https://pubs.geoscienceworld.org/books/book/1286/chapter/107130406/The-Conflicting-Paleontologic-versus-Stratigraphic|title=The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon Habitats, Basin Formation and Plate Tectonics|language=en|publisher=[[American Association of Petroleum Geologists]]|volume=79|pages=|doi=10.1306/M79877|isbn=978-1-62981-054-6|via=}}</ref>

As part of the [[Nevadan orogeny]], which began during the Triassic, the [[Cache Creek Ocean]] closed, and various [[terrane]]s including the large [[Wrangellia Terrane]] [[Accretion (geology)|accreted]] onto the western margin of North America.<ref>{{Citation|last1=Blakey|first1=Ronald C.|title=The Arrival of Wrangellia and the Nevadan Orogeny: Late Triassic to Late Jurassic: Ca. 240–145 Ma|date=2018|url=http://link.springer.com/10.1007/978-3-319-59636-5_7|work=Ancient Landscapes of Western North America|pages=89–101|place=Cham|publisher=Springer International Publishing|language=en|doi=10.1007/978-3-319-59636-5_7|isbn=978-3-319-59634-1|access-date=2021-04-10|last2=Ranney|first2=Wayne D.|url-access=subscription}}</ref><ref>{{Cite journal|last1=Clennett|first1=Edward J.|last2=Sigloch|first2=Karin|last3=Mihalynuk|first3=Mitchell G.|last4=Seton|first4=Maria|last5=Henderson|first5=Martha A.|last6=Hosseini|first6=Kasra|last7=Mohammadzaheri|first7=Afsaneh|last8=Johnston|first8=Stephen T.|last9=Müller|first9=R. Dietmar|date=August 2020|title=A Quantitative Tomotectonic Plate Reconstruction of Western North America and the Eastern Pacific Basin|url=https://onlinelibrary.wiley.com/doi/10.1029/2020GC009117|journal=[[Geochemistry, Geophysics, Geosystems]]|language=en|volume=21|issue=8|article-number=e09117|bibcode=2020GGG....2109117C|doi=10.1029/2020GC009117|s2cid=225443040|issn=1525-2027}}</ref> By the Middle Jurassic the [[Siberia (continent)|Siberian plate]] and the North China-Amuria block had collided, resulting in the closure of the [[Mongol-Okhotsk Ocean]].<ref>{{Cite journal|last1=Yi|first1=Zhiyu|last2=Meert|first2=Joseph G.|date=2020-08-16|title=A Closure of the Mongol-Okhotsk Ocean by the Middle Jurassic: Reconciliation of Paleomagnetic and Geological Evidence|url=https://onlinelibrary.wiley.com/doi/10.1029/2020GL088235|journal=[[Geophysical Research Letters]]|language=en|volume=47|issue=15|article-number=e2020GL088235 |doi=10.1029/2020GL088235|bibcode=2020GeoRL..4788235Y|s2cid=225430978|issn=0094-8276|url-access=subscription}}</ref>
[[File:Pacific Ocean 180Ma.jpg|thumb|Formation of the Pacific Plate during the Early Jurassic]]

During the Early Jurassic, around 190 million years ago, the [[Pacific Plate]] originated at the [[triple junction]] of the [[Farallon Plate|Farallon]], [[Phoenix Plate|Phoenix]], and [[Izanagi Plate|Izanagi]] [[Plate tectonics|tectonic plates]], the three main [[Oceanic crust|oceanic plates]] of Panthalassa. The previously stable triple junction had converted to an unstable arrangement surrounded on all sides by [[transform fault]]s because of a kink in one of the plate boundaries, resulting in the formation of the Pacific Plate at the centre of the junction.<ref>{{Cite journal|last1=Boschman|first1=Lydian M.|last2=van Hinsbergen|first2=Douwe J. J.|date=July 2016|title=On the enigmatic birth of the Pacific Plate within the Panthalassa Ocean|url= |journal=[[Science Advances]]|language=en|volume=2|issue=7|article-number=e1600022|doi=10.1126/sciadv.1600022|issn=2375-2548|pmc=5919776|pmid=29713683|bibcode=2016SciA....2E0022B}}</ref> During the Middle to early Late Jurassic, the [[Sundance Sea]]way, a shallow [[Inland sea (geology)|epicontinental sea]], covered much of northwest North America.<ref>{{Cite journal|last1=Danise|first1=Silvia|last2=Holland|first2=Steven M.|date=July 2018|title=A Sequence Stratigraphic Framework for the Middle to Late Jurassic of the Sundance Seaway, Wyoming: Implications for Correlation, Basin Evolution, and Climate Change|url=https://www.journals.uchicago.edu/doi/10.1086/697692|journal=[[The Journal of Geology]]|language=en|volume=126|issue=4|pages=371–405|doi=10.1086/697692|bibcode=2018JG....126..371D|s2cid=133707199|issn=0022-1376|url-access=subscription}}</ref>[[File:OoidSurface01.jpg|thumb|Grainstone with calcitic [[ooids]] and sparry calcite cement; [[Carmel Formation]], Middle Jurassic, of southern Utah, US]]The [[eustatic sea level]] is estimated to have been close to present levels during the Hettangian and Sinemurian, rising several tens of metres during the late Sinemurian–Pliensbachian before regressing to near present levels by the late Pliensbachian. There seems to have been a gradual rise to a peak of ~75 m above present sea level during the Toarcian. During the latest part of the Toarcian, the sea level again dropped by several tens of metres. It progressively rose from the Aalenian onwards, aside from dips of a few tens of metres in the Bajocian and around the Callovian–Oxfordian boundary, peaking possibly as high as 140 metres above present sea level at the Kimmeridgian–Tithonian boundary. The sea levels falls in the late Tithonian, perhaps to around 100 metres, before rebounding to around 110 metres at the Tithonian–Berriasian boundary.

The sea level within the long-term trends across the Jurassic was cyclical, with 64 fluctuations, 15 of which were over 75 metres. The most noted [[Stratigraphic cycles|cyclicity]] in Jurassic rocks is fourth order, with a periodicity of approximately 410,000 years.<ref>{{Cite journal|last=Haq|first=Bilal U.|date=2018-01-01|title=Jurassic Sea-Level Variations: A Reappraisal|url=https://www.geosociety.org/gsatoday/science/G359A/abstract.htm|journal=GSA Today|pages=4–10|doi=10.1130/GSATG359A.1|doi-access=free}}</ref>

During the Early Jurassic the world's oceans transitioned from an [[aragonite sea]] to a [[calcite sea]] chemistry, favouring the dissolution of [[aragonite]] and precipitation of [[calcite]].<ref>{{Cite journal|last1=Vulpius|first1=Sara|last2=Kiessling|first2=Wolfgang|date=January 2018|title=New constraints on the last aragonite–calcite sea transition from early Jurassic ooids|url=http://link.springer.com/10.1007/s10347-017-0516-x|journal=Facies|language=en|volume=64|issue=1|page=3|doi=10.1007/s10347-017-0516-x|bibcode=2018Faci...64....3V |s2cid=135202813|issn=0172-9179|url-access=subscription}}</ref> The rise of calcareous [[plankton]] during the Middle Jurassic profoundly altered ocean chemistry, with the deposition of [[Biomineralization|biomineralized]] plankton on the ocean floor acting as a [[Buffer solution|buffer]] against large CO<sub>2</sub> emissions.<ref>{{Cite journal|last1=Eichenseer|first1=Kilian|last2=Balthasar|first2=Uwe|last3=Smart|first3=Christopher W.|last4=Stander|first4=Julian|last5=Haaga|first5=Kristian A.|last6=Kiessling|first6=Wolfgang|date=August 2019|title=Jurassic shift from abiotic to biotic control on marine ecological success|url=http://www.nature.com/articles/s41561-019-0392-9|journal=[[Nature Geoscience]]|language=en|volume=12|issue=8|pages=638–642|doi=10.1038/s41561-019-0392-9|bibcode=2019NatGe..12..638E |hdl=10026.1/14472|s2cid=197402218|issn=1752-0894|hdl-access=free}}</ref>

== Climate ==
The climate of the Jurassic was generally warmer than that of present, by around {{convert|5|-|10|C-change|0}}, with [[Carbon dioxide in Earth's atmosphere|atmospheric carbon dioxide]] likely about four times higher. Intermittent "cold snap" intervals are known to have occurred during this time period, however, interrupting the otherwise warm greenhouse climate.<ref>{{cite journal |last1=Dai |first1=Xianduo |last2=Du |first2=Yuansheng |last3=Ziegler |first3=Martin |last4=Wang |first4=Chaowen |last5=Ma |first5=Qianli |last6=Chai |first6=Rong |last7=Guo |first7=Hua |date=1 January 2022 |title=Middle Triassic to Late Jurassic climate change on the northern margin of the South China Plate: Insights from chemical weathering indices and clay mineralogy |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018221005290 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=585 |article-number=110744 |doi=10.1016/j.palaeo.2021.110744 |bibcode=2022PPP...58510744D |hdl=1874/419504 |s2cid=243463781 |access-date=9 January 2023|hdl-access=free }}</ref> Forests likely grew near the poles, where they experienced warm summers and cold, sometimes snowy winters; there were unlikely to have been ice sheets given the high summer temperatures that prevented the accumulation of snow, though there may have been mountain glaciers.<ref name="Sellwood-2008" /> [[Dropstone]]s and [[glendonite]]s in northeastern [[Siberia]] during the Early to Middle Jurassic indicate cold winters.<ref name="Scotese-2021-2">{{Cite journal|last1=Scotese|first1=Christopher R.|last2=Song|first2=Haijun|last3=Mills|first3=Benjamin J.W.|last4=van der Meer|first4=Douwe G.|date=April 2021|title=Phanerozoic paleotemperatures: The earth's changing climate during the last 540 million years|journal=[[Earth-Science Reviews]]|volume=215|article-number=103503|bibcode=2021ESRv..21503503S|doi=10.1016/j.earscirev.2021.103503|issn=0012-8252|s2cid=233579194}} [https://eprints.whiterose.ac.uk/169823/ Alt URL]</ref> The ocean depths were likely {{convert|8|C-change}} warmer than present, and [[coral reef]]s grew 10° of latitude further north and south. The [[Intertropical Convergence Zone]] likely existed over the oceans, resulting in large areas of desert and scrubland in the lower latitudes between 40° N and S of the equator. [[Tropical rainforest]] and [[tundra]] biomes are likely to have been rare or absent.<ref name="Sellwood-2008">{{Cite journal|last1=Sellwood|first1=Bruce W.|last2=Valdes|first2=Paul J.|date=2008|title=Jurassic climates|url=https://linkinghub.elsevier.com/retrieve/pii/S0016787859800687|journal=Proceedings of the Geologists' Association|language=en|volume=119|issue=1|pages=5–17|doi=10.1016/S0016-7878(59)80068-7|bibcode=2008PrGA..119....5S |via=|url-access=subscription}}</ref> The Jurassic also witnessed the decline of the Pangaean megamonsoon that had characterised the preceding Permian and Triassic periods.<ref>{{cite journal |last1=Landwehrs |first1=Jan |last2=Feulner |first2=Georg |last3=Petri |first3=Stefan |last4=Sames |first4=Benjamin |last5=Wagreich |first5=Michael |date=20 May 2021 |title=Investigating Mesozoic Climate Trends and Sensitivities With a Large Ensemble of Climate Model Simulations |journal=[[Paleoceanography and Paleoclimatology]] |volume=36 |issue=6 |article-number=e2020PA004134 |doi=10.1029/2020PA004134 |pmid=34240008 |pmc=8251552 |bibcode=2021PaPa...36.4134L }}</ref> Variation in the frequency of [[wildfire]] activity in the Jurassic was governed by the 405 kyr [[Orbital eccentricity|eccentricity]] cycle.<ref>{{Cite journal |last1=Zhang |first1=Zhihui |last2=Lv |first2=Dawei |last3=Lu |first3=Man |last4=Yu |first4=Zicheng |last5=Gao |first5=Yuan |last6=Wang |first6=Tiantian |last7=Gao |first7=Jie |last8=Wang |first8=Chengshan |date=March 2023 |title=Wildfire activity driven by the 405-kyr orbital climate cycles in the Middle Jurassic |url=https://www.sciencedirect.com/science/article/abs/pii/S0921818123000425 |journal=[[Global and Planetary Change]] |language=en |volume=222 |article-number=104069 |doi=10.1016/j.gloplacha.2023.104069 |bibcode=2023GPC...22204069Z |s2cid=257059454 |access-date=16 September 2023|url-access=subscription }}</ref> Thanks to the breakup of Pangaea, the hydrological cycle during the Jurassic was significantly enhanced.<ref>{{Cite journal |last1=Allmon |first1=Warren D. |last2=Martin |first2=Ronald E. |date=Spring 2014 |title=Seafood through time revisited: the Phanerozoic increase in marine trophic resources and its macroevolutionary consequences |url=https://www.cambridge.org/core/journals/paleobiology/article/abs/seafood-through-time-revisited-the-phanerozoic-increase-in-marine-trophic-resources-and-its-macroevolutionary-consequences/1753FC13BED81B60E9BDDC0C3B9A682A |journal=[[Paleobiology (journal)|Paleobiology]] |language=en |volume=40 |issue=2 |pages=256–287 |doi=10.1666/13065 |s2cid=86765146 |issn=0094-8373 |access-date=16 September 2023|url-access=subscription }}</ref>

The beginning of the Jurassic was likely marked by a thermal spike corresponding to the Triassic–Jurassic extinction and eruption of the Central Atlantic magmatic province. The first part of the Jurassic was marked by the Early Jurassic Cool Interval between 199 and 183 million years ago.<ref name="Scotese-2021-2" /> It has been proposed that glaciation was present in the Northern Hemisphere during both the early Pliensbachian<ref>{{cite journal |last1=Bougeault |first1=Cédric |last2=Pellenard |first2=Pierre |last3=Deconinck |first3=Jean-François |last4=Hesselbo |first4=Stephen P. |last5=Dommergues |first5=Jean-Louis |last6=Bruneau |first6=Ludovic |last7=Cocquerez |first7=Théophile |last8=Laffont |first8=Rémi |last9=Huret |first9=Emilia |last10=Thibault |first10=Nicholas |date=February 2017 |title=Climatic and palaeoceanographic changes during the Pliensbachian (Early Jurassic) inferred from clay mineralogy and stable isotope (C-O) geochemistry (NW Europe) |url=https://www.sciencedirect.com/science/article/abs/pii/S0921818116304271 |journal=[[Global and Planetary Change]] |volume=149 |pages=139–152 |doi=10.1016/j.gloplacha.2017.01.005 |bibcode=2017GPC...149..139B |hdl=10871/25335 |access-date=14 May 2023|hdl-access=free }}</ref> and the latest Pliensbachian.<ref>{{Cite journal|last1=Ruebsam|first1=Wolfgang|last2=Mayer |first2=Bernhard|last3=Schwark|first3=Lorenz |date=January 2019 |title=Cryosphere carbon dynamics control early Toarcian global warming and sea level evolution |journal=[[Global and Planetary Change]]|language=en|volume=172|pages=440–453 |doi=10.1016/j.gloplacha.2018.11.003|bibcode=2019GPC...172..440R |url=https://linkinghub.elsevier.com/retrieve/pii/S0921818118305009|s2cid=133660136|url-access=subscription}}</ref><ref>{{Cite journal|last1=Ruebsam|first1=Wolfgang |last2=Schwark|first2=Lorenz|date=2021-05-11|title=Impact of a northern-hemispherical cryosphere on late Pliensbachian–early Toarcian climate and environment evolution|url=http://sp.lyellcollection.org/lookup/doi/10.1144/SP514-2021-11|journal=Geological Society, London, Special Publications |volume=514|issue=1|language=en|pages=SP514–2021–11|doi=10.1144/SP514-2021-11|bibcode=2021GSLSP.514..359R|s2cid=236600012|issn=0305-8719|url-access=subscription}}</ref> There was a spike in global temperatures of around {{convert|4|-|8|C-change|0}} during the early part of the Toarcian corresponding to the Toarcian Oceanic Anoxic Event and the eruption of the Karoo-Ferrar [[large igneous province]]s in southern Gondwana, with the warm interval extending to the end of the Toarcian around 174 million years ago.<ref name="Scotese-2021-2" /> During the Toarcian Warm Interval, ocean surface temperatures likely exceeded {{convert|30|°C|°F}}, and equatorial and subtropical (30°N–30°S) regions are likely to have been extremely arid, with temperatures in the interior of Pangea likely in excess of {{convert|40|°C|°F}}.The Toarcian Warm Interval is followed by the Middle Jurassic Cool Interval (MJCI) between 174 and 164 Ma,<ref name="Scotese-2021-2" /> which may have been punctuated by brief, ephemeral icehouse intervals.<ref>{{cite journal |last1=Ikeda |first1=Masayuki |last2=Bôle |first2=Maximilien |last3=Baumgartner |first3=Peter O. |date=1 September 2016 |title=Orbital-scale changes in redox condition and biogenic silica/detrital fluxes of the Middle Jurassic Radiolarite in Tethys (Sogno, Lombardy, N-Italy): Possible link with glaciation? |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018216302012 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=457 |pages=247–257 |doi=10.1016/j.palaeo.2016.06.009 |bibcode=2016PPP...457..247I |access-date=10 April 2023|url-access=subscription }}</ref><ref>{{cite journal |last1=Li |first1=Jun |last2=Huang |first2=Cheng-Min |last3=Yang |first3=Guo-Lin |last4=Pan |first4=Yuan-Yuan |last5=Wen |first5=Xing-Yue |date=January 2022 |title=Middle Jurassic climate oscillations from paleosol records of the Sichuan Basin, SW China |journal=Journal of Palaeogeography |volume=11 |issue=1 |pages=97–122 |doi=10.1016/j.jop.2022.01.003 |bibcode=2022JPalG..11...97L |s2cid=252949484 |doi-access=free }}</ref> During the Aalenian, precessionally forced climatic changes dictated peatland wildfire magnitude and frequency.<ref>{{Cite journal |last1=Zhang |first1=Zhihui |last2=Wang |first2=Chengshan |last3=Lv |first3=Dawei |last4=Hay |first4=William W. |last5=Wang |first5=Tiantian |last6=Cao |first6=Shuo |date=1 January 2020 |title=Precession-scale climate forcing of peatland wildfires during the early middle Jurassic greenhouse period |url=https://www.sciencedirect.com/science/article/pii/S0921818119305363 |journal=[[Global and Planetary Change]] |volume=184 |article-number=103051 |doi=10.1016/j.gloplacha.2019.103051 |bibcode=2020GPC...18403051Z |issn=0921-8181 |access-date=26 February 2024 |via=Elsevier Science Direct|url-access=subscription }}</ref> The European climate appears to have become noticeably more humid at the Aalenian-Bajocian boundary but then became more arid during the middle Bajocian.<ref>{{Cite journal |last1=Hesselbo |first1=Stephen P. |last2=Morgans-Bell |first2=Helen S. |last3=McElwain |first3=Jennifer C. |last4=Rees |first4=P. McAllister |last5=Robinson |first5=Stuart A. |last6=Ross |first6=C. Elizabeth |date=May 2003 |title=Carbon-Cycle Perturbation in the Middle Jurassic and Accompanying Changes in the Terrestrial Paleoenvironment |url=https://www.journals.uchicago.edu/doi/10.1086/373968 |journal=[[The Journal of Geology]] |language=en |volume=111 |issue=3 |pages=259–276 |doi=10.1086/373968 |bibcode=2003JG....111..259H |issn=0022-1376 |access-date=4 May 2024 |via=The University of Chicago Press Journals|url-access=subscription }}</ref> A transient ice age possibly occurred in the late Bajocian.<ref>{{cite journal |last1=Wierzbowski |first1=H. |last2=Joachimski |first2=M. |date=22 October 2007 |title=Reconstruction of late Bajocian–Bathonian marine palaeoenvironments using carbon and oxygen isotope ratios of calcareous fossils from the Polish Jura Chain (central Poland) |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018207003926 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=254 |issue=3–4 |pages=523–540 |doi=10.1016/j.palaeo.2007.07.010 |bibcode=2007PPP...254..523W |access-date=10 April 2023|url-access=subscription }}</ref> The Callovian-Oxfordian boundary at the end of the MJCI witnessed particularly notable global cooling,<ref name="JenkynsEtAl2012ClimateOfThePast">{{cite journal |last1=Jenkyns |first1=Hugh C. |last2=Schouten-Huibers |first2=L. |last3=Schouten |first3=S. |last4=Sinninghe Damsté |first4=Jaap S. |date=2 February 2012 |title=Warm Middle Jurassic–Early Cretaceous high-latitude sea-surface temperatures from the Southern Ocean |url=https://cp.copernicus.org/articles/8/215/2012/cp-8-215-2012.html |journal=[[Climate of the Past]] |volume=8 |issue=1 |pages=215–226 |doi=10.5194/cp-8-215-2012 |bibcode=2012CliPa...8..215J |s2cid=203095372 |access-date=8 April 2023 |doi-access=free }}</ref><ref name="Li2022" /> potentially even an ice age.<ref>{{cite journal |last1=Dromart |first1=G. |last2=Garcia |first2=J.-P. |last3=Picard |first3=S. |last4=Atrops |first4=F. |last5=Lécuyer |first5=C. |last6=Sheppard |first6=S. M. F. |date=25 August 2003 |title=Ice age at the Middle–Late Jurassic transition? |url=https://www.sciencedirect.com/science/article/abs/pii/S0012821X03002875 |journal=[[Earth and Planetary Science Letters]] |volume=213 |issue=3–4 |pages=205–220 |doi=10.1016/S0012-821X(03)00287-5 |bibcode=2003E&PSL.213..205D |access-date=8 January 2023|url-access=subscription }}</ref> This is followed by the Kimmeridgian Warm Interval (KWI) between 164 and 150 Ma.<ref name="Scotese-2021-2" /> Based on fossil [[wood]] distribution, this was one of the wettest intervals of the Jurassic.<ref>{{cite journal |last1=Philippe |first1=Marc |last2=Puijalon |first2=Sara |last3=Suan |first3=Guillaume |last4=Mousset |first4=Sylvain |last5=Thévenard |first5=Frédéric |last6=Mattioli |first6=Emanuela |date=15 January 2017 |title=The palaeolatitudinal distribution of fossil wood genera as a proxy for European Jurassic terrestrial climate |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018216304096 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=466 |pages=373–381 |doi=10.1016/j.palaeo.2016.11.029 |bibcode=2017PPP...466..373P |access-date=10 June 2023|url-access=subscription }}</ref> The Pangaean interior had less severe seasonal swings than in previous warm periods as the expansion of the Central Atlantic and Western Indian Ocean provided new sources of moisture.<ref name="Scotese-2021-2" /> A prominent drop in temperatures occurred during the Tithonian, known as the Early Tithonian Cooling Event (ETCE).<ref name="Li2022">{{cite journal |last1=Li |first1=Gaojie |last2=Xia |first2=Guoqing |last3=Yi |first3=Haisheng |last4=Wu |first4=Chihua |last5=Wagreich |first5=Michael |date=15 September 2022 |title=Climate changes as recorded in stable carbon isotopic compositions of the Late Jurassic marine sedimentary succession in the Qiangtang Basin, Northern Tibet |url=https://www.sciencedirect.com/science/article/abs/pii/S1367912022002486 |journal=[[Journal of Asian Earth Sciences]] |volume=236 |article-number=105317 |doi=10.1016/j.jseaes.2022.105317 |bibcode=2022JAESc.23605317L |s2cid=250103419 |access-date=8 January 2023|url-access=subscription }}</ref> The end of the Jurassic was marked by the Tithonian–early Barremian Cool Interval (TBCI), beginning 150 Ma and continuing into the [[Early Cretaceous]].<ref name="Scotese-2021-2" />

=== Climatic events ===
==== Toarcian Oceanic Anoxic Event ====
{{Main|Toarcian Oceanic Anoxic Event}}
The Toarcian Oceanic Anoxic Event (TOAE), also known as the Jenkyns Event, was an episode of widespread [[Anoxic event|oceanic anoxia]] during the early part of the Toarcian Age, c. 183 Ma. It is marked by a globally documented high amplitude negative [[Carbon isotope ratio|carbon isotope]] excursion,<ref>{{Cite journal|last1=Them|first1=T.R.|last2=Gill|first2=B.C.|last3=Caruthers|first3=A.H.|last4=Gröcke|first4=D.R.|last5=Tulsky|first5=E.T.|last6=Martindale|first6=R.C.|last7=Poulton|first7=T.P.|last8=Smith|first8=P.L.|date=February 2017|title=High-resolution carbon isotope records of the Toarcian Oceanic Anoxic Event (Early Jurassic) from North America and implications for the global drivers of the Toarcian carbon cycle|journal=[[Earth and Planetary Science Letters]]|language=en|volume=459|pages=118–126|doi=10.1016/j.epsl.2016.11.021|bibcode=2017E&PSL.459..118T|doi-access=free}}</ref><ref>{{cite journal |last1=Ros-Franch |first1=Sonia |last2=Echevarría |first2=Javier |last3=Damborenea |first3=Susana E. |last4=Manceñido |first4=Miguel O. |last5=Jenkyns |first5=Hugh C. |last6=Al-Suwaidi |first6=Aisha |last7=Hesselbo |first7=Stephen P. |last8=Riccardi |first8=Alberto C. |date=1 July 2019 |title=Population response during an Oceanic Anoxic Event: The case of Posidonotis (Bivalvia) from the Lower Jurassic of the Neuquén Basin, Argentina |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018219301415 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=525 |pages=57–67 |doi=10.1016/j.palaeo.2019.04.009 |bibcode=2019PPP...525...57R |hdl=11336/128130 |s2cid=146525666 |access-date=23 November 2022|hdl-access=free }}</ref> as well as the deposition of black [[shale]]s<ref name="WignallAndBond2008">{{cite journal |last1=Wignall |first1=Paul B. |last2=Bond |first2=David P. G. |date=2008 |title=The end-Triassic and Early Jurassic mass extinction records in the British Isles |url=https://www.sciencedirect.com/science/article/abs/pii/S0016787808802593 |journal=[[Proceedings of the Geologists' Association]] |volume=119 |issue=1 |pages=73–84 |doi=10.1016/S0016-7878(08)80259-3 |bibcode=2008PrGA..119...73W |access-date=23 November 2022|url-access=subscription }}</ref> and the extinction and collapse of carbonate-producing marine organisms, associated with a major rise in global temperatures.<ref name="Reolid-2021">{{Cite journal|last1=Reolid|first1=Matías|last2=Mattioli|first2=Emanuela|last3=Duarte|first3=Luís V.|last4=Ruebsam|first4=Wolfgang|date=2021-09-22|title=The Toarcian Oceanic Anoxic Event: where do we stand?|url=https://sp.lyellcollection.org/content/early/2021/09/21/SP514-2021-74|journal=Geological Society, London, Special Publications|language=en|volume=514|issue=1|pages=1–11|doi=10.1144/SP514-2021-74|bibcode=2021GSLSP.514....1R|s2cid=238683028|issn=0305-8719|url-access=subscription}}</ref>

The TOAE is often attributed to the eruption of the Karoo-Ferrar large igneous provinces and the associated increase of carbon dioxide concentration in the atmosphere, as well as the possible associated release of [[methane clathrate]]s.<ref name="Reolid-2021" /> This likely accelerated the [[hydrological cycle]] and increased [[Carbonate–silicate cycle|silicate weathering]], as evidenced by an increased amount of organic matter of terrestrial origin found in marine deposits during the TOAE.<ref>{{cite journal |last1=Rodrigues |first1=Bruno |last2=Duarte |first2=Luís V. |last3=Silva |first3=Ricardo L. |last4=Mendonça Filho |first4=João Graciano |date=15 September 2020 |title=Sedimentary organic matter and early Toarcian environmental changes in the Lusitanian Basin (Portugal) |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018220302261 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=554 |article-number=109781 |doi=10.1016/j.palaeo.2020.109781 |bibcode=2020PPP...55409781R |s2cid=219059687 |access-date=27 September 2022|url-access=subscription }}</ref> Groups affected include ammonites,<ref>{{Cite journal |last1=Dera |first1=Guillaume |last2=Neige |first2=Pascal |last3=Dommergues |first3=Jean-Louis |last4=Fara |first4=Emmanuel |last5=Laffont |first5=Rémi |last6=Pellenard |first6=Pierre |date=January 2010 |title=High-resolution dynamics of Early Jurassic marine extinctions: the case of Pliensbachian–Toarcian ammonites (Cephalopoda) |url=http://jgs.lyellcollection.org/lookup/doi/10.1144/0016-76492009-068 |journal=[[Journal of the Geological Society]] |language=en |volume=167 |issue=1 |pages=21–33 |doi=10.1144/0016-76492009-068 |bibcode=2010JGSoc.167...21D |s2cid=128908746 |issn=0016-7649|url-access=subscription }}</ref> [[ostracod]]s,<ref name="WignallAndBond2008" /><ref>{{cite journal |last1=Arias |first1=Carmen |date=1 October 2013 |title=The early Toarcian (early Jurassic) ostracod extinction events in the Iberian Range: The effect of temperature changes and prolonged exposure to low dissolved oxygen concentrations |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018213003258 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=387 |pages=40–55 |doi=10.1016/j.palaeo.2013.07.004 |bibcode=2013PPP...387...40A |access-date=23 November 2022}}</ref> [[foraminifera]],<ref>{{cite journal |last1=Hess |first1=Silvia |last2=Nagy |first2=Jenő |last3=Laursen |first3=Gitte Vestergaard |date=28 January 2014 |title=Benthic foraminifera from the Lower Jurassic transgressive mudstones of the south-western Barents Sea—a possible high-latitude expression of the global Pliensbachian–Toarcian turnover? |journal=[[Polar Research]] |volume=33 |issue=1 |article-number=20206 |doi=10.3402/polar.v33.20206 |s2cid=128492520 |doi-access=free }}</ref><ref>{{cite journal |last1=Reolid |first1=Matías |last2=Copestake |first2=Philip |last3=Johnson |first3=Ben |date=15 October 2019 |title=Foraminiferal assemblages, extinctions and appearances associated with the Early Toarcian Oceanic Anoxic Event in the Llanbedr (Mochras Farm) Borehole, Cardigan Bay Basin, United Kingdom |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018219303980 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=532 |article-number=109277 |doi=10.1016/j.palaeo.2019.109277 |bibcode=2019PPP...53209277R |s2cid=200072488 |access-date=23 November 2022|url-access=subscription }}</ref> [[Bivalvia|bivalves]],<ref name="WignallAndBond2008" /> [[cnidaria]]ns, and especially [[Brachiopoda|brachiopods]],<ref>{{cite journal |last1=Danise |first1=Silvia |last2=Clémence |first2=Marie-Emilie |last3=Price |first3=Gregory D. |last4=Murphy |first4=Daniel P. |last5=Gómez |first5=Juan J. |last6=Twitchett |first6=Richard J. |date=15 June 2019 |title=Stratigraphic and environmental control on marine benthic community change through the early Toarcian extinction event (Iberian Range, Spain) |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018218309258 |journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]] |volume=524 |pages=183–200 |doi=10.1016/j.palaeo.2019.03.039 |bibcode=2019PPP...524..183D |hdl=10026.1/13668 |s2cid=134835736 |access-date=23 November 2022|hdl-access=free }}</ref><ref>{{Cite journal|last1=Caruthers|first1=Andrew H.|last2=Smith|first2=Paul L.|last3=Gröcke|first3=Darren R.|date=September 2013|title=The Pliensbachian–Toarcian (Early Jurassic) extinction, a global multi-phased event|url=https://linkinghub.elsevier.com/retrieve/pii/S0031018213002344|journal=[[Palaeogeography, Palaeoclimatology, Palaeoecology]]|language=en|volume=386|pages=104–118|doi=10.1016/j.palaeo.2013.05.010|bibcode=2013PPP...386..104C|url-access=subscription}}</ref><ref name="VörösKocsisPálfy2016">{{cite journal |last1=Vörös |first1=Attila |last2=Kocsis |first2=Ádám |last3=Pálfy |first3=József |date=1 September 2016 |title=Demise of the last two spire-bearing brachiopod orders (Spiriferinida and Athyridida) at the Toarcian (Early Jurassic) extinction event |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018216302140#! |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=457 |pages=233–241 |doi=10.1016/j.palaeo.2016.06.022 |bibcode=2016PPP...457..233V |access-date=29 October 2022}}</ref> for which the TOAE represented one of the most severe extinctions in their evolutionary history.<ref name="JoranBaeza-CarrataláGoy2018">{{cite journal |last1=Joran |first1=Fernando García |last2=Baeza-Carratalá |first2=José Francisco |last3=Goy |first3=Antonio |date=1 October 2018 |title=Changes in brachiopod body size prior to the Early Toarcian (Jurassic) Mass Extinction |url=https://www.sciencedirect.com/science/article/abs/pii/S0031018218304644#! |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |volume=506 |pages=242–249 |doi=10.1016/j.palaeo.2018.06.045 |bibcode=2018PPP...506..242G |hdl=10045/77781 |s2cid=135368506 |access-date=29 October 2022|hdl-access=free }}</ref> While the event had significant impact on marine invertebrates, it had little effect on marine reptiles.<ref>{{Cite journal|last1=Maxwell|first1=Erin E.|last2=Vincent|first2=Peggy|date=2015-11-06|title=Effects of the early Toarcian Oceanic Anoxic Event on ichthyosaur body size and faunal composition in the Southwest German Basin|journal=Paleobiology|volume=42|issue=1|pages=117–126|doi=10.1017/pab.2015.34|s2cid=131623205|issn=0094-8373}}</ref> During the TOAE, the [[Sichuan Basin]] was transformed into a giant [[lake]], probably three times the size of modern-day [[Lake Superior]], represented by the Da'anzhai Member of the [[Ziliujing Formation]]. The lake likely [[Carbon sequestration|sequestered]] ~460 gigatons (Gt) of organic carbon and ~1,200 Gt of inorganic carbon during the event.<ref>{{Cite journal|last1=Xu|first1=Weimu|last2=Ruhl|first2=Micha|last3=Jenkyns|first3=Hugh C.|last4=Hesselbo|first4=Stephen P.|last5=Riding|first5=James B.|last6=Selby|first6=David|last7=Naafs|first7=B. David A.|last8=Weijers|first8=Johan W. H.|last9=Pancost|first9=Richard D.|last10=Tegelaar|first10=Erik W.|last11=Idiz|first11=Erdem F.|date=February 2017|title=Carbon sequestration in an expanded lake system during the Toarcian oceanic anoxic event|url=http://www.nature.com/articles/ngeo2871|journal=[[Nature Geoscience]]|language=en|volume=10|issue=2|pages=129–134|doi=10.1038/ngeo2871|bibcode=2017NatGe..10..129X|issn=1752-0894|hdl=10871/24965|hdl-access=free}}</ref> Seawater [[pH]], which had already substantially decreased prior to the event, increased slightly during the early stages of the TOAE, before dropping to its lowest point around the middle of the event.<ref>{{Cite journal|last1=Müller|first1=Tamás|last2=Jurikova|first2=Hana|last3=Gutjahr|first3=Marcus|last4=Tomašových|first4=Adam|last5=Schlögl|first5=Jan|last6=Liebetrau|first6=Volker|last7=Duarte|first7=Luís v.|last8=Milovský|first8=Rastislav|last9=Suan|first9=Guillaume|last10=Mattioli|first10=Emanuela|last11=Pittet|first11=Bernard|date=2020-12-01|title=Ocean acidification during the early Toarcian extinction event: Evidence from boron isotopes in brachiopods|journal=Geology|language=en|volume=48|issue=12|pages=1184–1188|doi=10.1130/G47781.1|bibcode=2020Geo....48.1184M|issn=0091-7613|doi-access=free|hdl=10023/20595|hdl-access=free}}</ref> This [[ocean acidification]] is the probable cause of the collapse of carbonate production.<ref>{{Cite journal|last1=Trecalli|first1=Alberto|last2=Spangenberg|first2=Jorge|last3=Adatte|first3=Thierry|last4=Föllmi|first4=Karl B.|last5=Parente|first5=Mariano|date=December 2012|title=Carbonate platform evidence of ocean acidification at the onset of the early Toarcian oceanic anoxic event|url=https://linkinghub.elsevier.com/retrieve/pii/S0012821X12005390|journal=Earth and Planetary Science Letters|language=en|volume=357–358|pages=214–225|doi=10.1016/j.epsl.2012.09.043|bibcode=2012E&PSL.357..214T|url-access=subscription}}</ref><ref>{{Cite journal|last1=Ettinger|first1=Nicholas P.|last2=Larson|first2=Toti E.|last3=Kerans|first3=Charles|last4=Thibodeau|first4=Alyson M.|last5=Hattori|first5=Kelly E.|last6=Kacur|first6=Sean M.|last7=Martindale|first7=Rowan C.|date=2020-09-23|editor-last=Eberli|editor-first=Gregor|title=Ocean acidification and photic-zone anoxia at the Toarcian Oceanic Anoxic Event: Insights from the Adriatic Carbonate Platform|url=https://onlinelibrary.wiley.com/doi/10.1111/sed.12786|journal=Sedimentology|volume=68|language=en|pages=63–107|doi=10.1111/sed.12786|s2cid=224870464|issn=0037-0746|url-access=subscription}}</ref> Additionally, anoxic conditions were exacerbated by enhanced recycling of [[phosphorus]] back into ocean water as a result of high ocean acidity and temperature inhibiting its mineralisation into apatite; the abundance of phosphorus in marine environments caused further eutrophication and consequent anoxia in a positive feedback loop.<ref>{{cite journal |last1=Papadomanolaki |first1=Nina M. |last2=Lenstra |first2=Wytze K. |last3=Wolthers |first3=Mariette |last4=Slomp |first4=Caroline P. |author-link4=Caroline Slomp|date=1 July 2022 |title=Enhanced phosphorus recycling during past oceanic anoxia amplified by low rates of apatite authigenesis |journal=[[Science Advances]] |volume=8 |issue=26 |article-number=eabn2370 |doi=10.1126/sciadv.abn2370 |pmid=35776794 |bibcode=2022SciA....8N2370P |hdl=1874/421467 |s2cid=250218660 |doi-access=free |pmc=10883373 |hdl-access=free }}</ref>

==== End-Jurassic transition ====
{{Main|Tithonian extinction event}}

The end-Jurassic transition was originally considered one of eight mass extinctions, but is now considered to be a complex interval of faunal turnover, with the increase in diversity of some groups and decline in others, though the evidence for this is primarily European, probably controlled by changes in eustatic sea level.<ref name="Tennant-2016">{{Cite journal|last1=Tennant|first1=Jonathan P.|last2=Mannion|first2=Philip D.|last3=Upchurch|first3=Paul|date=2016-09-02|title=Sea level regulated tetrapod diversity dynamics through the Jurassic/Cretaceous interval|url=|journal=[[Nature Communications]]|language=en|volume=7|issue=1|article-number=12737|bibcode=2016NatCo...712737T|doi=10.1038/ncomms12737|issn=2041-1723|pmc=5025807|pmid=27587285}}</ref>

== Flora ==
=== End-Triassic extinction ===
There is no evidence of a mass extinction of plants at the Triassic–Jurassic boundary.<ref name="Lucas-2015">{{Cite journal|last1=Lucas|first1=Spencer G.|last2=Tanner|first2=Lawrence H.|date=October 2015|title=End-Triassic nonmarine biotic events|journal=Journal of Palaeogeography|language=en|volume=4|issue=4|pages=331–348|doi=10.1016/j.jop.2015.08.010|bibcode=2015JPalG...4..331L|doi-access=free}}</ref> At the Triassic–Jurassic boundary in Greenland, the sporomorph (pollen and spores) record suggests a complete floral turnover.<ref>{{Cite journal|last1=Mander|first1=Luke|last2=Kürschner|first2=Wolfram M.|last3=McElwain|first3=Jennifer C.|date=2010-08-31|title=An explanation for conflicting records of Triassic–Jurassic plant diversity|journal=Proceedings of the National Academy of Sciences|language=en|volume=107|issue=35|pages=15351–15356|doi=10.1073/pnas.1004207107|issn=0027-8424|pmid=20713737|pmc=2932585|bibcode=2010PNAS..10715351M|doi-access=free}}</ref> An analysis of macrofossil floral communities in Europe suggests that changes were mainly due to local [[ecological succession]].<ref>{{Cite journal|last1=Barbacka|first1=Maria|last2=Pacyna|first2=Grzegorz|last3=Kocsis|first3=Ádam T.|last4=Jarzynka|first4=Agata|last5=Ziaja|first5=Jadwiga|last6=Bodor|first6=Emese|date=August 2017|title=Changes in terrestrial floras at the Triassic-Jurassic Boundary in Europe|url=https://linkinghub.elsevier.com/retrieve/pii/S0031018216304977|journal=Palaeogeography, Palaeoclimatology, Palaeoecology|language=en|volume=480|pages=80–93|doi=10.1016/j.palaeo.2017.05.024|bibcode=2017PPP...480...80B}}</ref> At the end of the Triassic, the [[Peltaspermaceae]] became extinct in most parts of the world, with ''[[Lepidopteris]]'' persisting into the Early Jurassic in Patagonia.<ref>{{Cite journal|last1=Elgorriaga|first1=Andrés|last2=Escapa|first2=Ignacio H.|last3=Cúneo|first3=N. Rubén|date=July 2019|title=Relictual Lepidopteris (Peltaspermales) from the Early Jurassic Cañadón Asfalto Formation, Patagonia, Argentina|url=https://www.journals.uchicago.edu/doi/10.1086/703461|journal=International Journal of Plant Sciences|language=en|volume=180|issue=6|pages=578–596|doi=10.1086/703461|bibcode=2019IJPlS.180..578E |issn=1058-5893|s2cid=195435840|url-access=subscription}}</ref> ''[[Dicroidium]]'', a [[Corystospermaceae|corystosperm]] seed fern that was a dominant part of Gondwanan floral communities during the Triassic, also declined at the Triassic–Jurassic boundary, surviving as a relict in Antarctica into the Early Jurassic.<ref>{{Citation|last1=Bomfleur|first1=Benjamin|title=Polar Regions of the Mesozoic–Paleogene Greenhouse World as Refugia for Relict Plant Groups|date=2018|url=https://linkinghub.elsevier.com/retrieve/pii/B9780128130124000243|work=Transformative Paleobotany|pages=593–611|publisher=Elsevier|language=en|doi=10.1016/b978-0-12-813012-4.00024-3|isbn=978-0-12-813012-4|access-date=2020-11-12|last2=Blomenkemper|first2=Patrick|last3=Kerp|first3=Hans|last4=McLoughlin|first4=Stephen}}</ref>

=== Floral composition ===
==== Conifers ====
[[File:Petrified Araucaria cone.jpg|thumb|Petrified ''[[Araucaria mirabilis]]'' cone from the Middle Jurassic of Argentina|alt=Two images of a round conifer cone, the left one is in cross-section]]
[[Conifer]]s formed a dominant component of Jurassic floras. The Late Triassic and Jurassic was a major time of diversification of conifers, with most modern conifer groups appearing in the fossil record by the end of the Jurassic, having evolved from [[Voltziales|voltzialean]] ancestors.<ref>{{Cite journal|last1=Atkinson|first1=Brian A.|last2=Serbet|first2=Rudolph|last3=Hieger|first3=Timothy J.|last4=Taylor|first4=Edith L.|date=October 2018|title=Additional evidence for the Mesozoic diversification of conifers: Pollen cone of Chimaerostrobus minutus gen. et sp. nov. (Coniferales), from the Lower Jurassic of Antarctica|journal=Review of Palaeobotany and Palynology|language=en|volume=257|pages=77–84|doi=10.1016/j.revpalbo.2018.06.013|bibcode=2018RPaPa.257...77A |s2cid=133732087|doi-access=free}}</ref><ref name="Leslie-2018">{{Cite journal|last1=Leslie|first1=Andrew B.|last2=Beaulieu|first2=Jeremy|last3=Holman|first3=Garth|last4=Campbell|first4=Christopher S.|last5=Mei|first5=Wenbin|last6=Raubeson|first6=Linda R.|last7=Mathews|first7=Sarah|date=September 2018|title=An overview of extant conifer evolution from the perspective of the fossil record|url=http://doi.wiley.com/10.1002/ajb2.1143|journal=American Journal of Botany|language=en|volume=105|issue=9|pages=1531–1544|doi=10.1002/ajb2.1143|pmid=30157290|s2cid=52120430 }}</ref>

[[Araucariaceae|Araucarian]] conifers have their first unambiguous records during the Early Jurassic, and members of the modern genus ''[[Araucaria]]'' were widespread across both hemispheres by the Middle Jurassic.<ref name="Leslie-2018" /><ref>{{Cite journal|last1=Stockey|first1=Ruth A.|last2=Rothwell|first2=Gar W.|date=July 2020|title=Diversification of crown group Araucaria: the role of Araucaria famii sp. nov. in the Late Cretaceous (Campanian) radiation of Araucariaceae in the Northern Hemisphere|journal=American Journal of Botany|language=en|volume=107|issue=7|pages=1072–1093|doi=10.1002/ajb2.1505|pmid=32705687|s2cid=225568264|issn=0002-9122|doi-access=free}}</ref><ref>{{Cite journal|last1=Escapa|first1=Ignacio H.|last2=Catalano|first2=Santiago A.|date=October 2013|title=Phylogenetic Analysis of Araucariaceae: Integrating Molecules, Morphology, and Fossils|url=https://www.journals.uchicago.edu/doi/10.1086/672369|journal=International Journal of Plant Sciences|language=en|volume=174|issue=8|pages=1153–1170|doi=10.1086/672369|bibcode=2013IJPlS.174.1153E |hdl=11336/3583|s2cid=56238574|issn=1058-5893|hdl-access=free}}</ref>

Also abundant during the Jurassic is the extinct family [[Cheirolepidiaceae]], often recognised through their highly distinctive ''Classopolis'' pollen. Jurassic representatives include the pollen cone ''Classostrobus'' and the seed cone ''[[Pararaucaria]]''. Araucarian and Cheirolepidiaceae conifers often occur in association.<ref>{{Cite journal|last1=Stockey|first1=Ruth A.|last2=Rothwell|first2=Gar W.|date=March 2013|title=Pararaucaria carrii sp. nov., Anatomically Preserved Evidence for the Conifer Family Cheirolepidiaceae in the Northern Hemisphere|url=https://www.journals.uchicago.edu/doi/10.1086/668614|journal=International Journal of Plant Sciences|language=en|volume=174|issue=3|pages=445–457|doi=10.1086/668614|bibcode=2013IJPlS.174..445S |s2cid=59269291|issn=1058-5893|url-access=subscription}}</ref>

The oldest definitive record of the cypress family ([[Cupressaceae]]) is ''[[Austrohamia|Austrohamia minuta]]'' from the Early Jurassic (Pliensbachian) of Patagonia, known from many parts of the plant.<ref>{{Cite journal|last1=Escapa|first1=Ignacio|last2=Cúneo|first2=Rubén|last3=Axsmith|first3=Brian|date=September 2008|title=A new genus of the Cupressaceae (sensu lato) from the Jurassic of Patagonia: Implications for conifer megasporangiate cone homologies|url=https://linkinghub.elsevier.com/retrieve/pii/S0034666708000481|journal=Review of Palaeobotany and Palynology|language=en|volume=151|issue=3–4|pages=110–122|doi=10.1016/j.revpalbo.2008.03.002|bibcode=2008RPaPa.151..110E |url-access=subscription}}</ref> The reproductive structures of ''Austrohamia'' have strong similarities to those of the primitive living cypress genera ''[[Taiwania]]'' and ''[[Cunninghamia]].'' By the Middle to Late Jurassic Cupressaceae were abundant in warm temperate–tropical regions of the Northern Hemisphere, most abundantly represented by the genus ''[[Elatides]]''.<ref>{{Cite journal|last1=Contreras|first1=Dori L.|last2=Escapa|first2=Ignacio H.|last3=Iribarren|first3=Rocio C.|last4=Cúneo|first4=N. Rubén|date=October 2019|title=Reconstructing the Early Evolution of the Cupressaceae: A Whole-Plant Description of a New Austrohamia Species from the Cañadón Asfalto Formation (Early Jurassic), Argentina|url=https://www.journals.uchicago.edu/doi/10.1086/704831|journal=International Journal of Plant Sciences|language=en|volume=180|issue=8|pages=834–868|doi=10.1086/704831|bibcode=2019IJPlS.180..834C |s2cid=202862782|issn=1058-5893|url-access=subscription}}</ref> The Jurassic also saw the first appearances of some modern genera of cypresses, such as ''[[Sequoia (genus)|Sequoia]]''.<ref name="Jehol">{{cite journal |last1=Ma |first1=Qing-Wen |last2=K. Ferguson |first2=David |last3=Liu |first3=Hai-Ming |last4=Xu |first4=Jing-Xian |date=2020 |title=Compressions of Sequoia (Cupressaceae sensu lato) from the Middle Jurassic of Daohugou, Ningcheng, Inner Mongolia, China |url=https://link.springer.com/article/10.1007/s12549-020-00454-z |journal=Palaeobiodiversity and Palaeoenvironments |volume=1 |issue=9 |page=1 |doi=10.1007/s12549-020-00454-z |s2cid=227180592 |access-date=9 March 2021 |ref=Jehol|url-access=subscription }}</ref>

Members of the extinct genus ''[[Schizolepidopsis]]'' which likely represent a [[stem-group]] to the pine family ([[Pinaceae]]), were widely distributed across Eurasia during the Jurassic.<ref>{{Cite journal|last1=Domogatskaya|first1=Ksenia V.|last2=Herman|first2=Alexei B.|date=May 2019|title=New species of the genus Schizolepidopsis (conifers) from the Albian of the Russian high Arctic and geological history of the genus|url=https://linkinghub.elsevier.com/retrieve/pii/S0195667118304257|journal=Cretaceous Research|language=en|volume=97|pages=73–93|doi=10.1016/j.cretres.2019.01.012|bibcode=2019CrRes..97...73D |s2cid=134849082|url-access=subscription}}</ref><ref name="Matsunaga-2021">{{Cite journal|last1=Matsunaga|first1=Kelly K. S.|last2=Herendeen|first2=Patrick S.|last3=Herrera|first3=Fabiany|last4=Ichinnorov|first4=Niiden|last5=Crane|first5=Peter R.|last6=Shi|first6=Gongle|date=2021-05-10|title=Ovulate Cones of Schizolepidopsis ediae sp. nov. Provide Insights into the Evolution of Pinaceae|journal=International Journal of Plant Sciences|volume=182|issue=6|pages=490–507|doi=10.1086/714281|s2cid=235426888|issn=1058-5893|doi-access=free|bibcode=2021IJPlS.182..490M }}</ref> The oldest unambiguous record of Pinaceae is the [[Conifer cone|pine cone]] ''[[Eathiestrobus]]'', known from the Late Jurassic (Kimmeridgian) of Scotland, which remains the only known unequivocal fossil of the group before the Cretaceous.<ref>{{Cite journal|last1=Rothwell|first1=Gar W.|last2=Mapes|first2=Gene|last3=Stockey|first3=Ruth A.|last4=Hilton|first4=Jason|date=April 2012|title=The seed cone Eathiestrobus gen. nov.: Fossil evidence for a Jurassic origin of Pinaceae|journal=American Journal of Botany|language=en|volume=99|issue=4|pages=708–720|doi=10.3732/ajb.1100595|pmid=22491001|bibcode=2012AmJB...99..708R }}</ref> Despite being the earliest known member of the Pinaceae, ''Eathiestrobus'' appears to be a member of the [[Pinoideae|pinoid]] [[clade]] of the family, suggesting that the initial diversification of Pinaceae occurred earlier than has been found in the fossil record.<ref>{{Cite journal|last1=Smith|first1=Selena Y.|last2=Stockey|first2=Ruth A.|last3=Rothwell|first3=Gar W.|last4=Little|first4=Stefan A.|date=2017-01-02|title=A new species of Pityostrobus (Pinaceae) from the Cretaceous of California: moving towards understanding the Cretaceous radiation of Pinaceae|url=https://www.tandfonline.com/doi/full/10.1080/14772019.2016.1143885|journal=Journal of Systematic Palaeontology|language=en|volume=15|issue=1|pages=69–81|doi=10.1080/14772019.2016.1143885|bibcode=2017JSPal..15...69S |s2cid=88292891|issn=1477-2019|url-access=subscription}}</ref><ref name="Leslie-2018" />

The earliest record of the yew family ([[Taxaceae]]) is ''[[Palaeotaxus|Palaeotaxus rediviva]]'', from the Hettangian of Sweden, suggested to be closely related to the living ''[[Austrotaxus]]'', while ''[[Marskea|Marskea jurassica]]'' from the Middle Jurassic of Yorkshire, England and material from the Callovian–Oxfordian [[Daohugou Bed]] in China are thought to be closely related to ''[[Amentotaxus]],'' with the latter material assigned to the modern genus, indicating that Taxaceae had substantially diversified by the end of the Jurassic.<ref>{{Cite journal|last1=Dong|first1=Chong|last2=Shi|first2=Gongle|last3=Herrera|first3=Fabiany|last4=Wang|first4=Yongdong|last5=Herendeen|first5=Patrick S|last6=Crane|first6=Peter R|date=2020-06-18|title=Middle–Late Jurassic fossils from northeastern China reveal morphological stasis in the catkin-yew|journal=National Science Review|volume=7|issue=11|language=en|pages=1765–1767|doi=10.1093/nsr/nwaa138|pmid=34691509|pmc=8288717|issn=2095-5138|doi-access=free}}</ref>

The oldest unambiguous members of [[Podocarpaceae]] are known from the Jurassic, found across both hemispheres, including ''[[Scarburgia]]'' and ''[[Harrisiocarpus]]'' from the Middle Jurassic of England, as well as unnamed species from the Middle-Late Jurassic of Patagonia.<ref>{{Cite journal |last1=Andruchow-Colombo |first1=Ana |last2=Escapa |first2=Ignacio H |last3=Aagesen |first3=Lone |last4=Matsunaga |first4=Kelly K S |date=2023-08-04 |title=In search of lost time: tracing the fossil diversity of Podocarpaceae through the ages |url=https://academic.oup.com/botlinnean/advance-article/doi/10.1093/botlinnean/boad027/7237351 |journal=Botanical Journal of the Linnean Society |volume=203 |issue=4 |pages=315–336 |language=en |doi=10.1093/botlinnean/boad027 |issn=0024-4074|hdl=11336/227952 |hdl-access=free }}</ref>

During the Early Jurassic, the flora of the mid-latitudes of Eastern Asia were dominated by the extinct deciduous broad leafed conifer ''[[Podozamites]],'' which appears to not be closely related to any living family of conifer. Its range extended northwards into polar latitudes of Siberia and then contracted northward in the Middle to Late Jurassic, corresponding to the increasing aridity of the region.<ref>{{Cite journal |last1=Pole |first1=Mike |last2=Wang |first2=Yongdong |last3=Bugdaeva |first3=Eugenia V. |last4=Dong |first4=Chong |last5=Tian |first5=Ning |last6=Li |first6=Liqin |last7=Zhou |first7=Ning |date=2016-12-15 |title=The rise and demise of Podozamites in east Asia—An extinct conifer life style |url=http://www.sciencedirect.com/science/article/pii/S0031018216001188 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |series=Mesozoic ecosystems – Climate and Biota |language=en |volume=464 |pages=97–109 |bibcode=2016PPP...464...97P |doi=10.1016/j.palaeo.2016.02.037 |issn=0031-0182|url-access=subscription }}</ref>

==== Ginkgoales ====
[[File:Ginkgo huttoni 1.jpg|thumb|upright|Leaves of ''[[Ginkgo huttonii]]'' from the Middle Jurassic of England|alt=Black fossils of leaves on yellow coloured rock|left]]
[[Ginkgoales]], of which the sole living species is ''[[Ginkgo biloba]]'', were more diverse during the Jurassic: they were among the most important components of Eurasian Jurassic floras and were adapted to a wide variety of climatic conditions.<ref name="Zhou-2009" /> The earliest representatives of the genus ''[[Ginkgo]],'' represented by [[Ovule|ovulate]] and pollen organs similar to those of the modern species, are known from the Middle Jurassic in the Northern Hemisphere.<ref name="Zhou-2009" /> Several other lineages of ginkgoaleans are known from Jurassic rocks, including ''[[Yimaia]]'', ''[[Grenana]]'', ''[[Nagrenia]]'' and [[Karkeniaceae|''Karkenia'']]. These lineages are associated with ''Ginkgo-''like leaves, but are distinguished from living and fossil representatives of ''Ginkgo'' by having differently arranged reproductive structures.<ref name="Zhou-2009">{{Cite journal|last=Zhou|first=Zhi-Yan|date=March 2009|title=An overview of fossil Ginkgoales|url=https://linkinghub.elsevier.com/retrieve/pii/S1871174X0900002X|journal=Palaeoworld|language=en|volume=18|issue=1|pages=1–22|doi=10.1016/j.palwor.2009.01.001|quote=|url-access=subscription}}</ref><ref>{{Cite journal|last=Nosova|first=Natalya|date=October 2013|title=Revision of the genus Grenana Samylina from the Middle Jurassic of Angren, Uzbekistan|url=https://linkinghub.elsevier.com/retrieve/pii/S0034666713001115|journal=Review of Palaeobotany and Palynology|language=en|volume=197|pages=226–252|doi=10.1016/j.revpalbo.2013.06.005|bibcode=2013RPaPa.197..226N |url-access=subscription}}</ref> ''[[Umaltolepis]]'' from the Jurassic of Asia has strap-shaped ginkgo-like leaves with highly distinct reproductive structures with similarities to those of peltasperm and corystosperm seed ferns, has been suggested to be a member of Ginkgoales ''sensu lato.<ref name="Dong-2022">{{Cite journal |last1=Dong |first1=Chong |last2=Shi |first2=Gongle |last3=Zhang |first3=Xiaoqing |last4=Wang |first4=Zixi |last5=Wang |first5=Yongdong |date=November 2022 |title=Middle-Late Jurassic fossils from Northeast China confirm the affiliation of Umaltolepis seed-bearing structures and Pseudotorellia leaves |url=https://linkinghub.elsevier.com/retrieve/pii/S0034666722001610 |journal=Review of Palaeobotany and Palynology |language=en |volume=306 |article-number=104763 |doi=10.1016/j.revpalbo.2022.104763|bibcode=2022RPaPa.30604763D |s2cid=251917169 |url-access=subscription }}</ref>''

==== Bennettitales ====
[[File:Williamsoniaceae Thérèse Ekblom.webp|thumb|upright=1.15|Restoration of a member of [[Bennettitales]] belonging to Williamsoniaceae.]]
[[Bennettitales]], having first become widespread during the preceding Triassic, were diverse and abundant members of Jurassic floras across both hemispheres.<ref name="Popa-2014">{{Cite journal|last=Popa|first=Mihai E.|date=June 2014|title=Early Jurassic bennettitalean reproductive structures of Romania|url=http://link.springer.com/10.1007/s12549-014-0165-9|journal=Palaeobiodiversity and Palaeoenvironments |language=en |volume=94|issue=2|pages=327–362|doi=10.1007/s12549-014-0165-9|bibcode=2014PdPe...94..327P |s2cid=128411467|issn=1867-1594|url-access=subscription}}</ref> The foliage of Bennettitales bears strong similarities to those of cycads, to such a degree that they cannot be reliably distinguished on the basis of morphology alone. Leaves of Bennettitales can be distinguished from those of cycads their different arrangement of [[stoma]]ta, and the two groups are not thought to be closely related.<ref>{{Citation|last=Taylor|first=T|title=Cycadophytes|date=2009 |url=https://linkinghub.elsevier.com/retrieve/pii/B9780123739728000176|work=Biology and Evolution of Fossil Plants|pages=703–741 |publisher=Elsevier|language=en|doi=10.1016/b978-0-12-373972-8.00017-6|isbn=978-0-12-373972-8|access-date=2020-12-12|url-access=subscription}}</ref> Jurassic Bennettitales predominantly belong to the group [[Williamsoniaceae]],<ref name="Popa-2014" /> which grew as shrubs and small trees. The Williamsoniaceae are thought to have had a [[divaricate]] branching habit, similar to that of living ''[[Banksia]]'', and adapted to growing in open habitats with poor soil nutrient conditions.<ref name="Pott-2014">{{Cite journal|last1=Pott|first1=Christian|last2=McLoughlin|first2=Stephen |date=2014-06-01|title=Divaricate growth habit in Williamsoniaceae (Bennettitales): unravelling the ecology of a key Mesozoic plant group |journal=Palaeobiodiversity and Palaeoenvironments|language=en|volume=94|issue=2|pages=307–325 |doi=10.1007/s12549-014-0157-9|bibcode=2014PdPe...94..307P |s2cid=84440045|issn=1867-1608}}</ref> Bennettitales exhibit complex, [[flower]]-like reproductive structures some of which are thought to have been pollinated by insects. Several groups of insects that bear long proboscis, including extinct families such as [[Kalligrammatidae|kalligrammatid]] lacewings<ref>{{Cite journal|last1=Labandeira|first1=Conrad C. |last2=Yang |first2=Qiang|last3=Santiago-Blay|first3=Jorge A.|last4=Hotton|first4=Carol L.|last5=Monteiro|first5=Antónia|last6=Wang|first6=Yong-Jie |last7=Goreva|first7=Yulia|last8=Shih|first8=ChungKun|last9=Siljeström|first9=Sandra|last10=Rose|first10=Tim R.|last11=Dilcher|first11=David L. |date=2016-02-10|title=The evolutionary convergence of mid-Mesozoic lacewings and Cenozoic butterflies|url= |journal=Proceedings of the Royal Society B: Biological Sciences|language=en|volume=283|issue=1824|article-number=20152893|doi=10.1098/rspb.2015.2893|issn=0962-8452 |pmc=4760178 |pmid=26842570}}</ref> and extant ones such as [[Acroceridae|acrocerid]] flies,<ref>{{Cite journal|last1=Khramov|first1=Alexander V.|author-link1=Alexander V. Khramov|last2=Lukashevich|first2=Elena D.|date=July 2019|title=A Jurassic dipteran pollinator with an extremely long proboscis |url=https://linkinghub.elsevier.com/retrieve/pii/S1342937X1930070X|journal=Gondwana Research|language=en|volume=71|pages=210–215 |doi=10.1016/j.gr.2019.02.004|bibcode=2019GondR..71..210K|s2cid=134847380|url-access=subscription}}</ref> are suggested to have been pollinators of bennettitales, feeding on [[nectar]] produced by bennettitalean cones.

==== Cycads ====
[[Cycad]]s reached their apex of diversity during the Jurassic and Cretaceous Periods.<ref name="Cai-2018">{{Cite journal |last1=Cai |first1=Chenyang |last2=Escalona |first2=Hermes E. |last3=Li |first3=Liqin |last4=Yin |first4=Ziwei |last5=Huang |first5=Diying |last6=Engel |first6=Michael S. |date=September 2018 |title=Beetle Pollination of Cycads in the Mesozoic |journal=Current Biology |language=en |volume=28 |issue=17 |pages=2806–2812.e1 |doi=10.1016/j.cub.2018.06.036 |pmid=30122529|s2cid=52038878|doi-access=free |bibcode=2018CBio...28E2806C }}</ref> Despite the Mesozoic sometimes being called the "Age of Cycads", cycads are thought to have been a relatively minor component of mid-Mesozoic floras, with the Bennettitales and [[Nilssoniales]], which have cycad-like foliage, being dominant.<ref name="Coiro-2017">{{Cite journal |last1=Coiro |first1=Mario |last2=Pott |first2=Christian |date=December 2017|title=Eobowenia gen. nov. from the Early Cretaceous of Patagonia: indication for an early divergence of Bowenia? |journal=BMC Evolutionary Biology |language=en |volume=17 |issue=1 |page=97 |doi=10.1186/s12862-017-0943-x|issn=1471-2148 |pmc=5383990 |pmid=28388891 |doi-access=free |bibcode=2017BMCEE..17...97C }}</ref> The Nilssoniales have often been considered cycads or cycad relatives, but have been found to be distinct on chemical grounds, and perhaps more closely allied with Bennettitales.''<ref name="Vajda-2017">{{Cite journal |last1=Vajda |first1=Vivi |last2=Pucetaite |first2=Milda |last3=McLoughlin |first3=Stephen |last4=Engdahl |first4=Anders |last5=Heimdal |first5=Jimmy |last6=Uvdal |first6=Per |date=August 2017 |title=Molecular signatures of fossil leaves provide unexpected new evidence for extinct plant relationships |url=https://www.nature.com/articles/s41559-017-0224-5 |journal=Nature Ecology & Evolution |language=en |volume=1 |issue=8 |pages=1093–1099 |doi=10.1038/s41559-017-0224-5 |issn=2397-334X |pmid=29046567 |bibcode=2017NatEE...1.1093V |s2cid=3604369}}</ref>'' The relationships of most Mesozoic cycads to living groups are ambiguous,<ref name="Coiro-2017" /> with no Jurassic cycads belonging to either of the two modern groups of cycads, though some Jurassic cycads possibly represent [[stem-group]] relatives of modern [[Cycadaceae]], like the leaf genus ''[[Paracycas]]'' known Europe, and [[Zamiaceae]], like some European species of the leaf genus ''[[Pseudoctenis]]''. Also widespread during the Jurassic was the extinct ''[[Ctenis]]'' lineage, which appears to be distantly related to modern cycads.<ref>{{Cite journal |last1=Coiro |first1=Mario |last2=Allio |first2=Rémi |last3=Mazet |first3=Nathan |last4=Seyfullah |first4=Leyla J. |last5=Condamine |first5=Fabien L. |date=2023-06-11 |title=Reconciling fossils with phylogenies reveals the origin and macroevolutionary processes explaining the global cycad biodiversity |journal=New Phytologist |volume=240 |issue=4 |pages=1616–1635 |language=en |doi=10.1111/nph.19010 |pmid=37302411 |s2cid=259137975 |issn=0028-646X|doi-access=free |pmc=10953041 |bibcode=2023NewPh.240.1616C }}</ref> Modern cycads are pollinated by beetles, and such an association is thought to have formed by the Early Jurassic.<ref name="Cai-2018" />

==== Other seed plants ====
Although there have been several claimed records, there are no widely accepted Jurassic fossil records of [[flowering plant]]s, which make up 90% of living plant species, and fossil evidence suggests that the group diversified during the following Cretaceous.<ref>{{Cite journal|last=Bateman|first=Richard M|date=2020-01-01|editor-last=Ort|editor-first=Donald|title=Hunting the Snark: the flawed search for mythical Jurassic angiosperms|url=https://academic.oup.com/jxb/article/71/1/22/5571867|journal=Journal of Experimental Botany|language=en|volume=71|issue=1|pages=22–35|doi=10.1093/jxb/erz411|issn=0022-0957|pmid=31538196|url-access=subscription}}</ref>

The earliest known [[gnetophytes]], one of the four main living groups of [[gymnosperm]]s, appeared by the end of the Jurassic, with the oldest unequivocal gnetophyte being the seed ''[[Dayvaultia]]'' from the Late Jurassic of North America.<ref name="Coiro-2022">{{Cite journal |last1=Coiro |first1=Mario |last2=Roberts |first2=Emily A. |last3=Hofmann |first3=Christa-Ch. |last4=Seyfullah |first4=Leyla J. |date=2022-12-14 |title=Cutting the long branches: Consilience as a path to unearth the evolutionary history of Gnetales |journal=Frontiers in Ecology and Evolution |volume=10 |article-number=1082639 |doi=10.3389/fevo.2022.1082639 |issn=2296-701X |doi-access=free |bibcode=2022FrEEv..1082639C }}</ref>[[File:Sagenopteris_restoration.jpg|thumb|Life restoration of the stem and leaves of a member of the extinct seed plant order [[Caytoniales]], a group which reached its apex of abundance during the Jurassic, and which may be closely related to living [[flowering plant]]s.]]
"Seed ferns" ([[Pteridospermatophyta]]) is a collective term to refer to disparate lineages of fern like plants that produce seeds but have uncertain affinities to living [[Spermatophyte|seed plant]] groups. A prominent group of Jurassic seed ferns is the [[Caytoniales]], which reached their zenith during the Jurassic, with widespread records in the Northern Hemisphere, though records in the Southern Hemisphere remain rare. Due to their [[berry]]-like seed-bearing capsules, they have often been suggested to have been closely related or perhaps ancestral to flowering plants, but the evidence for this is inconclusive.<ref>{{Cite journal|last1=Elgorriaga|first1=Andrés|last2=Escapa|first2=Ignacio H.|last3=Cúneo|first3=N. Rubén|date=2019-09-02|title=Southern Hemisphere Caytoniales: vegetative and reproductive remains from the Lonco Trapial Formation (Lower Jurassic), Patagonia|url=https://www.tandfonline.com/doi/full/10.1080/14772019.2018.1535456|journal=Journal of Systematic Palaeontology|language=en|volume=17|issue=17|pages=1477–1495|doi=10.1080/14772019.2018.1535456|bibcode=2019JSPal..17.1477E |s2cid=92287804|issn=1477-2019|url-access=subscription}}</ref> [[Corystospermaceae|Corystosperm]]-aligned seed ferns, such as ''[[Pachypteris]]'' and ''[[Komlopteris]]'' were widespread across both hemispheres during the Jurassic.<ref>{{Cite journal |last1=Slodownik |first1=Miriam |last2=Hill |first2=Robert S. |last3=McLoughlin |first3=Stephen |date=October 2023 |title=Komlopteris: A persistent lineage of post-Triassic corystosperms in Gondwana |journal=Review of Palaeobotany and Palynology |language=en |volume=317 |article-number=104950 |doi=10.1016/j.revpalbo.2023.104950|bibcode=2023RPaPa.31704950S |s2cid=260015702 |doi-access=free }}</ref>

[[Czekanowskiales]], also known as Leptostrobales, are a group of seed plants uncertain affinities with persistent heavily dissected leaves borne on deciduous short shoots, subtended by scale-like leaves, known from the Late Triassic (possibly Late Permian<ref name="Kustatscher-2019">{{Cite journal|last1=Kustatscher|first1=Evelyn|last2=Visscher|first2=Henk|last3=van Konijnenburg-van Cittert|first3=Johanna H. A.|date=2019-09-01|title=Did the Czekanowskiales already exist in the late Permian?|journal=PalZ|language=en|volume=93|issue=3|pages=465–477|doi=10.1007/s12542-019-00468-9|s2cid=199473893|issn=1867-6812|doi-access=free|bibcode=2019PalZ...93..465K }}</ref>) to Cretaceous.<ref name="Taylor-2009">{{Citation|last=Taylor|first=T|title=Gymnosperms with obscure affinities|date=2009|url=https://linkinghub.elsevier.com/retrieve/pii/B978012373972800019X|work=Biology and Evolution of Fossil Plants|pages=757–785|publisher=Elsevier|language=en|doi=10.1016/b978-0-12-373972-8.00019-x|isbn=978-0-12-373972-8|access-date=2020-12-13|url-access=subscription}}</ref> They are thought to have had a tree- or shrub-like habit and formed a conspicuous component of Northern Hemisphere Mesozoic temperate and warm-temperate floras.<ref name="Kustatscher-2019" /> The genus ''[[Phoenicopsis]]'' was widespread in Early-Middle Jurassic floras of Eastern Asia and Siberia.<ref>{{Cite journal|last1=Sun|first1=Chunlin|last2=Li|first2=Yunfeng|last3=Dilcher|first3=David L.|last4=Wang|first4=Hongshan|last5=Li|first5=Tao|last6=Na|first6=Yuling|last7=Wang|first7=Anping|date=November 2015|title=An introductory report on the biodiversity of Middle Jurassic Phoenicopsis (Czekanowskiales) from the Ordos Basin, China|url=https://linkinghub.elsevier.com/retrieve/pii/S2095927316302869|journal=Science Bulletin|language=en|volume=60|issue=21|pages=1858–1865|doi=10.1007/s11434-015-0904-y|bibcode=2015SciBu..60.1858S|s2cid=140617907|url-access=subscription}}</ref>

The [[Pentoxylales]], a small but clearly distinct group of [[liana]]-like seed plants of obscure affinities, first appeared during the Jurassic. Their distribution appears to have been confined to Eastern Gondwana.<ref>Pattemore, G.A., Rigby, J.F. and Playford, G., 2015. Triassic-Jurassic pteridosperms of Australasia: speciation, diversity and decline. Boletín Geológico y Minero, 126 (4): 689–722</ref>

==== Ferns and allies ====
Living families of ferns widespread during the Jurassic include [[Dipteridaceae]], [[Matoniaceae]], [[Gleicheniaceae]], [[Osmundaceae]] and [[Marattiaceae]].<ref>{{Cite journal|last=Skog|first=Judith E.|date=April 2001|title=Biogeography of Mesozoic leptosporangiate ferns related to extant ferns|journal=Brittonia|volume=53|issue=2|pages=236–269|doi=10.1007/bf02812701|bibcode=2001Britt..53..236S |s2cid=42781830|issn=0007-196X}}</ref><ref>{{Cite journal|last1=Tian|first1=Ning|last2=Wang|first2=Yong-Dong|last3=Zhang|first3=Wu|last4=Zheng|first4=Shao-Lin|last5=Zhu|first5=Zhi-Peng|last6=Liu|first6=Zhong-Jian|date=2018-03-01|title=Permineralized osmundaceous and gleicheniaceous ferns from the Jurassic of Inner Mongolia, NE China|journal=Palaeobiodiversity and Palaeoenvironments|language=en|volume=98|issue=1|pages=165–176|doi=10.1007/s12549-017-0313-0|bibcode=2018PdPe...98..165T |issn=1867-1608|s2cid=134149095}}</ref> [[Polypodiales]], which make up 80% of living fern diversity, have no record from the Jurassic and are thought to have diversified in the Cretaceous,<ref>{{Cite journal|last1=Regalado|first1=Ledis|last2=Schmidt|first2=Alexander R.|last3=Müller|first3=Patrick|last4=Niedermeier|first4=Lisa|last5=Krings|first5=Michael|last6=Schneider|first6=Harald|date=July 2019|title=Heinrichsia cheilanthoides gen. et sp. nov., a fossil fern in the family Pteridaceae (Polypodiales) from the Cretaceous amber forests of Myanmar|journal=Journal of Systematics and Evolution|language=en|volume=57|issue=4|pages=329–338|doi=10.1111/jse.12514|issn=1674-4918|doi-access=free|bibcode=2019JSyEv..57..329R |s2cid=182754946}}</ref> though the widespread Jurassic [[Herbaceous plant|herbaceous]] fern genus ''[[Coniopteris]],'' historically interpreted as a close relative of [[tree fern]]s of the family [[Dicksoniaceae]], has recently been reinterpreted as an early relative of the group.<ref name="Coniopteris">{{Cite journal|last1=Li|first1=Chunxiang|last2=Miao|first2=Xinyuan|last3=Zhang|first3=Li-Bing|last4=Ma|first4=Junye|last5=Hao|first5=Jiasheng|date=January 2020|title=Re-evaluation of the systematic position of the Jurassic–Early Cretaceous fern genus Coniopteris|url=https://linkinghub.elsevier.com/retrieve/pii/S0195667118303033|journal=Cretaceous Research|language=en|volume=105|article-number=104136|doi=10.1016/j.cretres.2019.04.007|bibcode=2020CrRes.10504136L |s2cid=146355798|url-access=subscription}}</ref>

The [[Cyatheales]], the group containing most modern tree ferns, appeared during the Late Jurassic, represented by members of the genus ''[[Cyathocaulis]]'', which are suggested to be early members of [[Cyatheaceae]] on the basis of cladistic analysis.<ref>{{Cite journal |last1=Korall |first1=Petra |last2=Pryer |first2=Kathleen M. |date=February 2014 |editor-last=Parmakelis |editor-first=Aristeidis |title=Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal |journal=Journal of Biogeography |language=en |volume=41 |issue=2 |pages=402–413 |doi=10.1111/jbi.12222 |issn=0305-0270 |pmc=4238398 |pmid=25435648|bibcode=2014JBiog..41..402K }}</ref> Only a handful of possible records exist of the [[Hymenophyllaceae]] from the Jurassic, including ''Hymenophyllites macrosporangiatus'' from the Russian Jurassic.<ref>{{Cite journal|last1=Axsmith|first1=Brian J.|last2=Krings|first2=Michael|last3=Taylor|first3=Thomas N.|date=September 2001|title=A filmy fern from the Upper Triassic of North Carolina (USA)|journal=American Journal of Botany|volume=88|issue=9|pages=1558–1567|doi=10.2307/3558399|issn=0002-9122|jstor=3558399|pmid=21669688|doi-access=free|bibcode=2001AmJB...88.1558A }}</ref>

The oldest remains of modern [[Equisetaceae|horsetails]] of the genus ''[[Equisetum]]'' first appear in the Early Jurassic, represented by ''[[Equisetum dimorphum]]'' from the Early Jurassic of Patagonia<ref>{{Cite journal|last1=Elgorriaga|first1=Andrés|last2=Escapa|first2=Ignacio H.|last3=Bomfleur|first3=Benjamin|last4=Cúneo|first4=Rubén|last5=Ottone|first5=Eduardo G.|date=February 2015|title=Reconstruction and Phylogenetic Significance of a New Equisetum Linnaeus Species from the Lower Jurassic of Cerro Bayo (Chubut Province, Argentina)|url=http://www.bioone.org/doi/10.5710/AMGH.15.09.2014.2758|journal=Ameghiniana|language=en|volume=52|issue=1|pages=135–152|doi=10.5710/AMGH.15.09.2014.2758|bibcode=2015Amegh..52..135E |issn=0002-7014|s2cid=6134534|hdl=11336/66623|hdl-access=free}}</ref> and ''[[Equisetum laterale]]'' from the Early to Middle Jurassic of Australia.<ref>Gould, R. E. 1968. Morphology of ''Equisetum laterale'' Phillips, 1829, and ''E. bryanii'' sp. nov. from the Mesozoic of south‐eastern Queensland. Australian Journal of Botany 16: 153–176.</ref><ref name="Elgorriaga-2018">{{Cite journal|last1=Elgorriaga|first1=Andrés|last2=Escapa|first2=Ignacio H.|last3=Rothwell|first3=Gar W.|last4=Tomescu|first4=Alexandru M. F.|last5=Rubén Cúneo|first5=N.|date=August 2018|title=Origin of Equisetum: Evolution of horsetails (Equisetales) within the major euphyllophyte clade Sphenopsida|journal=American Journal of Botany|language=en|volume=105|issue=8|pages=1286–1303|doi=10.1002/ajb2.1125|pmid=30025163|doi-access=free}}</ref> [[Petrifaction|Silicified]] remains of ''[[Equisetum thermale]]'' from the Late Jurassic of Argentina exhibit all the morphological characters of modern members of the genus.<ref>{{Cite journal|last1=Channing|first1=Alan|last2=Zamuner|first2=Alba|last3=Edwards|first3=Dianne|last4=Guido|first4=Diego|date=2011|title=Equisetum thermale sp. nov. (Equisetales) from the Jurassic San Agustín hot spring deposit, Patagonia: Anatomy, paleoecology, and inferred paleoecophysiology|journal=American Journal of Botany|language=en|volume=98|issue=4|pages=680–697|doi=10.3732/ajb.1000211|issn=1537-2197|pmid=21613167|doi-access=free|bibcode=2011AmJB...98..680C |hdl=11336/95234|hdl-access=free}}</ref> The estimated split between ''[[Equisetum bogotense]]'' and all other living ''Equisetum'' is estimated to have occurred no later than the Early Jurassic.<ref name="Elgorriaga-2018" />

==== Lower plants ====
[[Isoetes|Quillworts]] virtually identical to modern species are known from the Jurassic onwards. ''[[Isoetites rolandii]]'' from the Middle Jurassic of Oregon is the earliest known species to represent all major morphological features of modern ''Isoetes''. More primitive forms such as ''[[Nathorstiana]],'' which retain an elongated stem, persisted into the Early Cretaceous.<ref>{{Cite journal|last1=Wood|first1=Daniel|last2=Besnard|first2=Guillaume|last3=Beerling|first3=David J.|last4=Osborne|first4=Colin P.|last5=Christin|first5=Pascal-Antoine|date=2020-06-18|title=Phylogenomics indicates the "living fossil" Isoetes diversified in the Cenozoic|journal=PLOS ONE|language=en|volume=15|issue=6|article-number=e0227525|doi=10.1371/journal.pone.0227525|issn=1932-6203|pmc=7302493|pmid=32555586|bibcode=2020PLoSO..1527525W|doi-access=free}}</ref>

The moss ''[[Kulindobryum]]'' from the Middle Jurassic of Russia, which was found associated with dinosaur bones, is thought to be related to the [[Splachnaceae]], which grow on animal caracasses.<ref name="Mamontov-2019" /> ''[[Bryokhutuliinia]]'' from the same region is thought to be related to [[Dicranales]].<ref name="Mamontov-2019">{{Cite journal|last1=Mamontov|first1=Yuriy S.|last2=Ignatov|first2=Michael S.|date=July 2019|title=How to rely on the unreliable: Examples from Mesozoic bryophytes of Transbaikalia|journal=Journal of Systematics and Evolution|language=en|volume=57|issue=4|pages=339–360|doi=10.1111/jse.12483|s2cid=92268163|issn=1674-4918|doi-access=free|bibcode=2019JSyEv..57..339M }}</ref> ''[[Heinrichsiella]]'' from the Jurassic of Patagonia is thought to belong to either [[Polytrichaceae]] or [[Timmiellaceae]].<ref>{{Cite journal|last1=Bippus|first1=Alexander C.|last2=Savoretti|first2=Adolfina|last3=Escapa|first3=Ignacio H.|last4=Garcia-Massini|first4=Juan|last5=Guido|first5=Diego|date=October 2019|title=Heinrichsiella patagonica gen. et sp. nov.: A Permineralized Acrocarpous Moss from the Jurassic of Patagonia|journal=International Journal of Plant Sciences|volume=180|issue=8|pages=882–891|doi=10.1086/704832|bibcode=2019IJPlS.180..882B |s2cid=202859471|issn=1058-5893}}</ref>

The liverwort ''[[Pellites|Pellites hamiensis]]'' from the Middle Jurassic [[Xishanyao Formation]] of China is the oldest record of the family [[Pelliaceae]].<ref>{{Cite journal|last1=Li|first1=Ruiyun|last2=Li|first2=Xiaoqiang|last3=Deng|first3=Shenghui|last4=Sun|first4=Bainian|date=August 2020|title=Morphology and microstructure of Pellites hamiensis nov. sp., a Middle Jurassic liverwort from northwestern China and its evolutionary significance|url=https://linkinghub.elsevier.com/retrieve/pii/S001669952030070X|journal=Geobios|volume=62|language=en|pages=23–29|doi=10.1016/j.geobios.2020.07.003|bibcode=2020Geobi..62...23L |s2cid=225500594|url-access=subscription}}</ref> [[Pallaviciniites|''Pallaviciniites sandaolingensis'']] from the same deposit is thought to belong to the subclass Pallaviciniineae within the [[Pallaviciniales]].<ref>{{Cite journal|last1=Li|first1=Rui-Yun|last2=Wang|first2=Xue-lian|last3=Chen|first3=Jing-Wei|last4=Deng|first4=Sheng-Hui|last5=Wang|first5=Zi-Xi|last6=Dong|first6=Jun-Ling|last7=Sun|first7=Bai-Nian|date=June 2016|title=A new thalloid liverwort: Pallaviciniites sandaolingensis sp. nov. from the Middle Jurassic of Turpan–Hami Basin, NW China|url=http://link.springer.com/10.1007/s12542-016-0299-3|journal=PalZ|language=en|volume=90|issue=2|pages=389–397|doi=10.1007/s12542-016-0299-3|bibcode=2016PalZ...90..389L |s2cid=131295547|issn=0031-0220|url-access=subscription}}</ref> ''[[Ricciopsis|Ricciopsis sandaolingensis]]'', also from the same deposit, is the only Jurassic record of [[Ricciaceae]].<ref>{{Cite journal|last1=Li|first1=Ruiyun|last2=Li|first2=Xiaoqiang|last3=Wang|first3=Hongshan|last4=Sun|first4=Bainian|date=2019|title=Ricciopsis sandaolingensis sp. nov., a new fossil bryophyte from the Middle Jurassic Xishanyao Formation in the Turpan-Hami Basin, Xinjiang, Northwest China|journal=Palaeontologia Electronica|volume=22|issue=2|page=917 |doi=10.26879/917|issn=1094-8074|doi-access=free|bibcode=2019PalEl..22..917L }}</ref>

==Fauna==

=== Dinosaurs ===
[[Dinosaur]]s, which had morphologically diversified in the Late Triassic, experienced a major increase in diversity and abundance during the Early Jurassic in the aftermath of the end-Triassic extinction and the extinction of other reptile groups, becoming the dominant vertebrates in terrestrial ecosystems.<ref>{{Cite journal |last1=Brusatte |first1=Stephen L |last2=Benton |first2=Michael J |last3=Ruta |first3=Marcello |last4=Lloyd |first4=Graeme T |date=2008-12-23 |title=The first 50 Myr of dinosaur evolution: macroevolutionary pattern and morphological disparity |url= |journal=Biology Letters |volume=4 |issue=6 |pages=733–736 |doi=10.1098/rsbl.2008.0441 |pmc=2614175 |pmid=18812311}}</ref><ref name="Brusatte">{{cite journal |last1=Brusatte |first1=S. L. |last2=Benton |first2=M. J. |last3=Ruta |first3=M. |last4=Lloyd |first4=G. T. |date=2008-09-12 |title=Superiority, Competition, and Opportunism in the Evolutionary Radiation of Dinosaurs |url=http://palaeo.gly.bris.ac.uk/Benton/reprints/2008Science.pdf |journal=[[Science (journal)|Science]] |volume=321 |issue=5895 |pages=1485–88 |bibcode=2008Sci...321.1485B |doi=10.1126/science.1161833 |pmid=18787166 |s2cid=13393888 |archive-url=https://web.archive.org/web/20140624204033/http://palaeo.gly.bris.ac.uk/Benton/reprints/2008Science.pdf |archive-date=2014-06-24 |access-date=2012-01-14 |hdl=20.500.11820/00556baf-6575-44d9-af39-bdd0b072ad2b}}</ref> ''[[Chilesaurus]]'', a morphologically aberrant herbivorous dinosaur from the Late Jurassic of South America, has uncertain relationships to the three main groups of dinosaurs, having been recovered as a member of all three in different analyses.<ref>{{Cite journal |last1=Temp Müller |first1=Rodrigo |last2=Augusto Pretto |first2=Flávio |last3=Kerber |first3=Leonardo |last4=Silva-Neves |first4=Eduardo |last5=Dias-da-Silva |first5=Sérgio |date=28 March 2018 |title=Comment on 'A dinosaur missing-link? Chilesaurus and the early evolution of ornithischian dinosaurs' |url= |journal=Biology Letters |language=en |volume=14 |issue=3 |article-number=20170581 |doi=10.1098/rsbl.2017.0581 |issn=1744-9561 |pmc=5897605 |pmid=29593074}}</ref>

==== Theropods ====
Advanced [[Theropoda|theropods]] belonging to [[Neotheropoda]] first appeared in the Late Triassic. Basal neotheropods, such as [[Coelophysoidea|coelophysoids]] and [[Dilophosauridae|dilophosaurs]], persisted into the Early Jurassic, but became extinct by the Middle Jurassic.<ref>{{Cite journal |last1=Zahner |first1=Marion |last2=Brinkmann |first2=Winand |date=August 2019 |title=A Triassic averostran-line theropod from Switzerland and the early evolution of dinosaurs |url= |journal=Nature Ecology & Evolution |language=en |volume=3 |issue=8 |pages=1146–1152 |bibcode=2019NatEE...3.1146Z |doi=10.1038/s41559-019-0941-z |issn=2397-334X |pmc=6669044 |pmid=31285577}}</ref> The earliest [[averostra]]ns appear during the Early Jurassic, with the earliest known member of [[Ceratosauria]] being ''[[Saltriovenator]]'' from the early Sinemurian (199.3–197.5 Ma) of Italy.<ref>{{Cite journal |last1=Sasso |first1=Cristiano Dal |last2=Maganuco |first2=Simone |last3=Cau |first3=Andrea |date=2018-12-19 |title=The oldest ceratosaurian (Dinosauria: Theropoda), from the Lower Jurassic of Italy, sheds light on the evolution of the three-fingered hand of birds |journal=PeerJ |language=en |volume=6 |article-number=e5976 |doi=10.7717/peerj.5976 |issn=2167-8359 |pmc=6304160 |pmid=30588396 |doi-access=free}}</ref> The unusual ceratosaur ''[[Limusaurus]]'' from the Late Jurassic of China had a herbivorous diet, with adults having [[edentulous]] beaked jaws,<ref>{{Cite journal |last1=Wang |first1=Shuo |last2=Stiegler |first2=Josef |last3=Amiot |first3=Romain |last4=Wang |first4=Xu |last5=Du |first5=Guo-hao |last6=Clark |first6=James M. |last7=Xu |first7=Xing |date=January 2017 |title=Extreme Ontogenetic Changes in a Ceratosaurian Theropod |journal=Current Biology |language=en |volume=27 |issue=1 |pages=144–148 |bibcode=2017CBio...27..144W |doi=10.1016/j.cub.2016.10.043 |pmid=28017609 |s2cid=441498 |doi-access=free}}</ref> making it the earliest known theropod to have converted from an ancestrally carnivorous diet.<ref>{{Cite journal |last1=Zanno |first1=Lindsay E. |last2=Makovicky |first2=Peter J. |date=2011-01-04 |title=Herbivorous ecomorphology and specialization patterns in theropod dinosaur evolution |journal=Proceedings of the National Academy of Sciences |language=en |volume=108 |issue=1 |pages=232–237 |bibcode=2011PNAS..108..232Z |doi=10.1073/pnas.1011924108 |issn=0027-8424 |pmc=3017133 |pmid=21173263 |doi-access=free}}</ref> The earliest members of the [[Tetanurae]] appeared during the late Early Jurassic or early Middle Jurassic.<ref name="Rauhut-2019">{{Cite journal |last1=Rauhut |first1=Oliver W. M. |last2=Pol |first2=Diego |date=2019-12-11 |title=Probable basal allosauroid from the early Middle Jurassic Cañadón Asfalto Formation of Argentina highlights phylogenetic uncertainty in tetanuran theropod dinosaurs |journal=Scientific Reports |language=en |volume=9 |issue=1 |page=18826 |bibcode=2019NatSR...918826R |doi=10.1038/s41598-019-53672-7 |issn=2045-2322 |pmc=6906444 |pmid=31827108 |doi-access=free}}</ref> The [[Megalosauridae]] represent the oldest radiation of the Tetanurae, first appearing in Europe during the Bajocian.<ref name="Benson-2010">{{Cite journal |last=Benson |first=R.B.J |date=2010 |title=A description of Megalosaurus bucklandii (Dinosauria: Theropoda) from the Bathonian of the UK and the relationships of Middle Jurassic theropods |journal=Zoological Journal of the Linnean Society |volume=158 |issue=4 |pages=882–935 |doi=10.1111/j.1096-3642.2009.00569.x |doi-access=free}}</ref> The oldest member of [[Allosauroidea]] has been suggested to be ''[[Asfaltovenator]]'' from the Middle Jurassic of South America.<ref name="Rauhut-2019" /> [[Coelurosauria|Coelurosaurs]] first appeared during the Middle Jurassic, including early [[Tyrannosauroidea|tyrannosaurs]] such as ''[[Proceratosaurus]]'' from the Bathonian of Britain.<ref name="rauhutetal2010">{{Cite journal |last1=Rauhut |first1=Oliver W. M. |last2=Milner |first2=Angela C. |last3=Moore-Fay |first3=Scott |year=2010 |title=Cranial osteology and phylogenetic position of the theropod dinosaur ''Proceratosaurus'' bradleyi(Woodward, 1910) from the Middle Jurassic of England |journal=Zoological Journal of the Linnean Society |volume=158 |pages=155–195 |doi=10.1111/j.1096-3642.2009.00591.x |doi-access=free}}</ref> Some coelurosaurs from the Late Jurassic of China including ''[[Shishugounykus]]'' and ''[[Haplocheirus]]'' are suggested to represent early [[Alvarezsauroidea|alvarezsaurs]],<ref>Qin, Z., Clark, J., Choiniere, J., & Xu, X. (2019). A new alvarezsaurian theropod from the Upper Jurassic Shishugou Formation of western China. Scientific Reports, 9: 11727. {{doi|10.1038/s41598-019-48148-7}}</ref> however, this has been questioned.<ref>{{Cite journal |last1=Agnolín |first1=Federico L. |last2=Lu |first2=Jun-Chang |last3=Kundrát |first3=Martin |last4=Xu |first4=Li |date=2021-06-02 |title=Alvarezsaurid osteology: new data on cranial anatomy |url=https://www.tandfonline.com/doi/full/10.1080/08912963.2021.1929203 |journal=Historical Biology |language=en |volume=34 |issue=3 |pages=443–452 |doi=10.1080/08912963.2021.1929203 |issn=0891-2963 |s2cid=236221732|url-access=subscription }}</ref> [[Scansoriopterygidae|Scansoriopterygids]], a group of small feathered coelurosaurs with membraneous, bat-like wings for gliding, are known from the Middle to Late Jurassic of China.<ref>{{Cite journal |last1=Wang |first1=Min |last2=O'Connor |first2=Jingmai K. |last3=Xu |first3=Xing |last4=Zhou |first4=Zhonghe |date=May 2019 |title=A new Jurassic scansoriopterygid and the loss of membranous wings in theropod dinosaurs |url=https://www.nature.com/articles/s41586-019-1137-z |journal=Nature |language=en |volume=569 |issue=7755 |pages=256–259 |bibcode=2019Natur.569..256W |doi=10.1038/s41586-019-1137-z |issn=1476-4687 |pmid=31068719 |s2cid=148571099|url-access=subscription }}</ref> The oldest record of [[Troodontidae|troodontids]] is suggested to be ''[[Hesperornithoides]]'' from the Late Jurassic of North America. Tooth remains suggested to represent those of [[Dromaeosauridae|dromaeosaurs]] are known from the Jurassic, but no body remains are known until the Cretaceous.<ref>{{Cite journal |last1=Hartman |first1=Scott |last2=Mortimer |first2=Mickey |last3=Wahl |first3=William R. |last4=Lomax |first4=Dean R. |last5=Lippincott |first5=Jessica |last6=Lovelace |first6=David M. |date=2019-07-10 |title=A new paravian dinosaur from the Late Jurassic of North America supports a late acquisition of avian flight |journal=PeerJ |language=en |volume=7 |article-number=e7247 |doi=10.7717/peerj.7247 |issn=2167-8359 |pmc=6626525 |pmid=31333906 |doi-access=free}}</ref>

<gallery>
File:Ceratosaurus mounted white background.jpg|Skeleton of ''[[Ceratosaurus]]'', a ceratosaurid from the Late Jurassic of North America
File:Monolophosaurus jiangi.jpg|Skeleton of ''[[Monolophosaurus]]'', a basal tetanuran from the Middle Jurassic of China
File:Yi qi restoration.jpg|Restoration of ''[[Yi (dinosaur)|Yi qi]]'', a scansoriopterygid from the Middle to Late Jurassic of China
</gallery>

===== Birds =====
[[File:Archaeopteryx lithographica (Berlin specimen).jpg|thumb|upright|''[[Archaeopteryx|Archaeopteryx lithographica]]'' from the Late Jurassic (Tithonian) of Germany|alt=Fossil of complete Archaeopteryx, including indentations of feathers on wings and tail]]
The earliest [[Avialae|avialans]], which include birds and their ancestors, appear during the Middle to Late Jurassic, definitively represented by ''[[Archaeopteryx]]'' from the Late Jurassic of Germany. Avialans belong to the clade [[Paraves]] within Coelurosauria, which also includes dromaeosaurs and troodontids. The [[Anchiornithidae]] from the Middle-Late Jurassic of Eurasia have frequently suggested to be avialans, but have also alternatively found as a separate lineage of paravians.<ref name="Rauhut-2020">{{Citation |last1=Rauhut |first1=Oliver W. M. |title=The Origin of Birds: Current Consensus, Controversy, and the Occurrence of Feathers |date=2020 |work=The Evolution of Feathers: From Their Origin to the Present |pages=27–45 |editor-last=Foth |editor-first=Christian |series=Fascinating Life Sciences |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-27223-4_3 |isbn=978-3-030-27223-4 |s2cid=216372010 |last2=Foth |first2=Christian |editor2-last=Rauhut |editor2-first=Oliver W. M.}}</ref>
[[File:Heterodontosaurus tucki cast - University of California Museum of Paleontology - Berkeley, CA - DSC04696.JPG|left|thumb|Skeleton of ''[[Heterodontosaurus]],'' a primitive ornithischian from the Early Jurassic of South Africa]]

==== Ornithischians ====
The earliest definitive [[ornithischia]]ns appear during the Early Jurassic, represented by basal ornithischians like ''[[Lesothosaurus]]'', [[Heterodontosauridae|heterodontosaurids]], and early members of [[Thyreophora]]. The earliest members of [[Ankylosauria]] and [[Stegosauria]] appear during the Middle Jurassic.<ref>{{Cite journal |last=Norman |first=David B |date=2021-01-01 |title=Scelidosaurus harrisonii (Dinosauria: Ornithischia) from the Early Jurassic of Dorset, England: biology and phylogenetic relationships |url=https://academic.oup.com/zoolinnean/article/191/1/1/5893854 |journal=Zoological Journal of the Linnean Society |language=en |volume=191 |issue=1 |pages=1–86 |doi=10.1093/zoolinnean/zlaa061 |issn=0024-4082|url-access=subscription }}</ref> The basal [[neornithischia]]n ''[[Kulindadromeus]]'' from the Middle Jurassic of Russia indicates that at least some ornithischians were covered in [[Feathered dinosaur|protofeathers]].<ref>{{Citation |last1=Godefroit |first1=Pascal |title=Integumentary Structures in Kulindadromeus zabaikalicus, a Basal Neornithischian Dinosaur from the Jurassic of Siberia |date=2020 |work=The Evolution of Feathers: From Their Origin to the Present |pages=47–65 |editor-last=Foth |editor-first=Christian |series=Fascinating Life Sciences |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-030-27223-4_4 |isbn=978-3-030-27223-4 |s2cid=216261986 |last2=Sinitsa |first2=Sofia M. |last3=Cincotta |first3=Aude |last4=McNamara |first4=Maria E. |last5=Reshetova |first5=Svetlana A. |last6=Dhouailly |first6=Danielle |editor2-last=Rauhut |editor2-first=Oliver W. M.}}</ref> The earliest members of [[Ankylopollexia]], which become prominent in the Cretaceous, appeared during the Late Jurassic, represented by bipedal forms such as ''[[Camptosaurus]]''.<ref>{{Cite journal |last=McDonald |first=Andrew T. |date=2012-05-22 |editor-last=Farke |editor-first=Andrew A. |title=Phylogeny of Basal Iguanodonts (Dinosauria: Ornithischia): An Update |journal=PLOS ONE |language=en |volume=7 |issue=5 |article-number=e36745 |bibcode=2012PLoSO...736745M |doi=10.1371/journal.pone.0036745 |issn=1932-6203 |pmc=3358318 |pmid=22629328 |doi-access=free}}</ref> [[Ceratopsia]]ns first appeared in the Late Jurassic of China, represented by members of [[Chaoyangsauridae]].<ref>{{Cite journal |last1=Han |first1=Fenglu |last2=Forster |first2=Catherine A. |last3=Clark |first3=James M. |last4=Xu |first4=Xing |date=2015-12-09 |title=A New Taxon of Basal Ceratopsian from China and the Early Evolution of Ceratopsia |journal=PLOS ONE |language=en |volume=10 |issue=12 |article-number=e0143369 |bibcode=2015PLoSO..1043369H |doi=10.1371/journal.pone.0143369 |issn=1932-6203 |pmc=4674058 |pmid=26649770 |doi-access=free}}</ref>

==== Sauropodomorphs ====
[[File:Mamenchisaurus in Japan.jpg|left|thumb|Skeleton of ''[[Mamenchisaurus|Mamenchisaurus sinocanadorum]]'' from the Middle-Late Jurassic of China]]
[[Sauropoda|Sauropods]] became the dominant large herbivores in terrestrial ecosystems during the Jurassic.<ref name="Pol-2020">{{Cite journal |last1=Pol |first1=D. |last2=Ramezani |first2=J. |last3=Gomez |first3=K. |last4=Carballido |first4=J. L. |last5=Carabajal |first5=A. Paulina |last6=Rauhut |first6=O. W. M. |last7=Escapa |first7=I. H. |last8=Cúneo |first8=N. R. |date=2020-11-25 |title=Extinction of herbivorous dinosaurs linked to Early Jurassic global warming event |url= |journal=Proceedings of the Royal Society B: Biological Sciences |language=en |volume=287 |issue=1939 |article-number=20202310 |doi=10.1098/rspb.2020.2310 |issn=0962-8452 |pmc=7739499 |pmid=33203331}}</ref> Some Jurassic sauropods reached gigantic sizes, becoming the largest organisms to have ever lived on land.<ref>{{Cite journal |last1=Sander |first1=P. Martin |last2=Christian |first2=Andreas |last3=Clauss |first3=Marcus |last4=Fechner |first4=Regina |last5=Gee |first5=Carole T. |last6=Griebeler |first6=Eva-Maria |last7=Gunga |first7=Hanns-Christian |last8=Hummel |first8=Jürgen |last9=Mallison |first9=Heinrich |last10=Perry |first10=Steven F. |last11=Preuschoft |first11=Holger |date=February 2011 |title=Biology of the sauropod dinosaurs: the evolution of gigantism |journal=Biological Reviews |language=en |volume=86 |issue=1 |pages=117–155 |doi=10.1111/j.1469-185X.2010.00137.x |pmc=3045712 |pmid=21251189}}</ref>

[[Basal (phylogenetics)|Basal]] bipedal [[Sauropodomorpha|sauropodomorphs]], such as [[Massospondylidae|massospondylids]], continued to exist into the Early Jurassic, but became extinct by the beginning of the Middle Jurassic.<ref name="Pol-2020" /> Quadrupedal sauropomorphs appeared during the Late Triassic. The quadrupedal ''[[Ledumahadi]]'' from the earliest Jurassic of South Africa reached an estimated weight of 12 tons, far in excess of other known basal sauropodomorphs.<ref>{{Cite journal |last1=McPhee |first1=Blair W. |last2=Benson |first2=Roger B.J. |last3=Botha-Brink |first3=Jennifer |last4=Bordy |first4=Emese M. |last5=Choiniere |first5=Jonah N. |date=8 October 2018 |title=A Giant Dinosaur from the Earliest Jurassic of South Africa and the Transition to Quadrupedality in Early Sauropodomorphs |journal=Current Biology |language=en |volume=28 |issue=19 |pages=3143–3151.e7 |bibcode=2018CBio...28E3143M |doi=10.1016/j.cub.2018.07.063 |pmid=30270189 |s2cid=52890502 |doi-access=free}}</ref> [[Gravisauria]]n sauropods first appeared during the Early Jurassic, with the oldest definitive record being ''[[Vulcanodon]]'' from Zimbabwe, likely of Sinemurian age.<ref>{{Cite journal |last1=Viglietti |first1=Pia A. |last2=Barrett |first2=Paul M. |last3=Broderick |first3=Tim J. |last4=Munyikwa |first4=Darlington |last5=MacNiven |first5=Rowan |last6=Broderick |first6=Lucy |last7=Chapelle |first7=Kimberley |last8=Glynn |first8=Dave |last9=Edwards |first9=Steve |last10=Zondo |first10=Michel |last11=Broderick |first11=Patricia |date=January 2018 |title=Stratigraphy of the Vulcanodon type locality and its implications for regional correlations within the Karoo Supergroup |url=https://linkinghub.elsevier.com/retrieve/pii/S1464343X17303953 |journal=Journal of African Earth Sciences |language=en |volume=137 |pages=149–156 |bibcode=2018JAfES.137..149V |doi=10.1016/j.jafrearsci.2017.10.015|url-access=subscription }}</ref> [[Eusauropoda|Eusauropods]] first appeared during the late Early Jurassic (Toarcian) and diversified during the Middle Jurassic;<ref name="Pol-2020" /> these included [[Cetiosauridae|cetiosaurids]], [[Turiasauria|turiasaurs]],<ref>{{Cite journal |last1=Royo-Torres |first1=Rafael |last2=Cobos |first2=Alberto |last3=Mocho |first3=Pedro |last4=Alcalá |first4=Luis |date=2021-01-01 |title=Origin and evolution of turiasaur dinosaurs set by means of a new 'rosetta' specimen from Spain |url=https://academic.oup.com/zoolinnean/article/191/1/201/5900936 |journal=Zoological Journal of the Linnean Society |language=en |volume=191 |issue=1 |pages=201–227 |doi=10.1093/zoolinnean/zlaa091 |issn=0024-4082 |doi-access=free}}</ref> and [[Mamenchisauridae|mamenchisaurs]].<ref>{{Cite journal |last1=Ren |first1=Xin-Xin |last2=Huang |first2=Jian-Dong |last3=You |first3=Hai-Lu |date=2020-05-27 |title=The second mamenchisaurid dinosaur from the Middle Jurassic of Eastern China |url=https://www.tandfonline.com/doi/full/10.1080/08912963.2018.1515935 |journal=Historical Biology |language=en |volume=32 |issue=5 |pages=602–610 |bibcode=2020HBio...32..602R |doi=10.1080/08912963.2018.1515935 |issn=0891-2963 |s2cid=91927243|url-access=subscription }}</ref> [[Neosauropoda|Neosauropods]] such as [[macronaria]]ns and [[Diplodocoidea|diplodocoids]] first appeared during the Middle Jurassic, before becoming abundant and globally distributed during the Late Jurassic.<ref>{{Cite journal |last1=Ren |first1=Xin-Xin |last2=Jiang |first2=Shan |last3=Wang |first3=Xu-Ri |last4=Peng |first4=Guang-Zhao |last5=Ye |first5=Yong |last6=Jia |first6=Lei |last7=You |first7=Hai-Lu |date=2022-11-14 |title=Re-examination of Dashanpusaurus dongi (Sauropoda: Macronaria) supports an early Middle Jurassic global distribution of neosauropod dinosaurs |url=https://www.sciencedirect.com/science/article/pii/S0031018222004898 |journal=Palaeogeography, Palaeoclimatology, Palaeoecology |language=en |volume=610 |article-number=111318 |doi=10.1016/j.palaeo.2022.111318 |issn=0031-0182|url-access=subscription }}</ref>

=== Other reptiles ===

==== Crocodylomorphs ====
[[File:Platysuchus multiscrobiculatus 1.JPG|thumb|[[Holotype]] specimen of ''[[Platysuchus]],'' a [[Teleosauridae|telosaurid]] [[thalattosuchia]]n]]
The Triassic–Jurassic extinction decimated [[pseudosuchia]]n diversity, with [[Crocodylomorpha|crocodylomorphs]], which originated during the early Late Triassic, being the only group of pseudosuchians to survive. All other pseudosuchians, including the herbivorous [[aetosaur]]s and carnivorous "[[rauisuchians]]", became extinct.<ref>{{Cite journal|last1=Allen|first1=Bethany J.|last2=Stubbs|first2=Thomas L.|last3=Benton|first3=Michael J.|last4=Puttick|first4=Mark N.|date=March 2019|editor-last=Mannion|editor-first=Philip|title=Archosauromorph extinction selectivity during the Triassic-Jurassic mass extinction|journal=Palaeontology|language=en|volume=62|issue=2|pages=211–224|doi=10.1111/pala.12399|bibcode=2019Palgy..62..211A |s2cid=55009185|doi-access=free|hdl=1983/e3fc2e40-c849-42ed-99fe-ea17fc26b2ec|hdl-access=free}}</ref> The morphological diversity of crocodylomorphs during the Early Jurassic was around the same as that of Late Triassic pseudosuchians, but they occupied different areas of morphospace, suggesting that they occupied different [[ecological niche]]s to their Triassic counterparts and that there was an extensive and rapid radiation of crocodylomorphs during this interval.<ref>{{Cite journal|last1=Toljagić|first1=Olja|last2=Butler|first2=Richard J.|date=2013-06-23|title=Triassic–Jurassic mass extinction as trigger for the Mesozoic radiation of crocodylomorphs|url= |journal=Biology Letters|language=en|volume=9|issue=3|article-number=20130095|doi=10.1098/rsbl.2013.0095|issn=1744-9561|pmc=3645043|pmid=23536443}}</ref> While living [[crocodilia]]ns are mostly confined to an aquatic ambush predator lifestyle, Jurassic crocodylomorphs exhibited a wide variety of life habits. An unnamed [[Protosuchidae|protosuchid]] known from teeth from the Early Jurassic of Arizona represents the earliest known herbivorous crocodylomorph, an adaptation that appeared several times during the Mesozoic.<ref>{{Cite journal|last1=Melstrom|first1=Keegan M.|last2=Irmis|first2=Randall B.|date=July 2019|title=Repeated Evolution of Herbivorous Crocodyliforms during the Age of Dinosaurs|journal=Current Biology|language=en|volume=29|issue=14|pages=2389–2395.e3|doi=10.1016/j.cub.2019.05.076|pmid=31257139|s2cid=195699188|doi-access=free|bibcode=2019CBio...29E2389M }}</ref>

The [[Thalattosuchia]], a clade of predominantly marine crocodylomorphs, first appeared during the Early Jurassic and became a prominent part of marine ecosystems.<ref name="Stubbs-2021">{{Cite journal|last1=Stubbs|first1=Thomas L.|last2=Pierce|first2=Stephanie E.|last3=Elsler|first3=Armin|last4=Anderson|first4=Philip S. L.|last5=Rayfield|first5=Emily J.|last6=Benton|first6=Michael J.|date=2021-03-31|title=Ecological opportunity and the rise and fall of crocodylomorph evolutionary innovation|journal=Proceedings of the Royal Society B: Biological Sciences|volume=288|issue=1947|article-number=20210069|doi=10.1098/rspb.2021.0069|pmid=33757349|pmc=8059953|s2cid=232326789}}</ref> Within Thalattosuchia, the [[Metriorhynchidae]] became highly adapted for life in the open ocean, including the transformation of limbs into flippers, the development of a tail fluke, and smooth, scaleless skin.<ref>{{Cite journal|last1=Spindler|first1=Frederik|last2=Lauer|first2=René|last3=Tischlinger|first3=Helmut|last4=Mäuser|first4=Matthias|date=2021-07-05|title=The integument of pelagic crocodylomorphs (Thalattosuchia: Metriorhynchidae)|url=https://palaeo-electronica.org/content/2021/3399-metriorhynchid-skin|journal=Palaeontologia Electronica|language=English|volume=24|issue=2|pages=1–41|doi=10.26879/1099|issn=1094-8074|doi-access=free}}</ref> The morphological diversity of crocodylomorphs during the Early and Middle Jurassic was relatively low compared to that in later time periods and was dominated by terrestrial small-bodied, long-legged [[sphenosuchia]]ns, early [[crocodyliformes|crocodyliforms]] and thalattosuchians.<ref>{{Cite journal|last1=Irmis|first1=Randall B.|last2=Nesbitt|first2=Sterling J.|last3=Sues|first3=Hans-Dieter|date=2013|title=Early Crocodylomorpha|url=http://sp.lyellcollection.org/lookup/doi/10.1144/SP379.24|journal=Geological Society, London, Special Publications|language=en|volume=379|issue=1|pages=275–302|bibcode=2013GSLSP.379..275I|doi=10.1144/SP379.24|issn=0305-8719|s2cid=219190410|url-access=subscription}}</ref><ref name="Stubbs-2021" /> The [[Neosuchia]], a major group of crocodylomorphs, first appeared during the Early to Middle Jurassic. The Neosuchia represents the transition from an ancestrally terrestrial lifestyle to a freshwater aquatic ecology similar to that occupied by modern crocodilians.<ref name="Wilberg-2019">{{Cite journal|last1=Wilberg|first1=Eric W.|last2=Turner|first2=Alan H.|last3=Brochu|first3=Christopher A.|date=2019-01-24|title=Evolutionary structure and timing of major habitat shifts in Crocodylomorpha|url= |journal=Scientific Reports|language=en|volume=9|issue=1|page=514|doi=10.1038/s41598-018-36795-1|pmid=30679529|pmc=6346023|bibcode=2019NatSR...9..514W|issn=2045-2322}}</ref> The timing of the origin of Neosuchia is disputed. The oldest record of Neosuchians has been suggested to be ''[[Calsoyasuchus]],'' from the Early Jurassic of Arizona, which in many analyses has been recovered as the earliest branching member of the neosuchian family [[Goniopholididae]], which radically alters times of diversification for crocodylomorphs. However, this placement has been disputed, with some analyses finding it outside Neosuchia, which would place the oldest records of Neosuchia in the Middle Jurassic.<ref name="Wilberg-2019" /> ''[[Razanandrongobe]]'' from the Middle Jurassic of Madagascar has been suggested to represent the oldest record of [[Notosuchia]], a primarily Gondwanan clade of mostly terrestrial crocodylomorphs, otherwise known from the Cretaceous and Cenozoic.<ref name="dalsasso2017">{{cite journal|last1=Dal Sasso|first1=C.|last2=Pasini|first2=G.|last3=Fleury|first3=G.|last4=Maganuco|first4=S.|year=2017|title=''Razanandrongobe sakalavae'', a gigantic mesoeucrocodylian from the Middle Jurassic of Madagascar, is the oldest known notosuchian|journal=PeerJ|volume=5|article-number=e3481|doi=10.7717/peerj.3481|pmc=5499610|pmid=28690926 |doi-access=free }}</ref>

==== Turtles ====
[[File:Thalassemys bruntrutana.jpg|thumb|''[[Thalassemys]],'' a [[thalassochelydia]]n sea turtle known from the Late Jurassic of Germany ]]
[[Stem-group]] turtles ([[Testudinata]]) diversified during the Jurassic. Jurassic stem-turtles belong to two progressively more advanced clades, the [[Mesochelydia]] and [[Perichelydia]].<ref name="Joyce-2017">{{Cite journal|last=Joyce|first=Walter G.|date=April 2017|title=A Review of the Fossil Record of Basal Mesozoic Turtles|journal=Bulletin of the Peabody Museum of Natural History|language=en|volume=58|issue=1|pages=65–113|doi=10.3374/014.058.0105|bibcode=2017BPMNH..58...65J |s2cid=54982901|issn=0079-032X|url=http://doc.rero.ch/record/288659/files/joy_rfm.pdf }}</ref> It is thought that the ancestral condition for mesochelydians is aquatic, as opposed to terrestrial for testudinates.<ref>{{Cite journal|last1=Sterli|first1=Juliana|last2=de la Fuente|first2=Marcelo S.|last3=Rougier|first3=Guillermo W.|date=2018-07-04|title=New remains of Condorchelys antiqua (Testudinata) from the Early-Middle Jurassic of Patagonia: anatomy, phylogeny, and paedomorphosis in the early evolution of turtles|url=https://www.tandfonline.com/doi/full/10.1080/02724634.2018.1480112|journal=Journal of Vertebrate Paleontology|language=en|volume=38|issue=4|pages=(1)–(17)|doi=10.1080/02724634.2018.1480112|bibcode=2018JVPal..38....1S |s2cid=109556104|issn=0272-4634|hdl=11336/99525|hdl-access=free}}</ref> The two modern groups of turtles ([[Turtle|Testudines]]), [[Pleurodira]] and [[Cryptodira]], diverged by the beginning of the Late Jurassic.<ref name="Joyce-2017" /> The oldest known pleurodires, the [[Platychelyidae]], are known from the Late Jurassic of Europe and the Americas,<ref>{{Cite journal|last1=Sullivan|first1=Patrick M.|last2=Joyce|first2=Walter G.|date=August 2017|title=The shell and pelvic anatomy of the Late Jurassic turtle Platychelys oberndorferi based on material from Solothurn, Switzerland|url=http://link.springer.com/10.1007/s13358-017-0136-7|journal=[[Swiss Journal of Palaeontology]]|language=en|volume=136|issue=2|pages=323–343|doi=10.1007/s13358-017-0136-7|bibcode=2017SwJP..136..323S |s2cid=90587841|issn=1664-2376|url-access=subscription}}</ref> while the oldest unambiguous cryptodire, ''[[Sinaspideretes]],'' an early relative of [[Trionychidae|softshell turtles]], is known from the Late Jurassic of China.<ref>{{Cite journal|last1=Evers|first1=Serjoscha W.|last2=Benson|first2=Roger B. J.|date=January 2019|editor-last=Smith|editor-first=Andrew|title=A new phylogenetic hypothesis of turtles with implications for the timing and number of evolutionary transitions to marine lifestyles in the group|url=https://onlinelibrary.wiley.com/doi/10.1111/pala.12384|journal=Palaeontology|language=en|volume=62|issue=1|pages=93–134|doi=10.1111/pala.12384|bibcode=2019Palgy..62...93E |s2cid=134736808}}</ref> The [[Thalassochelydia]], a diverse lineage of marine turtles unrelated to modern [[sea turtle]]s, are known from the Late Jurassic of Europe and South America.<ref>{{Cite journal|last1=Anquetin|first1=Jérémy|last2=Püntener|first2=Christian|last3=Joyce|first3=Walter G.|date=October 2017|title=A Review of the Fossil Record of Turtles of the Clade Thalassochelydia|url=http://www.bioone.org/doi/10.3374/014.058.0205|journal=Bulletin of the Peabody Museum of Natural History|language=en|volume=58|issue=2|pages=317–369|doi=10.3374/014.058.0205|bibcode=2017BPMNH..58..317A |s2cid=31091127|issn=0079-032X}}</ref>

==== Lepidosaurs ====
[[Rhynchocephalia]]ns (the sole living representative being the [[tuatara]]) had achieved a global distribution by the beginning of the Jurassic,<ref name="Evans-2010" /> and represented the dominant group of small reptiles during the Jurassic globally.<ref name=":20">{{Cite journal |last1=Brownstein |first1=Chase D. |last2=Meyer |first2=Dalton L. |last3=Fabbri |first3=Matteo |last4=Bhullar |first4=Bhart-Anjan S. |last5=Gauthier |first5=Jacques A. |date=2022-11-29 |title=Evolutionary origins of the prolonged extant squamate radiation |journal=Nature Communications |language=en |volume=13 |issue=1 |page=7087 |doi=10.1038/s41467-022-34217-5 |issn=2041-1723 |pmc=9708687 |pmid=36446761|bibcode=2022NatCo..13.7087B }}</ref> Rhynchocephalians reached their highest morphological diversity in their evolutionary history during the Jurassic, occupying a wide range of lifestyles, including the aquatic [[Pleurosauridae|pleurosaurs]] with long snake-like bodies and reduced limbs, the specialized herbivorous [[Eilenodontinae|eilenodontines]], as well as the [[sapheosaurs]] which had broad tooth plates indicative of [[durophagy]].<ref>{{Cite journal|last1=Herrera-Flores|first1=Jorge A.|last2=Stubbs|first2=Thomas L.|last3=Benton|first3=Michael J.|date=2017|title=Macroevolutionary patterns in Rhynchocephalia: is the tuatara (Sphenodon punctatus) a living fossil?|journal=Palaeontology|language=en|volume=60|issue=3|pages=319–328|doi=10.1111/pala.12284|bibcode=2017Palgy..60..319H |issn=1475-4983|doi-access=free}}</ref> Rhynchocephalians disappeared from Asia after the Early Jurassic.<ref name="Evans-2010">{{Citation|last1=Evans|first1=Susan E.|title=The Origin, Early History and Diversification of Lepidosauromorph Reptiles|date=2010|url=http://link.springer.com/10.1007/978-3-642-10311-7_2|work=New Aspects of Mesozoic Biodiversity|volume=132|pages=27–44|place=Berlin, Heidelberg|publisher=Springer Berlin Heidelberg|doi=10.1007/978-3-642-10311-7_2|isbn=978-3-642-10310-0|access-date=2021-01-07|last2=Jones|first2=Marc E.H.|series=Lecture Notes in Earth Sciences |bibcode=2010LNES..132...27E|url-access=subscription}}</ref> The last common ancestor of living [[Squamata|squamates]] (which includes [[lizard]]s and [[snake]]s) is estimated to have lived around 190 million years ago during the Early Jurassic, with the major divergences between modern squamate lineages estimated to have occurred during the Early to Middle Jurassic.<ref>{{Cite journal|last1=Burbrink|first1=Frank T|last2=Grazziotin|first2=Felipe G|last3=Pyron|first3=R Alexander|last4=Cundall|first4=David|last5=Donnellan|first5=Steve|last6=Irish|first6=Frances|last7=Keogh|first7=J Scott|last8=Kraus|first8=Fred|last9=Murphy|first9=Robert W|last10=Noonan|first10=Brice|last11=Raxworthy|first11=Christopher J|date=2020-05-01|editor-last=Thomson|editor-first=Robert|title=Interrogating Genomic-Scale Data for Squamata (Lizards, Snakes, and Amphisbaenians) Shows no Support for Key Traditional Morphological Relationships|url=https://academic.oup.com/sysbio/article/69/3/502/5573126|journal=Systematic Biology|language=en|volume=69|issue=3|pages=502–520|doi=10.1093/sysbio/syz062|pmid=31550008|issn=1063-5157|url-access=subscription}}</ref> Squamates first appear in the fossil record during the Middle Jurassic<ref name="Cleary-2018">{{Cite journal|last1=Cleary|first1=Terri J.|last2=Benson|first2=Roger B. J.|last3=Evans|first3=Susan E.|last4=Barrett|first4=Paul M.|date=21 March 2018|title=Lepidosaurian diversity in the Mesozoic–Palaeogene: the potential roles of sampling biases and environmental drivers|url= |journal=Royal Society Open Science|volume=5|issue=3|article-number=171830|doi=10.1098/rsos.171830|pmc=5882712|pmid=29657788|bibcode=2018RSOS....571830C}}</ref> including members of modern clades such as [[Scincomorpha]],<ref>{{Cite journal|last=Evans|first=S. E.|date=1998|title=Crown group lizards (Reptilia, Squamata) from the Middle Jurassic of the British Isles|journal=Palaeontographica, Abteilung A |volume=250|issue=4–6 |pages=123–154|doi=10.1127/pala/250/1998/123 |bibcode=1998PalAA.250..123E |s2cid=246932992 }}</ref> though many Jurassic squamates have unclear relationships to living groups.<ref>{{Cite journal|last1=Dong|first1=Liping|last2=Wang|first2=Yuan|last3=Mou|first3=Lijie|last4=Zhang|first4=Guoze|last5=Evans|first5=Susan E.|date=2019-09-13|title=A new Jurassic lizard from China|journal=Geodiversitas|volume=41|issue=16|page=623|doi=10.5252/geodiversitas2019v41a16|s2cid=204256127|issn=1280-9659|doi-access=free|bibcode=2019Geodv..41..623D }}</ref> ''[[Eichstaettisaurus]]'' from the Late Jurassic of Germany has been suggested to be an early relative of [[gecko]]s and displays adaptations for climbing.<ref>{{Cite journal|last1=Simões|first1=Tiago R.|last2=Caldwell|first2=Michael W.|last3=Nydam|first3=Randall L.|last4=Jiménez-Huidobro|first4=Paulina|date=September 2016|title=Osteology, phylogeny, and functional morphology of two Jurassic lizard species and the early evolution of scansoriality in geckoes |journal=Zoological Journal of the Linnean Society|language=en|doi=10.1111/zoj.12487}}</ref> ''[[Dorsetisaurus]]'' from the Late Jurassic of North America and Europe represents the oldest widely accepted record of [[Anguimorpha]].<ref>{{Cite journal|last1=Daza|first1=J. D.|last2=Bauer|first2=A. M.|last3=Stanley|first3=E. L.|last4=Bolet|first4=A.|last5=Dickson|first5=B.|last6=Losos|first6=J. B.|date=2018-11-01|title=An Enigmatic Miniaturized and Attenuate Whole Lizard from the Mid-Cretaceous Amber of Myanmar|url=https://bioone.org/journals/breviora/volume-563/issue-1/MCZ49.1/An-Enigmatic-Miniaturized-and-Attenuate-Whole-Lizard-from-the-Mid/10.3099/MCZ49.1.full|journal=Breviora|volume=563|issue=1|page=1|doi=10.3099/MCZ49.1|hdl=1983/0955fcf4-a32a-4498-b920-1421dcea67de |s2cid=91589111|issn=0006-9698|hdl-access=free}}</ref> ''[[Marmoretta]]'' from the Middle Jurassic of Britain has been suggested to represent a late surviving [[Lepidosauromorpha|lepidosauromorph]] outside both Rhynchocephalia and Squamata, though some studies have recovered it as a stem-squamate.<ref name="Griffiths spp2.1400">{{Cite journal |last1=Griffiths |first1=Elizabeth F. |last2=Ford |first2=David P. |last3=Benson |first3=Roger B.J. |last4=Evans |first4=Susan E. |date=September 2021 |editor-last=Ruta |editor-first=Marcello |title=New information on the Jurassic lepidosauromorph Marmoretta oxoniensis |url=https://onlinelibrary.wiley.com/doi/10.1002/spp2.1400 |journal=Papers in Palaeontology |language=en |volume=7 |issue=4 |pages=2255–2278 |doi=10.1002/spp2.1400 |bibcode=2021PPal....7.2255G |issn=2056-2799 |s2cid=239140732|url-access=subscription }}</ref>

<gallery>
File:Vadasaurus herzogi holotype (fossil).jpg|''[[Vadasaurus|Vadasaurus herzogi]]'', a rynchocephalian from the Upper Jurassic [[Solnhofen Limestone]] of Germany
File:Homeosaurus maximiliani, lizard, Jurassic, Solnhofen Limestone, Eichstatt, Bavaria, Germany - Houston Museum of Natural Science - DSC01988.JPG|''[[Homoeosaurus|Homeosaurus maximiliani]]'', a rynchocephalian from the Solnhofen Limestone
File:Pleurosaurus 783534.jpg|''[[Pleurosaurus]],'', an aquatic rhynchocephalian from the Late Jurassic of Europe
File:Eichstaettisaurus schroederi.JPG|''[[Eichstaettisaurus|Eichstaettisaurus schroederi]],'', an extinct lizard from the Solnhofen Limestone 
</gallery>

==== Choristoderes ====
[[File:Coeruleodraco paratype.jpg|left|thumb|upright=0.6|Skeleton of ''[[Coeruleodraco]]'']]
The earliest known remains of [[Choristodera]], a group of freshwater aquatic reptiles with uncertain affinities to other reptile groups, are found in the Middle Jurassic. Only two genera of choristodere are known from the Jurassic. One is the small lizard-like ''[[Cteniogenys]]'', thought to be the most basal known choristodere; it is known from the Middle to Late Jurassic of Europe and Late Jurassic of North America, with similar remains also known from the upper Middle Jurassic of Kyrgyzstan and western Siberia.<ref>{{Cite journal |last1=Matsumoto |first1=R. |last2=Evans |first2=S. E. |date=2010 |title=Choristoderes and the freshwater assemblages of Laurasia |url=http://revistas.ucm.es/index.php/JIGE/article/view/JIGE1010220253A |journal=Journal of Iberian Geology |volume=36 |issue=2 |pages=253–274 |doi=10.5209/rev_JIGE.2010.v36.n2.11 |issn=1698-6180 |doi-access=free |bibcode=2010JIbG...36..253M}}</ref> The other is ''[[Coeruleodraco]]'' from the Late Jurassic of China, which is a more advanced choristodere, though still small and lizard-like in morphology.<ref>{{Cite journal |last1=Matsumoto |first1=Ryoko |last2=Dong |first2=Liping |last3=Wang |first3=Yuan |last4=Evans |first4=Susan E. |date=2019-06-18 |title=The first record of a nearly complete choristodere (Reptilia: Diapsida) from the Upper Jurassic of Hebei Province, People's Republic of China |url=https://www.tandfonline.com/doi/full/10.1080/14772019.2018.1494220 |journal=Journal of Systematic Palaeontology |language=en |volume=17 |issue=12 |pages=1031–1048 |doi=10.1080/14772019.2018.1494220 |bibcode=2019JSPal..17.1031M |s2cid=92421503 |issn=1477-2019}}</ref>

==== Ichthyosaurs ====
[[File:Ichthyosaurus communis in London.jpg|thumb|Fossil of ''[[Ichthyosaurus somersetensis]]'' at the [[Natural History Museum, London]]|alt=Skeleton of an icthyosaur in side view]]
[[Ichthyosauria|Ichthyosaur]]s suffered an [[evolutionary bottleneck]] during the end-Triassic extinction, with all non-[[neoichthyosauria]]ns becoming extinct. Ichthyosaurs reached their apex of species diversity during the Early Jurassic, with an array of morphologies including the huge [[apex predator]] ''[[Temnodontosaurus]]'' and swordfish-like ''[[Eurhinosaurus]],'' though Early Jurassic ichthyosaurs were significantly less morphologically diverse than their Triassic counterparts.<ref name="Thorne-2011">{{Cite journal|last1=Thorne|first1=P. M.|last2=Ruta|first2=M.|last3=Benton|first3=M. J.|date=2011-05-17|title=Resetting the evolution of marine reptiles at the Triassic-Jurassic boundary|journal=Proceedings of the National Academy of Sciences|language=en|volume=108|issue=20|pages=8339–8344|bibcode=2011PNAS..108.8339T|doi=10.1073/pnas.1018959108|issn=0027-8424|pmc=3100925|pmid=21536898|doi-access=free}}</ref><ref name="Moon-2020">{{Cite journal|last1=Moon|first1=Benjamin C.|last2=Stubbs|first2=Thomas L.|date=2020-02-13|title=Early high rates and disparity in the evolution of ichthyosaurs|url= |journal=Communications Biology|language=en|volume=3|issue=1|page=68|doi=10.1038/s42003-020-0779-6|pmid=32054967|pmc=7018711|issn=2399-3642}}</ref> At the Early–Middle Jurassic boundary, between the end of the Toarcian and the beginning of the Bajocian, most lineages of ichythosaur appear to have become extinct, with the first appearance of the [[Ophthalmosauridae]], the clade that would encompass almost all ichthyosaurs from then on, during the early Bajocian.<ref name="Fischer-2021">{{Cite journal|last1=Fischer|first1=Valentin|last2=Weis|first2=Robert|last3=Thuy|first3=Ben|date=2021-02-22|title=Refining the marine reptile turnover at the Early–Middle Jurassic transition|journal=PeerJ|language=en|volume=9|article-number=e10647|doi=10.7717/peerj.10647|pmid=33665003|pmc=7906043|issn=2167-8359 |doi-access=free }}</ref> Ophthalmosaurids were diverse by the Late Jurassic, but failed to fill many of the niches that had been occupied by ichthyosaurs during the Early Jurassic.<ref name="Fischer-2021" /><ref name="Thorne-2011" /><ref name="Moon-2020" />

==== Plesiosaurs ====
[[File:Rhomaleosaurus cramptoni (fossil).jpg|thumb|''[[Rhomaleosaurus|Rhomaleosaurus cramptoni]]'' at the Natural History Museum, London]]
[[Plesiosauria|Plesiosaurs]] originated at the end of the Triassic (Rhaetian). By the end of the Triassic, all other [[sauropterygia]]ns, including [[Placodontia|placodonts]] and [[nothosaur]]s, had become extinct. At least six lineages of plesiosaur crossed the Triassic–Jurassic boundary.<ref>{{Cite journal|last1=Wintrich|first1=Tanja|last2=Hayashi|first2=Shoji|last3=Houssaye|first3=Alexandra|last4=Nakajima|first4=Yasuhisa|last5=Sander|first5=P. Martin|date=2017-12-01|title=A Triassic plesiosaurian skeleton and bone histology inform on evolution of a unique body plan|url= |journal=Science Advances|language=en|volume=3|issue=12|article-number=e1701144|doi=10.1126/sciadv.1701144|pmid=29242826|pmc=5729018|bibcode=2017SciA....3E1144W|issn=2375-2548}}</ref> Plesiosaurs were already diverse in the earliest Jurassic, with the majority of plesiosaurs in the Hettangian-aged Blue Lias belonging to the [[Rhomaleosauridae]]. Early plesiosaurs were generally small-bodied, with body size increasing into the Toarcian.<ref>{{Cite journal|last1=Benson|first1=Roger B. J.|last2=Evans|first2=Mark|last3=Druckenmiller|first3=Patrick S.|date=2012-03-16|title=High Diversity, Low Disparity and Small Body Size in Plesiosaurs (Reptilia, Sauropterygia) from the Triassic–Jurassic Boundary|journal=PLOS ONE|language=en|volume=7|issue=3|article-number=e31838|doi=10.1371/journal.pone.0031838|issn=1932-6203|pmc=3306369|pmid=22438869|bibcode=2012PLoSO...731838B|doi-access=free}}</ref> There appears to have been a strong turnover around the Early–Middle Jurassic boundary, with [[Microcleididae|microcleidids]] and rhomaleosaurids becoming extinct and nearly extinct respectively after the end of the Toarcian with the first appearance of the dominant clade of plesiosaurs of the latter half of the Jurassic, the [[Cryptoclididae]] during the Bajocian.<ref name="Fischer-2021" /> The Middle Jurassic saw the evolution of short-necked and large-headed [[Thalassophonea|thalassophonean pliosaurs]] from ancestrally small-headed, long-necked forms''.''<ref>{{Cite journal|last=O'Keefe|first=F. Robin|date=2002|title=The evolution of plesiosaur and pliosaur morphotypes in the Plesiosauria (Reptilia: Sauropterygia)|url=https://www.cambridge.org/core/journals/paleobiology/article/abs/evolution-of-plesiosaur-and-pliosaur-morphotypes-in-the-plesiosauria-reptilia-sauropterygia/8A68F79F7BCF0D56D2D7435D3A018704|journal=Paleobiology|language=en|volume=28|issue=1|pages=101–112|doi=10.1666/0094-8373(2002)028<0101:TEOPAP>2.0.CO;2|bibcode=2002Pbio...28..101O |s2cid=85753943 |issn=0094-8373}}</ref><ref name="Fischer-2021" /> Some thalassophonean pliosaurs, such as some species of ''[[Pliosaurus]]'', had skulls up to two metres in length with body lengths estimated around {{convert|10|–|12|m|ft|sp=us}}, making them the apex predators of Late Jurassic oceans.<ref>{{Cite journal|last1=Benson|first1=Roger B. J.|last2=Evans|first2=Mark|last3=Smith|first3=Adam S.|last4=Sassoon|first4=Judyth|last5=Moore-Faye|first5=Scott|last6=Ketchum|first6=Hilary F.|last7=Forrest|first7=Richard|date=2013-05-31|title=A Giant Pliosaurid Skull from the Late Jurassic of England|journal=PLOS ONE|language=en|volume=8|issue=5|article-number=e65989|doi=10.1371/journal.pone.0065989|issn=1932-6203|pmc=3669260|pmid=23741520|bibcode=2013PLoSO...865989B|doi-access=free}}</ref><ref name="Fischer-2021" /> Plesiosaurs invaded freshwater environments during the Jurassic, with indeterminate remains of small-bodied pleisosaurs known from freshwater sediments from the Jurassic of China and Australia.<ref>{{Cite journal|last1=Gao|first1=Ting|last2=Li|first2=Da-Qing|last3=Li|first3=Long-Feng|last4=Yang|first4=Jing-Tao|date=2019-08-13|title=The first record of freshwater plesiosaurian from the Middle Jurassic of Gansu, NW China, with its implications to the local palaeobiogeography|journal=Journal of Palaeogeography|volume=8|issue=1|page=27|doi=10.1186/s42501-019-0043-5|bibcode=2019JPalG...8...27G|s2cid=199547716|issn=2524-4507|doi-access=free}}</ref><ref>{{Cite journal|last=Kear|first=Benjamin P.|date=2 August 2012|title=A revision of Australia's Jurassic plesiosaurs |journal=Palaeontology|language=en|volume=55|issue=5|pages=1125–1138|doi=10.1111/j.1475-4983.2012.01183.x|bibcode=2012Palgy..55.1125K |doi-access=free}}</ref>

==== Pterosaurs ====
[[File:Rhamphorhynchus Lauer.jpg|thumb|Skeleton of ''[[Rhamphorhynchus|Rhamphorhynchus muensteri]]'' at [[Teylers Museum]], [[Haarlem]]|left]]
[[Pterosaur]]s first appeared in the Late Triassic. A major radiation of Jurassic pterosaurs is the [[Rhamphorhynchidae]], which first appeared in the late Early Jurassic (Toarcian);<ref>{{Cite journal|last1=O'Sullivan|first1=Michael|last2=Martill|first2=David M.|date=2017-11-17|title=The taxonomy and systematics of Parapsicephalus purdoni (Reptilia: Pterosauria) from the Lower Jurassic Whitby Mudstone Formation, Whitby, U.K|url=https://www.tandfonline.com/doi/full/10.1080/08912963.2017.1281919|journal=Historical Biology|language=en|volume=29|issue=8|pages=1009–1018|doi=10.1080/08912963.2017.1281919|bibcode=2017HBio...29.1009O |s2cid=132532024|issn=0891-2963}}</ref> they are thought to been [[Piscivore|piscivorous]].<ref name="Bestwick-2018">{{Cite journal|last1=Bestwick|first1=Jordan|last2=Unwin|first2=David M.|last3=Butler|first3=Richard J.|last4=Henderson|first4=Donald M.|last5=Purnell|first5=Mark A.|date=November 2018|title=Pterosaur dietary hypotheses: a review of ideas and approaches: Pterosaur dietary hypotheses |journal=Biological Reviews|language=en|volume=93|issue=4|pages=2021–2048|doi=10.1111/brv.12431|pmc=6849529|pmid=29877021}}</ref> [[Anurognathidae|Anurognathids]], which first appeared in the Middle Jurassic, possessed short heads and densely furred bodies, and are thought to have been insectivores.<ref name="Bestwick-2018" /> Derived [[monofenestrata]]n pterosaurs such as [[Wukongopteridae|wukongopterids]] appeared in the late Middle Jurassic. Advanced short-tailed [[Pterodactyloidea|pterodactyloids]] first appeared at the Middle–Late Jurassic boundary. Jurassic pterodactyloids include the [[Ctenochasmatoidea|ctenochasmatids]], like ''[[Ctenochasma]]'', which have closely spaced needle-like teeth that were presumably used for [[Filter feeder|filter feeding]].<ref name="Bestwick-2018" /> The bizarre Late Jurassic [[Ctenochasmatoidea|ctenochasmatoid]] ''[[Cycnorhamphus]]'' had a jaw with teeth only at the tips, with bent jaws like those of living [[openbill stork]]s that may have been used to hold and crush hard invertebrates.<ref name="Bestwick-2018" />

=== Amphibians ===
[[File:Karaurus sharovi.JPG|thumb|upright|Skeleton of ''[[Karaurus|Karaurus sharovi]],'' a stem-group salamander from the Middle to Late Jurassic of Kazakhstan|alt=Topside view of a salamander skeleton]]
The diversity of [[Temnospondyli|temnospondyls]] had progressively declined through the Late Triassic, with only [[Brachyopoidea|brachyopoids]] surviving into the Jurassic and beyond.<ref>{{Citation|last=Lucas|first=Spencer G.|title=Late Triassic Terrestrial Tetrapods: Biostratigraphy, Biochronology and Biotic Events|date=2018|url=http://link.springer.com/10.1007/978-3-319-68009-5_10|work=The Late Triassic World|series=Topics in Geobiology|volume=46|pages=351–405|editor-last=Tanner|editor-first=Lawrence H.|place=Cham|publisher=Springer International Publishing |doi=10.1007/978-3-319-68009-5_10|isbn=978-3-319-68008-8|access-date=2021-04-25|url-access=subscription}}</ref> Members of the family [[Brachyopidae]] are known from Jurassic deposits in Asia,<ref>{{Cite journal|last1=Averianov|first1=Alexander O.|last2=Martin|first2=Thomas|last3=Skutschas|first3=Pavel P. |last4=Rezvyi|first4=Anton S.|last5=Bakirov|first5=Aizek A.|title=Amphibians from the Middle Jurassic Balabansai Svita in the Fergana Depression, Kyrgyzstan (Central Asia)|date=March 2008 |journal=Palaeontology|language=en|volume=51|issue=2|pages=471–485|doi=10.1111/j.1475-4983.2007.00748.x |bibcode=2008Palgy..51..471A |doi-access=free}}</ref> while the [[Chigutisauridae|chigutisaurid]] ''[[Siderops]]'' is known from the Early Jurassic of Australia.<ref>{{Cite journal|last1=Warren|first1=A. A.|last2=Hutchinson|first2=M. N.|last3=Hill|first3=Dorothy|date=1983-09-13|title=The last Labyrinthodont? A new brachyopoid (Amphibia, Temnospondyli) from the early Jurassic Evergreen formation of Queensland, Australia|url=https://royalsocietypublishing.org/doi/10.1098/rstb.1983.0080|journal=Philosophical Transactions of the Royal Society of London. B, Biological Sciences|volume=303|issue=1113|pages=1–62|doi=10.1098/rstb.1983.0080|bibcode=1983RSPTB.303....1W|url-access=subscription}}</ref> Modern [[lissamphibia]]ns began to diversify during the Jurassic. The Early Jurassic ''[[Prosalirus]]'' thought to represent the first frog relative with a morphology capable of hopping like living frogs.<ref>{{Cite journal|last1=Reilly|first1=Stephen M.|last2=Jorgensen|first2=Michael E.|date=February 2011 |title=The evolution of jumping in frogs: Morphological evidence for the basal anuran locomotor condition and the radiation of locomotor systems in crown group anurans |journal=Journal of Morphology|language=en|volume=272|issue=2|pages=149–168|doi=10.1002/jmor.10902 |pmid=21210487 |bibcode=2011JMorp.272..149R |s2cid=14217777}}</ref> Morphologically recognisable stem-frogs like the South American ''[[Notobatrachus]]'' are known from the Middle Jurassic,<ref>{{Cite journal|last1=Báez|first1=Ana Maria|last2=Nicoli|first2=Laura|date=March 2008|title=A new species of Notobatrachus (Amphibia, Salientia) from the Middle Jurassic of northwestern Patagonia|journal=Journal of Paleontology |volume=82|issue=2|pages=372–376|doi=10.1666/06-117.1|bibcode=2008JPal...82..372B |s2cid=130032431|issn=0022-3360|hdl=11336/135748|hdl-access=free}}</ref> with modern crown-group frogs like ''[[Enneabatrachus]]'' and ''[[Rhadinosteus]]'' appearing by the Late Jurassic.<ref>{{Cite journal |last1=Marjanović |first1=David |last2=Laurin |first2=Michel |date=2014-07-04 |title=An updated paleontological timetree of lissamphibians, with comments on the anatomy of Jurassic crown-group salamanders (Urodela) |url=http://www.tandfonline.com/doi/abs/10.1080/08912963.2013.797972 |journal=Historical Biology |language=en |volume=26 |issue=4 |pages=535–550 |doi=10.1080/08912963.2013.797972 |bibcode=2014HBio...26..535M |s2cid=84581331 |issn=0891-2963|url-access=subscription }}</ref> While the earliest salamander-line amphibians are known from the Triassic,<ref>{{Cite journal|last1=Schoch|first1=Rainer R. |last2=Werneburg|first2=Ralf|last3=Voigt|first3=Sebastian|date=2020-05-26|title=A Triassic stem-salamander from Kyrgyzstan and the origin of salamanders|journal=Proceedings of the National Academy of Sciences|language=en|volume=117|issue=21|pages=11584–11588|doi=10.1073/pnas.2001424117 |issn=0027-8424|pmc=7261083|pmid=32393623|bibcode=2020PNAS..11711584S |doi-access=free}}</ref> [[crown group]] salamanders first appear during the Middle to Late Jurassic in Eurasia, alongside stem-group relatives. Many Jurassic stem-group salamanders, such as ''[[Marmorerpeton]]'' and ''[[Kokartus]]'', are thought to have been [[Neoteny|neotenic]].<ref>{{Cite journal|last1=Skutschas|first1=Pavel|last2=Stein|first2=Koen |date=April 2015|title=Long bone histology of the stem salamander Kokartus honorarius (Amphibia: Caudata) from the Middle Jurassic of Kyrgyzstan |journal=Journal of Anatomy|language=en|volume=226|issue=4|pages=334–347|doi=10.1111/joa.12281|pmc=4386933|pmid=25682890}}</ref> Early representatives of crown group salamanders include ''[[Chunerpeton]], [[Pangerpeton]]'' and ''[[Linglongtriton]]'' from the Middle to Late Jurassic [[Yanliao Biota]] of China. Some of these are suggested to belong to [[Cryptobranchoidea]], which contains living [[Asiatic salamander|Asiatic]] and [[giant salamander]]s.<ref>{{Cite journal|last1=Jia|first1=Jia|last2=Gao|first2=Ke-Qin|date=2019-03-04|title=A new stem hynobiid salamander (Urodela, Cryptobranchoidea) from the Upper Jurassic (Oxfordian) of Liaoning Province, China |url=https://www.tandfonline.com/doi/full/10.1080/02724634.2019.1588285|journal=Journal of Vertebrate Paleontology|language=en|volume=39|issue=2|article-number=e1588285|doi=10.1080/02724634.2019.1588285|bibcode=2019JVPal..39E8285J |s2cid=164310171|issn=0272-4634|url-access=subscription}}</ref> ''[[Beiyanerpeton]]'', and ''[[Qinglongtriton]]'' from the same biota are thought to be early members of [[Salamandroidea]], the group which contains all other living salamanders.<ref>{{Cite journal|last1=Gao|first1=K.-Q.|last2=Shubin|first2=N. H. |date=2012-04-10|title=Late Jurassic salamandroid from western Liaoning, China|journal=Proceedings of the National Academy of Sciences |language=en|volume=109|issue=15|pages=5767–5772|doi=10.1073/pnas.1009828109|issn=0027-8424|pmc=3326464|pmid=22411790|bibcode=2012PNAS..109.5767G |doi-access=free}}</ref><ref>{{Cite journal|last1=Jia|first1=Jia|last2=Gao|first2=Ke-Qin|date=2016-05-04|title=A New Basal Salamandroid (Amphibia, Urodela) from the Late Jurassic of Qinglong, Hebei Province, China|journal=PLOS ONE|language=en|volume=11|issue=5|article-number=e0153834 |doi=10.1371/journal.pone.0153834|issn=1932-6203|pmc=4856324|pmid=27144770|bibcode=2016PLoSO..1153834J|doi-access=free}}</ref> Salamanders dispersed into North America by the end of the Jurassic, as evidenced by ''[[Iridotriton]]'', found in the Late Jurassic [[Morrison Formation]].<ref>{{cite journal|last1=Evans|first1=S. E.|last2=Lally|first2=C.|last3=Chure|first3=D. C.|last4=Elder|first4=A.|last5=Maisano|first5=J. A. |year=2005 |title=A Late Jurassic salamander (Amphibia: Caudata) from the Morrison Formation of North America|journal=Zoological Journal of the Linnean Society |volume=143 |issue=4 |pages=599–616 |doi=10.1111/j.1096-3642.2005.00159.x|doi-access=free}}</ref> The stem-[[caecilian]] ''[[Eocaecilia]]'' is known from the Early Jurassic of Arizona.<ref>{{Cite journal|last1=Santos|first1=Rodolfo Otávio|last2=Laurin|first2=Michel |last3=Zaher|first3=Hussam|date=2020-11-03|title=A review of the fossil record of caecilians (Lissamphibia: Gymnophionomorpha) with comments on its use to calibrate molecular timetrees|journal=Biological Journal of the Linnean Society|volume=131|issue=4|language=en|pages=737–755 |doi=10.1093/biolinnean/blaa148|issn=0024-4066|doi-access=free}}</ref> The fourth group of lissamphibians, the extinct salamander-like [[Albanerpetontidae|albanerpetontids]], first appeared in the Middle Jurassic, represented by ''[[Anoualerpeton|Anoualerpeton priscus]]'' from the Bathonian of Britain, as well as indeterminate remains from equivalently aged sediments in France and the [[Anoual Formation]] of Morocco.<ref>{{Cite journal|last1=Haddoumi|first1=Hamid|last2=Allain|first2=Ronan|last3=Meslouh|first3=Said|last4=Metais|first4=Grégoire|last5=Monbaron |first5=Michel|last6=Pons|first6=Denise|last7=Rage|first7=Jean-Claude|last8=Vullo|first8=Romain|last9=Zouhri|first9=Samir|date=January 2016 |title=Guelb el Ahmar (Bathonian, Anoual Syncline, eastern Morocco): First continental flora and fauna including mammals from the Middle Jurassic of Africa|url=http://doc.rero.ch/record/258861/files/mon_gab.pdf|journal=Gondwana Research|volume=29|issue=1|pages=290–319 |doi=10.1016/j.gr.2014.12.004|bibcode=2016GondR..29..290H|issn=1342-937X}}</ref>[[File:Henkeloth.jpg|left|thumb|''[[Henkelotherium]],'' a likely arboreal dyolestoid from the Late Jurassic of Portugal]]

=== Mammaliaformes ===
[[Mammaliaformes]], including [[mammal]]s, having originated from [[cynodont]]s at the end of the Triassic, diversified extensively during the Jurassic.<ref name="Lee-2015" /> While most Jurassic mammalaliaforms are solely known from isolated teeth and jaw fragments, exceptionally preserved remains have revealed a variety of lifestyles.<ref name="Lee-2015">{{Cite journal|last1=Lee|first1=Michael S.Y.|last2=Beck|first2=Robin M.D.|date=31 August 2015|title=Mammalian Evolution: A Jurassic Spark|journal=Current Biology|language=en|volume=25|issue=17|pages=R759–R761 |doi=10.1016/j.cub.2015.07.008|pmid=26325137|s2cid=11088107|doi-access=free|bibcode=2015CBio...25.R759L }}</ref> The [[docodonta]]n ''[[Castorocauda]]'' was adapted to aquatic life, similarly to the [[platypus]] and [[otter]]s.<ref name="Ji2006">{{cite journal|last1=Ji |first1=Q.|last2=Luo|first2=Z.-X.|last3=Yuan|first3=C.-X.|last4=Tabrum|first4=A. R.|year=2006|title=A swimming mammaliaform from the Middle Jurassic and ecomorphological diversification of early mammals|journal=Science|volume=311|issue=5,764|pages=1,123–1,127 |bibcode=2006Sci...311.1123J |doi=10.1126/science.1123026|pmid=16497926|s2cid=46067702|url=http://doc.rero.ch/record/13437/files/PAL_E249.pdf}}</ref> Some members of [[Haramiyida]]<ref>{{Cite journal|last1=Meng|first1=Qing-Jin|last2=Grossnickle|first2=David M.|last3=Liu|first3=Di |last4=Zhang|first4=Yu-Guang|last5=Neander|first5=April I.|last6=Ji|first6=Qiang|last7=Luo|first7=Zhe-Xi|date=August 2017|title=New gliding mammaliaforms from the Jurassic|url=https://www.nature.com/articles/nature23476|journal=Nature|language=en|volume=548|issue=7667|pages=291–296 |doi=10.1038/nature23476|pmid=28792929|bibcode=2017Natur.548..291M|s2cid=205259206|issn=1476-4687|url-access=subscription}}</ref> and the [[eutriconodonta]]n tribe [[Volaticotherini]]<ref name="desc">Meng, J.; Hu, Y.-M.; Wang, Y.-Q.; Wang, X.-L.; Li, C.-K. (2007). "Corrigendum: A Mesozoic gliding mammal from northeastern China". Nature 446 (7131): 102. {{Bibcode|2007Natur.446Q.102M}}. {{doi|10.1038/nature05639}}.</ref> had a [[patagium]] akin to those of [[flying squirrel]]s, allowing them to glide through the air. The [[aardvark]]-like mammal ''[[Fruitafossor]]'', of uncertain taxonomy, was likely a specialist on colonial insects, similarly to living [[anteater]]s.<ref name="Luo2005">{{cite journal|last1=Luo|first1=Z.-X.|last2=Wible |first2=J.R.|year=2005|title=A Late Jurassic Digging Mammal and Early Mammalian Diversification|journal=Science|volume=308|issue=5718|pages=103–107|bibcode=2005Sci...308..103L|doi=10.1126/science.1108875|issn=0036-8075|pmid=15802602|s2cid=7031381}}</ref> [[Australosphenida]], a group of mammals possibly related to living [[monotreme]]s, first appeared in the Middle Jurassic of Gondwana.<ref>{{Cite journal|last1=Luo|first1=Zhe-Xi |last2=Cifelli|first2=Richard L.|last3=Kielan-Jaworowska|first3=Zofia|date=January 2001|title=Dual origin of tribosphenic mammals |url=http://www.nature.com/articles/35051023|journal=Nature|language=en|volume=409|issue=6816|pages=53–57|doi=10.1038/35051023|pmid=11343108 |bibcode=2001Natur.409...53L|s2cid=4342585|issn=0028-0836|via=|url-access=subscription}}</ref> The earliest records of [[Multituberculata|multituberculates]], one of the longest lasting and most successful orders of mammals, are known from the Middle Jurassic.<ref>{{Cite journal |last1=Mao |first1=Fangyuan |last2=Brewer |first2=Philippa |last3=Hooker |first3=Jerry J. |last4=Meng |first4=Jin |date=2022-12-31 |title=New allotherian specimens from the Middle Jurassic Woodeaton Quarry (Oxfordshire) and implications for haramiyidan diversity and phylogeny |url=https://www.tandfonline.com/doi/full/10.1080/14772019.2022.2097021 |journal=Journal of Systematic Palaeontology |language=en |volume=20 |issue=1 |pages=1–37 |doi=10.1080/14772019.2022.2097021 |issn=1477-2019|url-access=subscription }}</ref> [[Theria]]n mammals, represented today by living [[Placentalia|placentals]] and [[marsupial]]s, diversified meteorically during the Middle Jurassic.<ref>{{Cite journal |last1=Close |first1=Roger A. |last2=Friedman |first2=Matt |last3=Lloyd |first3=Graeme T. |last4=Benson |first4=Roger B. J. |date=17 August 2015 |title=Evidence for a Mid-Jurassic Adaptive Radiation in Mammals |url=https://www.sciencedirect.com/science/article/pii/S0960982215007411 |journal=[[Current Biology]] |language=en |volume=25 |issue=16 |pages=2137–2142 |doi=10.1016/j.cub.2015.06.047 |pmid=26190074 |bibcode=2015CBio...25.2137C |access-date=4 November 2024 |via=Elsevier Science Direct}}</ref> They have their earliest records during the early Late Jurassic, represented by ''[[Juramaia]],'' a [[eutheria]]n mammal closer to the ancestry of placentals than marsupials.<ref name="Juramaia">{{cite journal|author=Zhe-Xi Luo|author2=Chong-Xi Yuan|author3=Qing-Jin Meng|author4=Qiang Ji|date=25 August 2011|title=A Jurassic eutherian mammal and divergence of marsupials and placentals |url=http://211.144.68.84:9998/91keshi/Public/File/34/476-7361/pdf/nature10291.pdf|journal=Nature |volume=476 |issue=7361 |pages=442–445 |doi=10.1038/nature10291 |pmid=21866158 |bibcode=2011Natur.476..442L |s2cid=205225806 |archive-url=https://web.archive.org/web/20131110134026/http://211.144.68.84:9998/91keshi/Public/File/34/476-7361/pdf/nature10291.pdf|archive-date=10 November 2013}} [http://www.nature.com/nature/journal/v476/n7361/extref/nature10291-s1.pdf Electronic supplementary material]</ref> ''Juramaia'' is much more advanced than expected for its age, as other therian mammals are not known until the Early Cretaceous, and it has been suggested that ''Juramaia'' may also originate from the Early Cretaceous instead.<ref>{{Cite journal|last1=King|first1=Benedict|last2=Beck|first2=Robin M. D.|date=2020-06-10|title=Tip dating supports novel resolutions of controversial relationships among early mammals|url= |journal=Proceedings of the Royal Society B: Biological Sciences|volume=287|issue=1928|article-number=20200943|doi=10.1098/rspb.2020.0943|pmc=7341916|pmid=32517606}}</ref> Two groups of non-mammaliaform cynodonts persisted beyond the end of the Triassic. The insectiviorous [[Tritheledontidae]] has a few records from the Early Jurassic. The [[Tritylodontidae]], a herbiviorous group of cynodonts that first appeared during the Rhaetian, has abundant records from the Jurassic, overwhelmingly from the Northern Hemisphere.<ref>{{Cite journal|last1=Ruta|first1=Marcello|last2=Botha-Brink|first2=Jennifer |last3=Mitchell|first3=Stephen A.|last4=Benton|first4=Michael J.|date=2013-10-22|title=The radiation of cynodonts and the ground plan of mammalian morphological diversity|url= |journal=Proceedings of the Royal Society B: Biological Sciences|language=en|volume=280|issue=1769 |article-number=20131865|doi=10.1098/rspb.2013.1865|issn=0962-8452|pmc=3768321|pmid=23986112}}</ref><ref>{{Citation|last1=Abdala|first1=Fernando|title=The Late Triassic Record of Cynodonts: Time of Innovations in the Mammalian Lineage|date=2018|url=http://link.springer.com/10.1007/978-3-319-68009-5_11|work=The Late Triassic World|volume=46|pages=407–445|editor-last=Tanner|editor-first=Lawrence H.|place=Cham|publisher=Springer International Publishing|language=en|doi=10.1007/978-3-319-68009-5_11|isbn=978-3-319-68008-8|access-date=2021-05-24|last2=Gaetano|first2=Leandro C. |series=Topics in Geobiology |url-access=subscription}}</ref>

=== Fish ===

==== Jawless fish ====
[[File:Yanliaomyzon.png|thumb|Fossils and life restorations of the two species of ''[[Yanliaomyzon]] ,'' a [[lamprey]] known from the Middle Jurassic of China]]
The last known species of [[conodont]], a class of [[Agnatha|jawless fish]] whose hard, tooth-like elements are key index fossils, finally became extinct during the earliest Jurassic after over 300 million years of evolutionary history, with an asynchronous extinction occurring first in the Tethys and eastern Panthalassa and survivors persisting into the earliest Hettangian of Hungary and central Panthalassa.<ref>{{Cite journal |last1=Du|first1=Yixing|last2=Chiari|first2=Marco|last3=Karádi|first3=Viktor|last4=Nicora|first4=Alda|last5=Onoue|first5=Tetsuji|last6=Pálfy |first6=József|last7=Roghi|first7=Guido|last8=Tomimatsu|first8=Yuki|last9=Rigo|first9=Manuel|date=April 2020|title=The asynchronous disappearance of conodonts: New constraints from Triassic-Jurassic boundary sections in the Tethys and Panthalassa |url=https://linkinghub.elsevier.com/retrieve/pii/S0012825220302221|journal=Earth-Science Reviews|language=en|volume=203|article-number=103176 |doi=10.1016/j.earscirev.2020.103176|bibcode=2020ESRv..20303176D|hdl=11577/3338908 |s2cid=216173452|url-access=subscription}}</ref> End-Triassic conodonts were represented by only a handful of species and had been progressively declining through the Middle and Late Triassic.<ref>{{Cite journal |last1=Ginot|first1=Samuel|last2=Goudemand|first2=Nicolas|date=December 2020|title=Global climate changes account for the main trends of conodont diversity but not for their final demise|url=https://linkinghub.elsevier.com/retrieve/pii/S0921818120302162|journal=Global and Planetary Change |language=en|volume=195|article-number=103325|doi=10.1016/j.gloplacha.2020.103325|bibcode=2020GPC...19503325G|s2cid=225005180}}</ref> ''[[Yanliaomyzon]]'' from the Middle Jurassic of China represents the oldest post Paleozoic [[lamprey]], and the oldest lamprey to have the toothed feeding apparatus and likely the three stage life cycle typical of modern members of the group.<ref name="Wu-2023">{{Cite journal |last1=Wu |first1=Feixiang |last2=Janvier |first2=Philippe |last3=Zhang |first3=Chi |date=2023-10-31 |title=The rise of predation in Jurassic lampreys |journal=Nature Communications |language=en |volume=14 |issue=1 |page=6652 |doi=10.1038/s41467-023-42251-0 |issn=2041-1723|doi-access=free |pmid=37907522 |pmc=10618186 |bibcode=2023NatCo..14.6652W }}</ref>

==== Sarcopterygii ====
[[File:Coelacanth, Late Late Jurassic, Tithonian Age, Solnhofen Lithographic Limestone, Solnhofen, Bavaria, Germany - Houston Museum of Natural Science - DSC01858.JPG|thumb|Coelacanth from the Solnhofen Limestone|left]]
[[Lungfish]] (Dipnoi) were present in freshwater environments of both hemispheres during the Jurassic.<ref>{{Cite journal|last1=Kemp|first1=Anne |last2=Cavin|first2=Lionel|last3=Guinot|first3=Guillaume|date=April 2017|title=Evolutionary history of lungfishes with a new phylogeny of post-Devonian genera|journal=Palaeogeography, Palaeoclimatology, Palaeoecology|language=en|volume=471|pages=209–219|doi=10.1016/j.palaeo.2016.12.051 |bibcode=2017PPP...471..209K|doi-access=free}}</ref> Some studies have proposed that the last common ancestor of all living lungfish lived during the Jurassic.<ref>{{Cite journal |last1=Brownstein |first1=Chase Doran |last2=Harrington |first2=Richard C |last3=Near |first3=Thomas J. |date=July 2023 |title=The biogeography of extant lungfishes traces the breakup of Gondwana |url=https://onlinelibrary.wiley.com/doi/10.1111/jbi.14609 |journal=Journal of Biogeography |language=en |volume=50 |issue=7 |pages=1191–1198 |doi=10.1111/jbi.14609 |bibcode=2023JBiog..50.1191B |issn=0305-0270}}</ref> [[Mawsoniidae|Mawsoniids]], a marine and freshwater/brackish group of [[coelacanth]]s, which first appeared in North America during the Triassic, expanded into Europe and South America by the end of the Jurassic.<ref>{{Cite journal|last1=Cavin|first1=Lionel|last2=Cupello|first2=Camila|last3=Yabumoto|first3=Yoshitaka|last4=Léo|first4=Fragoso|last5=Deersi |first5=Uthumporn|last6=Brito|first6=Paul M.|date=2019|title=Phylogeny and evolutionary history of mawsoniid coelacanths |url=http://www.kmnh.jp/wp-content/uploads/2019/05/A17-3-Cavin.pdf|journal=Bulletin of the Kitakyushu Museum of Natural History and Human History, Series A|volume=17|pages=3–13}}</ref> The marine [[Latimeriidae]], which contains the living coelacanths of the genus ''[[Latimeria]]'', were also present in the Jurassic, having originated in the Triassic, with a number of records from the Jurassic of Europe including ''[[Swenzia]]'', thought to be the closest known relative of living coelacanths.<ref>{{Cite journal |last=Clement|first=Gaël|date=2005-09-30|title=A new coelacanth (Actinistia, Sarcopterygii) from the Jurassic of France, and the question of the closest relative fossil to Latimeria|url=http://www.tandfonline.com/doi/abs/10.1671/0272-4634%282005%29025%5B0481%3AANCASF%5D2.0.CO%3B2 |journal=Journal of Vertebrate Paleontology|language=en|volume=25|issue=3|pages=481–491|doi=10.1671/0272-4634(2005)025[0481:ANCASF]2.0.CO;2 |s2cid=86338307 |issn=0272-4634|url-access=subscription}}</ref>

==== Actinopterygii ====
[[File:Thrissops cf formosus 01.jpg|thumb|upright=1.15|Fossil of ''[[Thrissops]],'' an [[ichthyodectid]] stem-group teleost from the Late Jurassic Solnhofen Limestone of Germany, showing preserved colouration]]
Ray-finned fish ([[Actinopterygii]]) were major components of Jurassic freshwater and marine ecosystems. Archaic "[[Palaeonisciformes|palaeoniscoid]]" fish, which were common in both marine and freshwater habitats during the preceding Triassic declined during the Jurassic, being largely replaced by more [[Derived (phylogenetics)|derived]] actinopterygian lineages.<ref>{{Cite journal |last=Skrzycka |first=Roksana|date=2014-07-03|title=Revision of two relic actinopterygians from the Middle or Upper Jurassic Karabastau Formation, Karatau Range, Kazakhstan |url=http://www.tandfonline.com/doi/abs/10.1080/03115518.2014.880267|journal=Alcheringa: An Australasian Journal of Palaeontology |language=en|volume=38|issue=3|pages=364–390|doi=10.1080/03115518.2014.880267|bibcode=2014Alch...38..364S |s2cid=129308632|issn=0311-5518|url-access=subscription}}</ref> The oldest known [[Acipenseriformes]], the group that contains living [[sturgeon]] and [[paddlefish]], are from the Early Jurassic.<ref>{{Cite journal |last1=Hilton|first1=Eric J.|last2=Grande|first2=Lance|last3=Jin|first3=Fan|date=January 2021|title=Redescription of † Yanosteus longidorsalis Jin et al., (Chondrostei, Acipenseriformes, †Peipiaosteidae) from the Early Cretaceous of China |url=https://www.cambridge.org/core/product/identifier/S0022336020000803/type/journal_article|journal=Journal of Paleontology |language=en |volume=95 |issue=1|pages=170–183|doi=10.1017/jpa.2020.80|bibcode=2021JPal...95..170H |s2cid=225158727|issn=0022-3360|url-access=subscription}}</ref> [[Amiiformes|Amiiform]] fish (which today only includes the [[bowfin]]) first appeared during the Early Jurassic, represented by ''[[Caturus]]'' from the Pliensbachian of Britain; after their appearance in the western Tethys, they expanded to Africa, North America and Southeast and East Asia by the end of the Jurassic,<ref name="Poyato-Ariza-2020" /> with the modern family [[Amiidae]] appearing during the Late Jurassic.<ref>{{Cite journal |last1=Deesri |first1=Uthumporn |last2=Naksri |first2=Wilailuck |last3=Jintasakul |first3=Pratueng |last4=Noda |first4=Yoshikazu |last5=Yukawa |first5=Hirokazu |last6=Hossny |first6=Tamara El |last7=Cavin |first7=Lionel |date=2023-03-27 |title=A New Sinamiin Fish (Actinopterygii) from the Early Cretaceous of Thailand: Implications on the Evolutionary History of the Amiid Lineage |journal=Diversity |language=en |volume=15 |issue=4 |page=491 |doi=10.3390/d15040491 |issn=1424-2818 |doi-access=free |bibcode=2023Diver..15..491D }}</ref> [[Pycnodontiformes]], which first appeared in the western Tethys during the Late Triassic, expanded to South America and Southeast Asia by the end of the Jurassic, having a high diversity in Europe during the Late Jurassic.<ref name="Poyato-Ariza-2020">{{Cite journal|last1=Poyato-Ariza|first1=Francisco José|last2=Martín-Abad |first2=Hugo|date=2020-07-19|title=History of two lineages: Comparative analysis of the fossil record in Amiiformes and Pycnodontiformes (Osteischtyes, Actinopterygii)|url=https://ojs.uv.es/index.php/sjpalaeontology/article/view/17833|journal=Spanish Journal of Palaeontology |volume=28 |issue=1|page=79|doi=10.7203/sjp.28.1.17833|issn=2255-0550|doi-access=free|hdl=10486/710030|hdl-access=free}}</ref> During the Jurassic, the [[Ginglymodi]], the only living representatives being [[gar]]s (Lepisosteidae) were diverse in both freshwater and marine environments. The oldest known representatives of anatomically modern gars appeared during the Late Jurassic.<ref>{{Cite journal |last1=Brito |first1=Paulo M. |last2=Alvarado-Ortega|first2=Jésus|last3=Meunier|first3=François J.|date=December 2017|title=Earliest known lepisosteoid extends the range of anatomically modern gars to the Late Jurassic|journal=Scientific Reports |language=en |volume=7 |issue=1 |page=17830 |doi=10.1038/s41598-017-17984-w |issn=2045-2322|pmc=5736718|pmid=29259200|bibcode=2017NatSR...717830B}}</ref> Stem-group [[teleost]]s, which make up over 99% of living Actinopterygii, had first appeared during the Triassic in the western Tethys; they underwent a major diversification beginning in the Late Jurassic, with early representatives of modern teleost clades such as [[Elopomorpha]] and [[Osteoglossoidei]] appearing during this time.<ref>Arratia G. Mesozoic halecostomes and the early radiation of teleosts. In: Arratia G, Tintori A, editors. Mesozoic Fishes 3 – Systematics, Paleoenvironments and Biodiversity. München: Verlag Dr. Friedrich Pfeil; 2004. p. 279–315.</ref><ref>{{Cite journal |last1=Tse |first1=Tze-Kei |last2=Pittman |first2=Michael|last3=Chang|first3=Mee-mann|date=2015-03-26|title=A specimen of Paralycoptera Chang & Chou 1977 (Teleostei: Osteoglossoidei) from Hong Kong (China) with a potential Late Jurassic age that extends the temporal and geographical range of the genus |journal=PeerJ |language=en|volume=3|article-number=e865|doi=10.7717/peerj.865|pmid=25834774|pmc=4380157|issn=2167-8359 |doi-access=free }}</ref> The [[Pachycormiformes]], a group of marine stem-teleosts, first appeared in the Early Jurassic and included both [[tuna]]-like predatory and filter-feeding forms, the latter included the largest bony fish known to have existed: ''[[Leedsichthys]]'', with an estimated maximum length of over 15 metres, known from the late Middle to Late Jurassic.<ref name="Liston2013">Liston, J., Newbrey, M., Challands, T., and Adams, C., 2013, "Growth, age and size of the Jurassic pachycormid ''Leedsichthys problematicus'' (Osteichthyes: Actinopterygii) in: Arratia, G., Schultze, H. and Wilson, M. (eds.) ''Mesozoic Fishes 5 – Global Diversity and Evolution''. Verlag Dr. Friedrich Pfeil, München, Germany, pp. 145–175</ref>

==== Chondrichthyes ====
[[File:Naturkundemuseum Engelhai Pseudorhina sp.17RM1984.jpg|thumb|Fossil of ''[[Pseudorhina]]'' from the Late Jurassic of Germany, a close relative of modern [[angelshark]]s.]]
During the Early Jurassic, the shark-like [[Hybodontiformes|hybodonts]], which represented the dominant group of [[Chondrichthyes|chondrichthyans]] during the preceding Triassic, were common in both marine and freshwater settings; however, by the Late Jurassic, hybodonts had become minor components of most marine communities, having been largely replaced by modern [[Neoselachii|neoselachians]], but remained common in freshwater and restricted marine environments.<ref>{{Cite journal |last1=Rees |first1=Jan |last2=Underwood |first2=Charlie J. |date=2008-01-17 |title=Hybodont sharks of the English Bathonian and Callovian (Middle Jurassic) |journal=Palaeontology |language=en |volume=51 |issue=1 |pages=117–147 |doi=10.1111/j.1475-4983.2007.00737.x |bibcode=2008Palgy..51..117R |doi-access=free}}</ref><ref>{{Cite journal |last1=Corso |first1=Jacopo Dal |last2=Bernardi |first2=Massimo |last3=Sun |first3=Yadong |last4=Song |first4=Haijun |last5=Seyfullah |first5=Leyla J. |last6=Preto |first6=Nereo |last7=Gianolla |first7=Piero |last8=Ruffell |first8=Alastair |last9=Kustatscher |first9=Evelyn |last10=Roghi |first10=Guido |last11=Merico |first11=Agostino |date=September 2020 |title=Extinction and dawn of the modern world in the Carnian (Late Triassic) |journal=Science Advances |volume=6 |issue=38 |article-number=eaba0099 |language=EN |doi=10.1126/sciadv.aba0099 |pmc=7494334 |pmid=32938682 |bibcode=2020SciA....6...99D}}</ref> The Neoselachii, which contains all living sharks and rays, radiated beginning in the Early Jurassic.<ref>{{Cite journal |last=Underwood |first=Charlie J. |date=March 2006 |title=Diversification of the Neoselachii (Chondrichthyes) during the Jurassic and Cretaceous |url=http://www.bioone.org/doi/abs/10.1666/04069.1 |journal=Paleobiology |language=en |volume=32 |issue=2 |pages=215–235 |doi=10.1666/04069.1 |bibcode=2006Pbio...32..215U |s2cid=86232401 |issn=0094-8373}}</ref> The oldest known ray ([[Batoidea]]) is ''[[Antiquaobatis]]'' from the Pliensbachian of Germany.<ref>{{Cite journal |last1=Stumpf |first1=Sebastian |last2=Kriwet |first2=Jürgen |date=2019-12-01 |title=A new Pliensbachian elasmobranch (Vertebrata, Chondrichthyes) assemblage from Europe, and its contribution to the understanding of late Early Jurassic elasmobranch diversity and distributional patterns |journal=PalZ |language=en |volume=93 |issue=4 |pages=637–658 |doi=10.1007/s12542-019-00451-4 |issn=1867-6812 |doi-access=free |bibcode=2019PalZ...93..637S |s2cid=181782998}}</ref> Jurassic batoids known from complete remains retain a conservative, [[guitarfish]]-like morphology.<ref>{{Cite journal |last1=Underwood |first1=Charlie J. |last2=Claeson |first2=Kerin M. |date=June 2019 |title=The Late Jurassic ray Kimmerobatis etchesi gen. et sp. nov. and the Jurassic radiation of the Batoidea |url=https://linkinghub.elsevier.com/retrieve/pii/S0016787817300949 |journal=Proceedings of the Geologists' Association |language=en |volume=130 |issue=3–4 |pages=345–354 |doi=10.1016/j.pgeola.2017.06.009 |bibcode=2019PrGA..130..345U |s2cid=90691006}}</ref> The oldest known [[Hexanchiformes]] and [[carpet shark]]s (Orectolobiformes) are from the Early Jurassic (Pliensbachian and Toarcian, respectively) of Europe.<ref>{{Cite journal|last1=Kriwet|first1=Jürgen|last2=Klug|first2=Stefanie|date=December 2011|title=A new Jurassic cow shark (Chondrichthyes, Hexanchiformes) with comments on Jurassic hexanchiform systematics|journal=[[Swiss Journal of Geosciences]]|language=en|volume=104|issue=S1|pages=107–114|doi=10.1007/s00015-011-0075-z|s2cid=84405176|issn=1661-8726|doi-access=free|bibcode=2011SwJG..104..107K }}</ref><ref>{{Cite journal |last1=Srdic |first1=Alex |last2=Duffin |first2=Christopher J. |last3=Martill |first3=David M. |date=August 2016 |title=First occurrence of the orectolobiform shark Akaimia in the Oxford Clay Formation (Jurassic, Callovian) of England |url=https://linkinghub.elsevier.com/retrieve/pii/S0016787816300785 |journal=Proceedings of the Geologists' Association |language=en |volume=127 |issue=4 |pages=506–513 |doi=10.1016/j.pgeola.2016.07.002|bibcode=2016PrGA..127..506S }}</ref> The oldest known members of the [[Heterodontiformes]], the only living members of which are the [[bullhead shark]] (''Heterodontus''), first appeared in the Early Jurassic, with representatives of the living genus appearing during the Late Jurassic.<ref>{{Cite journal |last1=Slater |first1=Tiffany S. |last2=Ashbrook |first2=Kate |last3=Kriwet |first3=Jürgen |date=August 2020 |editor-last=Cavin |editor-first=Lionel |title=Evolutionary relationships among bullhead sharks (Chondrichthyes, Heterodontiformes) |url=https://onlinelibrary.wiley.com/doi/10.1002/spp2.1299 |journal=Papers in Palaeontology |language=en |volume=6 |issue=3 |pages=425–437 |doi=10.1002/spp2.1299 |bibcode=2020PPal....6..425S |s2cid=214133104 |issn=2056-2802 |hdl=10468/10339 |hdl-access=free}}</ref> The oldest record of angelsharks ([[Squatiniformes]]) is ''[[Pseudorhina]]'' from the Late Jurassic (Oxfordian–Tithonian) of Europe, which already has a bodyform similar to members of the only living genus of the order, ''[[Squatina]]''.<ref>{{Cite journal |last1=López-Romero |first1=Faviel A. |last2=Stumpf |first2=Sebastian |last3=Pfaff |first3=Cathrin |last4=Marramà |first4=Giuseppe |last5=Johanson |first5=Zerina |last6=Kriwet |first6=Jürgen |date=2020-07-28 |title=Evolutionary trends of the conserved neurocranium shape in angel sharks (Squatiniformes, Elasmobranchii) |journal=Scientific Reports |language=en |volume=10 |issue=1 |page=12582 |doi=10.1038/s41598-020-69525-7 |pmid=32724124 |pmc=7387474 |bibcode=2020NatSR..1012582L |issn=2045-2322}}</ref> The oldest known remains of [[Carcharhiniformes]], the largest order of living sharks, first appear in the late Middle Jurassic (Bathonian) of the western Tethys (England and Morocco). Known dental and exceptionally preserved body remains of Jurassic Carchariniformes are similar to those of living [[Scyliorhinidae|catshark]]s.<ref>{{Cite journal |last1=Stumpf |first1=Sebastian |last2=Scheer |first2=Udo |last3=Kriwet |first3=Jürgen |date=2019-03-04 |title=A new genus and species of extinct ground shark, †Diprosopovenator hilperti, gen. et sp. nov. (Carcharhiniformes, †Pseudoscyliorhinidae, fam. nov.), from the Upper Cretaceous of Germany |journal=Journal of Vertebrate Paleontology |volume=39 |issue=2 |article-number=e1593185 |doi=10.1080/02724634.2019.1593185 |bibcode=2019JVPal..39E3185S |s2cid=155785248 |issn=0272-4634 |doi-access=free}}</ref> [[Synechodontiformes]], an extinct group of sharks closely related to Neoselachii, were also widespread during the Jurassic.<ref>{{Cite journal |last1=Klug |first1=Stefanie |last2=Tütken |first2=Thomas |last3=Wings |first3=Oliver |last4=Pfretzschner |first4=Hans-Ulrich |last5=Martin |first5=Thomas |date=September 2010 |title=A Late Jurassic freshwater shark assemblage (Chondrichthyes, Hybodontiformes) from the southern Junggar Basin, Xinjiang, Northwest China |url=http://link.springer.com/10.1007/s12549-010-0032-2 |journal=Palaeobiodiversity and Palaeoenvironments |language=en |volume=90 |issue=3 |pages=241–257|doi=10.1007/s12549-010-0032-2 |bibcode=2010PdPe...90..241K |s2cid=129236098 |issn=1867-1594|url-access=subscription }}</ref> The oldest remains of modern [[chimaera]]s are from the Early Jurassic of Europe, with members of the living family [[Callorhinchidae]] appearing during the Middle Jurassic. Unlike most living chimaeras, Jurassic chimeras are often found in shallow water environments.<ref>{{Cite journal |last1=Popov |first1=Evgeny V. |last2=Delsate |first2=Dominique |last3=Felten |first3=Roland |date=2019-07-02 |title=A New Callorhinchid Genus (Holocephali, Chimaeroidei) from the Early Bajocian of Ottange-Rumelange, on the Luxembourg-French Border |url=https://bioone.org/journals/paleontological-research/volume-23/issue-3/2018PR021/A-New-Callorhinchid-Genus-Holocephali-Chimaeroidei-from-the-Early-Bajocian/10.2517/2018PR021.full |journal=Paleontological Research |volume=23 |issue=3 |page=220 |doi=10.2517/2018PR021 |bibcode=2019PalRe..23..220P |s2cid=198423356 |issn=1342-8144|url-access=subscription }}</ref> The closely related [[Myriacanthidae|myriacanthids]] and the flattened ''[[Squaloraja]]'' are also known from the Jurassic of Europe.<ref>{{Cite journal |last1=Duffin|first1=Christopher J. |last2=Milàn |first2=Jesper |date=2017-11-14|title=A new myriacanthid holocephalian from the Early Jurassic of Denmark |url=https://2dgf.dk/publikationer/bulletin/bulletin-volume-65-2017/#10 |journal=Bulletin of the Geological Society of Denmark |language=en |volume=65 |pages=161–170|doi=10.37570/bgsd-2017-65-10|issn=2245-7070 |doi-access=free|bibcode=2017BuGSD..65..161D }}</ref>

=== Insects and arachnids ===
[[File:Lichnomesopsyche daohugouensis.jpg|left|thumb|''[[Lichnomesopsyche|Lichnomesopsyche daohugouensis]]'', an extinct [[Mesopsychidae|mesopsychid]] [[Mecoptera|scorpionfly]] from the Late Jurassic of China]]
There appears to have been no major extinction of insects at the Triassic–Jurassic boundary.<ref name="Lucas-2015" /> Many important insect fossil localities are known from the Jurassic of Eurasia, the most important being the [[Karabastau Formation]] of Kazakhstan and the various Yanliao Biota deposits in Inner Mongolia, China, such as the Daohugou Bed, dating to the Callovian–Oxfordian. The diversity of insects stagnated throughout the Early and Middle Jurassic, but during the latter third of the Jurassic origination rates increased substantially while extinction rates remained flat.<ref>{{Citation|last=Labandeira|first=Conrad C.|title=The Fossil History of Insect Diversity|date=2018-05-23 |work=Insect Biodiversity|pages=723–788|place=Chichester, UK|publisher=John Wiley & Sons, Ltd|language=en|doi=10.1002/9781118945582.ch24|isbn=978-1-118-94558-2}}</ref> The increasing diversity of insects in the Middle–Late Jurassic corresponds with a substantial increase in the diversity of [[insect mouthparts]].<ref>{{Cite journal|last1=Nel|first1=Patricia|last2=Bertrand|first2=Sylvain|last3=Nel|first3=André|date=December 2018|title=Diversification of insects since the Devonian: a new approach based on morphological disparity of mouthparts|journal=Scientific Reports|language=en|volume=8|issue=1|page=3516|doi=10.1038/s41598-018-21938-1|issn=2045-2322|pmc=5824790|pmid=29476087|bibcode=2018NatSR...8.3516N}}</ref> The Middle to Late Jurassic was a time of major diversification for [[beetle]]s,<ref>{{Cite journal|last1=McKenna|first1=Duane D.|last2=Shin|first2=Seunggwan|last3=Ahrens|first3=Dirk|last4=Balke|first4=Michael|last5=Beza-Beza|first5=Cristian|last6=Clarke|first6=Dave J.|last7=Donath|first7=Alexander|last8=Escalona|first8=Hermes E.|last9=Friedrich|first9=Frank|last10=Letsch|first10=Harald|last11=Liu|first11=Shanlin|date=2019-12-03|title=The evolution and genomic basis of beetle diversity|journal=Proceedings of the National Academy of Sciences|language=en|volume=116|issue=49|pages=24729–24737|doi=10.1073/pnas.1909655116|issn=0027-8424|pmc=6900523|pmid=31740605|bibcode=2019PNAS..11624729M |doi-access=free}}</ref> particularly for the suborder [[Polyphaga]], which represents 90% of living beetle species but which was rare during the preceding Triassic.<ref>{{Cite journal |last1=Beutel |first1=Rolf G. |last2=Xu |first2=Chunpeng |last3=Jarzembowski |first3=Edmund |last4=Kundrata |first4=Robin |last5=Boudinot |first5=Brendon E. |last6=McKenna |first6=Duane D. |last7=Goczał |first7=Jakub |date=13 February 2024 |title=The evolutionary history of Coleoptera (Insecta) in the late Palaeozoic and the Mesozoic |journal=Systematic Entomology |language=en |volume=49 |issue=3 |pages=355–388 |doi=10.1111/syen.12623 |bibcode=2024SysEn..49..355B |issn=0307-6970|doi-access=free }}</ref> [[Weevil]]s first appear in the fossil record during the Middle to Late Jurassic, but are suspected to have originated during the Late Triassic to Early Jurassic.<ref>{{Cite journal|last1=Shin|first1=Seunggwan|last2=Clarke|first2=Dave J|last3=Lemmon|first3=Alan R|last4=Moriarty Lemmon|first4=Emily|last5=Aitken|first5=Alexander L|last6=Haddad|first6=Stephanie|last7=Farrell|first7=Brian D|last8=Marvaldi|first8=Adriana E|last9=Oberprieler|first9=Rolf G|last10=McKenna|first10=Duane D|date=2018-04-01|title=Phylogenomic Data Yield New and Robust Insights into the Phylogeny and Evolution of Weevils|url=https://academic.oup.com/mbe/article/35/4/823/4765916|journal=Molecular Biology and Evolution|language=en|volume=35|issue=4|pages=823–836|doi=10.1093/molbev/msx324|issn=0737-4038|pmid=29294021|s2cid=4366092|doi-access=free|hdl=11336/57287|hdl-access=free}}</ref> [[Orthoptera]]n diversity had declined during the Late Triassic, but recovered during the Early Jurassic,<ref>{{Cite journal |last1=Xu |first1=Chunpeng |last2=Fang |first2=Yanan |last3=Fang |first3=Yan |last4=Wang |first4=He |last5=Zhou |first5=Qian |last6=Jiang |first6=Xueying |last7=Zhang |first7=Haichun |date=14 February 2024 |title=Early Jurassic orthopteran insects from the southern Junggar Basin, NW China, with discussion of biodiversity changes of Orthoptera across the Triassic–Jurassic boundary |url=https://www.lyellcollection.org/doi/10.1144/SP538-2021-184 |journal=Geological Society, London, Special Publications |language=en |volume=538 |issue=1 |pages=147–154 |doi=10.1144/SP538-2021-184 |issn=0305-8719 |access-date=22 June 2024 |via=Lyell Collection Geological Society Publications|url-access=subscription }}</ref> with the [[Hagloidea]], a superfamily of [[ensifera]]n orthopterans today confined to a few living species, being particularly diverse during the Jurassic.<ref>{{Cite journal |last1=Woodrow |first1=Charlie |last2=Baker |first2=Ed |last3=Jonsson |first3=Thorin |last4=Montealegre-Z |first4=Fernando |date=2022-08-10 |editor-last=Nityananda |editor-first=Vivek |title=Reviving the sound of a 150-year-old insect: The bioacoustics of Prophalangopsis obscura (Ensifera: Hagloidea) |journal=PLOS ONE |language=en |volume=17 |issue=8 |article-number=e0270498 |doi=10.1371/journal.pone.0270498 |doi-access=free |issn=1932-6203 |pmc=9365155 |pmid=35947546|bibcode=2022PLoSO..1770498W }}</ref> The oldest known [[lepidoptera]]ns (the group containing butterflies and moths) are known from the Triassic–Jurassic boundary, with wing scales belonging to the suborder [[Glossata]] and [[Micropterigidae]]-grade moths from the deposits of this age in Germany.<ref>{{Cite journal|last1=van Eldijk|first1=Timo J. B.|last2=Wappler|first2=Torsten|last3=Strother|first3=Paul K.|last4=van der Weijst|first4=Carolien M. H.|last5=Rajaei|first5=Hossein|last6=Visscher|first6=Henk|last7=van de Schootbrugge|first7=Bas|date=January 2018|title=A Triassic-Jurassic window into the evolution of Lepidoptera|url= |journal=Science Advances|language=en|volume=4|issue=1|article-number=e1701568|bibcode=2018SciA....4.1568V|doi=10.1126/sciadv.1701568|issn=2375-2548|pmc=5770165|pmid=29349295}}</ref> Modern representatives of both [[Dragonfly|dragonflies]] and [[Damselfly|damselflies]] also first appeared during the Jurassic.<ref>{{Cite journal|last1=Kohli|first1=Manpreet Kaur|last2=Ware|first2=Jessica L.|last3=Bechly|first3=Günter|date=2016|title=How to date a dragonfly: Fossil calibrations for odonates|url=http://palaeo-electronica.org/content/fc-8|journal=Palaeontologia Electronica|volume=19|issue=1|page=576 |doi=10.26879/576|doi-access=free|bibcode=2016PalEl..19..576K }}</ref> Although modern representatives are not known until the Cenozoic, [[ectoparasitic]] insects thought to represent primitive [[flea]]s, belonging to the family [[Pseudopulicidae]], are known from the Middle Jurassic of Asia. These insects are substantially different from modern fleas, lacking the specialised morphology of the latter and being larger.<ref>{{Cite journal|last1=Huang|first1=DiYing|last2=Engel|first2=Michael S.|last3=Cai|first3=ChenYang|last4=Nel|first4=André|date=May 2013|title=Mesozoic giant fleas from northeastern China (Siphonaptera): Taxonomy and implications for palaeodiversity|journal=Chinese Science Bulletin|language=en|volume=58|issue=14|pages=1682–1690|bibcode=2013ChSBu..58.1682H|doi=10.1007/s11434-013-5769-3|issn=1001-6538|s2cid=53578959|doi-access=free|hdl=1808/14426|hdl-access=free}}</ref><ref>{{Cite journal|last1=Gao|first1=Taiping|last2=Shih|first2=Chungkun|last3=Rasnitsyn|first3=Alexandr P.|last4=Xu|first4=Xing|last5=Wang|first5=Shuo|last6=Ren|first6=Dong|date=July 2013|title=New Transitional Fleas from China Highlighting Diversity of Early Cretaceous Ectoparasitic Insects|journal=Current Biology|language=en|volume=23|issue=13|pages=1261–1266|doi=10.1016/j.cub.2013.05.040|pmid=23810530|s2cid=9646168|doi-access=free|bibcode=2013CBio...23.1261G }}</ref> [[Parasitoid wasp]]s ([[Apocrita]]) first appeared during the Early Jurassic and subsequently became widespread, reshaping terrestrial food webs.<ref>{{Citation|last1=Labandeira|first1=Conrad C.|title=The History of Insect Parasitism and the Mid-Mesozoic Parasitoid Revolution|date=2021|url=https://link.springer.com/10.1007/978-3-030-42484-8_11|work=The Evolution and Fossil Record of Parasitism|volume=49|pages=377–533|editor-last=De Baets|editor-first=Kenneth|place=Cham|publisher=Springer International Publishing|language=en|doi=10.1007/978-3-030-42484-8_11|isbn=978-3-030-42483-1|access-date=2021-12-02|last2=Li|first2=Longfeng|series=Topics in Geobiology |s2cid=236738176|editor2-last=Huntley|editor2-first=John Warren|url-access=subscription}}</ref> The Jurassic saw also saw the first appearances of several other groups of insects, including [[Phasmatodea]] (stick insects),<ref>{{Cite journal|last1=Yang|first1=Hongru|last2=Shi|first2=Chaofan|last3=Engel|first3=Michael S|last4=Zhao|first4=Zhipeng|last5=Ren|first5=Dong|last6=Gao|first6=Taiping|date=2020-04-02|title=Early specializations for mimicry and defense in a Jurassic stick insect|journal=National Science Review|volume=8|issue=1|language=en|article-number=nwaa056|doi=10.1093/nsr/nwaa056|pmid=34691548|pmc=8288419|issn=2095-5138|doi-access=free}}</ref> [[Mantophasmatidae]] (gladiators),<ref>{{Cite journal|last1=Huang|first1=Di-ying|last2=Nel|first2=André|last3=Zompro|first3=Oliver|last4=Waller|first4=Alain|date=2008-06-11|title=Mantophasmatodea now in the Jurassic|url=https://www.researchgate.net/publication/5311278|journal=Naturwissenschaften|volume=95|issue=10|pages=947–952|bibcode=2008NW.....95..947H|doi=10.1007/s00114-008-0412-x|issn=0028-1042|pmid=18545982|s2cid=35408984}}</ref> [[Embioptera]] (webspinners),<ref>{{Cite journal|last1=Huang|first1=Di-Ying|last2=Nel|first2=André|date=August 2009|title=Oldest webspinners from the Middle Jurassic of Inner Mongolia, China (Insecta: Embiodea)|journal=Zoological Journal of the Linnean Society|language=en|volume=156|issue=4|pages=889–895|doi=10.1111/j.1096-3642.2008.00499.x|doi-access=free}}</ref> and [[Raphidioptera]] (snakeflies).<ref>{{Cite journal |last1=Engel |first1=Michael S. |last2=Winterton |first2=Shaun L. |last3=Breitkreuz |first3=Laura C.V. |date=2018-01-07 |title=Phylogeny and Evolution of Neuropterida: Where Have Wings of Lace Taken Us? |url=https://www.annualreviews.org/doi/10.1146/annurev-ento-020117-043127 |journal=Annual Review of Entomology |language=en |volume=63 |issue=1 |pages=531–551 |doi=10.1146/annurev-ento-020117-043127 |pmid=29324039 |issn=0066-4170|url-access=subscription }}</ref> The earliest [[scale insect]] (Coccomorpha) '''i'''s known from amber dating to the Late Jurassic, though the group probably originated earlier during the Triassic.<ref name="Jankotejacoccidae">{{Cite journal |last1=Vršanský |first1=P. |last2=Sendi |first2=H. |last3=Kotulová |first3=J. |last4=Szwedo |first4=J. |last5=Havelcová |first5=M. |last6=Palková |first6=H. |last7=Vršanská |first7=L. |last8=Sakala |first8=J. |last9=Puškelová |first9=L. |last10=Golej |first10=M. |last11=Biroň |first11=A. |last12=Peyrot |first12=D. |last13=Quicke |first13=D. |last14=Néraudeau |first14=D. |last15=Uher |first15=P. |year=2024 |title=Jurassic Park approached: a coccid from Kimmeridgian cheirolepidiacean Aintourine Lebanese amber |journal=National Science Review |at=nwae200 |doi=10.1093/nsr/nwae200 |doi-access=free |last16=Maksoud |first16=S. |last17=Azar |first17=D.|volume=12 |issue=3 |pmid=40070804 |pmc=11895504 }}</ref> 
[[File:Mongolarachne.jpg|thumb|''[[Mongolarachne]]'' from the Late Jurassic of China]]
Only a handful of records of mites are known from the Jurassic, including ''[[Jureremus]]'', an [[Oribatida|oribatid]] mite belonging to the family [[Cymbaeremaeidae]] known from the Late Jurassic of Britain and Russia,<ref>{{Cite journal|last1=Selden|first1=Paul A.|last2=Baker|first2=Anne S.|last3=Phipps|first3=Kenneth J.|date=2008|title=An Oribatid Mite (arachnida: Acari) from the Oxford Clay (jurassic: Upper Callovian) of South Cave Station Quarry, Yorkshire, Uk|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1475-4983.2008.00769.x|journal=Palaeontology|language=en|volume=51|issue=3|pages=623–633|doi=10.1111/j.1475-4983.2008.00769.x|bibcode=2008Palgy..51..623S |issn=1475-4983|hdl=1808/8353|s2cid=54046836 |hdl-access=free}}</ref> and a member of the still living orbatid genus ''[[Hydrozetes]]'' from the Early Jurassic of Sweden.<ref>{{Cite journal|last1=Sivhed|first1=Ulf|last2=Wallwork|first2=John A.|date=March 1978|title=An Early Jurassic oribatid mite from southern Sweden|url=https://www.tandfonline.com/doi/full/10.1080/11035897809448562|journal=Geologiska Föreningen i Stockholm Förhandlingar|language=en|volume=100|issue=1|pages=65–70|doi=10.1080/11035897809448562|issn=0016-786X|url-access=subscription}}</ref> Spiders diversified through the Jurassic.<ref name="Magalhaes-2020">{{Cite journal|last1=Magalhaes|first1=Ivan L. F.|last2=Azevedo|first2=Guilherme H. F.|last3=Michalik|first3=Peter|last4=Ramírez|first4=Martín J.|date=February 2020|title=The fossil record of spiders revisited: implications for calibrating trees and evidence for a major faunal turnover since the Mesozoic|url=https://onlinelibrary.wiley.com/doi/abs/10.1111/brv.12559|journal=Biological Reviews|language=en|volume=95|issue=1|pages=184–217|doi=10.1111/brv.12559|issn=1464-7931|pmid=31713947|s2cid=207937170|url-access=subscription}}</ref> The Early Jurassic ''[[Seppo koponeni]]'' may represent a stem group to [[Palpimanoidea]].<ref name="Seppo">{{cite journal|last1=Selden|first1=Paul A.|last2=Dunlop|first2=Jason A.|year=2014|title=The first fossil spider (Araneae: Palpimanoidea) from the Lower Jurassic (Grimmen, Germany)|journal=Zootaxa|volume=3894|issue=1|pages=161–168|doi=10.11646/zootaxa.3894.1.13|pmid=25544628|url=http://publication.plazi.org/id/FF9246404B55FFEED2268C59FFFB522F }}</ref> ''[[Eoplectreurys]]'' from the Middle Jurassic of China is considered a stem lineage of [[Synspermiata]]. The oldest member of the family [[Archaeidae]], ''[[Patarchaea]]'', is known from the Middle Jurassic of China.<ref name="Magalhaes-2020" /> ''[[Mongolarachne]]'' from the Middle Jurassic of China is among the largest known fossil spiders, with legs over 5 centimetres long.<ref name="Selden2013">{{cite journal|last1=Selden|first1=P. A.|last2=Shih|first2=C.K.|last3=Ren|first3=D.|year=2013|title=A giant spider from the Jurassic of China reveals greater diversity of the orbicularian stem group|journal=Naturwissenschaften|volume=100|issue=12|pages=1171–1181|bibcode=2013NW....100.1171S|doi=10.1007/s00114-013-1121-7|pmc=3889289|pmid=24317464}}</ref> The only scorpion known from the Jurassic is ''[[Liassoscorpionides]]'' from the Early Jurassic of Germany, of uncertain placement.<ref>{{Cite journal|last1=Dunlop|first1=Jason A.|last2=Kamenz|first2=Carsten|last3=Scholtz|first3=Gerhard|date=June 2007|title=Reinterpreting the morphology of the Jurassic scorpion Liassoscorpionides|url=https://linkinghub.elsevier.com/retrieve/pii/S1467803906000673|journal=Arthropod Structure & Development|language=en|volume=36|issue=2|pages=245–252|doi=10.1016/j.asd.2006.09.003|pmid=18089103|bibcode=2007ArtSD..36..245D |url-access=subscription}}</ref> [[Eupnoi]] harvestmen ([[Opiliones]]) are known from the Middle Jurassic of China, including members of the family [[Sclerosomatidae]].<ref>{{Cite journal|last1=Huang|first1=Diying|last2=Selden|first2=Paul A.|last3=Dunlop|first3=Jason A.|date=August 2009|title=Harvestmen (Arachnida: Opiliones) from the Middle Jurassic of China|url=http://link.springer.com/10.1007/s00114-009-0556-3|journal=Naturwissenschaften|language=en|volume=96|issue=8|pages=955–962|bibcode=2009NW.....96..955H|doi=10.1007/s00114-009-0556-3|issn=0028-1042|pmid=19495718|s2cid=9570512|url-access=subscription}}</ref><ref>{{Cite journal|last1=Giribet|first1=Gonzalo|last2=Tourinho|first2=Ana Lúcia|last3=Shih|first3=ChungKun|last4=Ren|first4=Dong|date=March 2012|title=An exquisitely preserved harvestman (Arthropoda, Arachnida, Opiliones) from the Middle Jurassic of China|url=http://link.springer.com/10.1007/s13127-011-0067-x|journal=Organisms Diversity & Evolution|language=en|volume=12|issue=1|pages=51–56|doi=10.1007/s13127-011-0067-x|bibcode=2012ODivE..12...51G |issn=1439-6092|s2cid=15658216|url-access=subscription}}</ref>

=== Marine invertebrates ===

==== End-Triassic extinction ====
During the end-Triassic extinction, 46%–72% of all marine genera became extinct. The effects of the end Triassic extinction were greatest at tropical latitudes and were more severe in Panthalassa than the Tethys or Boreal oceans. Tropical reef ecosystems collapsed during the event, and would not fully recover until much later in the Jurassic. [[Sessility (motility)|Sessile]] [[filter feeder]]s and [[photosymbiotic]] organisms were among those most severely affected.<ref>{{Cite journal|last1=Dunhill|first1=Alexander M.|last2=Foster|first2=William J.|last3=Sciberras|first3=James|last4=Twitchett|first4=Richard J.|date=January 2018|editor-last=Hautmann|editor-first=Michael|title=Impact of the Late Triassic mass extinction on functional diversity and composition of marine ecosystems |journal=Palaeontology|language=en|volume=61|issue=1|pages=133–148|doi=10.1111/pala.12332|bibcode=2018Palgy..61..133D |doi-access=free}}</ref>

==== Marine ecosystems ====
Having declined at the Triassic–Jurassic boundary, reefs substantially expanded during the Late Jurassic, including both [[sponge reef]]s and [[scleractinia]]n [[coral reef]]s. Late Jurassic reefs were similar in form to modern reefs but had more microbial carbonates and hypercalcified [[sponge]]s, and had weak biogenic binding. Reefs sharply declined at the close of the Jurassic,<ref>{{Cite journal|last=Kiessling|first=Wolfgang|date=December 2009|title=Geologic and Biologic Controls on the Evolution of Reefs|url=http://www.annualreviews.org/doi/10.1146/annurev.ecolsys.110308.120251|journal=Annual Review of Ecology, Evolution, and Systematics|language=en|volume=40|issue=1|pages=173–192|doi=10.1146/annurev.ecolsys.110308.120251|issn=1543-592X|url-access=subscription}}</ref> which caused an associated drop in diversity in [[Decapoda|decapod]] crustaceans.<ref name="Klompmaker-2013">{{Cite journal|last1=Klompmaker|first1=A. A.|last2=Schweitzer|first2=C. E.|last3=Feldmann|first3=R. M.|last4=Kowalewski|first4=M.|date=2013-11-01|title=The influence of reefs on the rise of Mesozoic marine crustaceans|url=https://pubs.geoscienceworld.org/geology/article/41/11/1179-1182/131064|journal=Geology|language=en|volume=41|issue=11|pages=1179–1182|doi=10.1130/G34768.1|bibcode=2013Geo....41.1179K|issn=0091-7613|url-access=subscription}}</ref> The earliest planktonic foraminifera, which constitute the suborder [[Globigerinina]], are known from the late Early Jurassic (mid-Toarcian) of the western Tethys, expanding across the whole Tethys by the Middle Jurassic and becoming globally distributed in tropical latitudes by the Late Jurassic.<ref>{{Cite journal|last1=Hudson|first1=Wendy|last2=Hart|first2=Malcolm B.|last3=Smart|first3=Christopher W.|date=2009-01-01|title=Palaeobiogeography of early planktonic foraminifera|url=https://pubs.geoscienceworld.org/sgf/bsgf/article/180/1/27/123101/Palaeobiogeography-of-early-planktonic|journal=Bulletin de la Société Géologique de France|language=en|volume=180|issue=1|pages=27–38|doi=10.2113/gssgfbull.180.1.27|issn=1777-5817|url-access=subscription}}</ref> [[Coccolithophore]]s and [[dinoflagellate]]s, which had first appeared during the Triassic, radiated during the Early to Middle Jurassic, becoming prominent members of the [[phytoplankton]].<ref>{{Cite journal|last1=Wiggan|first1=Nickolas J.|last2=Riding|first2=James B.|last3=Fensome|first3=Robert A.|last4=Mattioli|first4=Emanuela|date=2018-05-01|title=The Bajocian (Middle Jurassic): A key interval in the early Mesozoic phytoplankton radiation|url=http://www.sciencedirect.com/science/article/pii/S0012825217305214|journal=Earth-Science Reviews|language=en|volume=180|pages=126–146|bibcode=2018ESRv..180..126W|doi=10.1016/j.earscirev.2018.03.009|issn=0012-8252}}</ref> [[Microconchida|Microconchid]] tube worms, the last remaining order of [[Tentaculita]], a group of animals of uncertain affinities that were convergent on ''[[Spirorbis]]'' tube worms, were rare after the Triassic and had become reduced to the single genus ''[[Punctaconchus]],'' which became extinct in the late Bathonian.<ref>{{Cite journal|last1=Zatoń|first1=M.|last2=Taylor|first2=P.D.|date=2009-12-31|title=Microconchids (Tentaculita) from the Middle Jurassic of Poland|url=http://www.geology.cz/bulletin/contents/art1167|journal=Bulletin of Geosciences|language=en|pages=653–660|doi=10.3140/bull.geosci.1167|issn=1802-8225|doi-access=free}}</ref> The oldest known [[diatom]] is from Late Jurassic–aged amber from Thailand, assigned to the living genus ''[[Hemiaulus]].''<ref>{{Cite journal|last1=Girard|first1=Vincent|last2=Saint Martin|first2=Simona|last3=Buffetaut|first3=Eric|last4=Saint Martin|first4=Jean-Paul|last5=Néraudeau|first5=Didier|last6=Peyrot|first6=Daniel|last7=Roghi|first7=Guido|last8=Ragazzi|first8=Eugenio|last9=Suteethorn|first9=Varavudh|date=2020|editor-last=Saint Martin|editor-first=J.-P.|editor2-last=Saint Martin|editor2-first=S.|title=Thai amber: insights into early diatom history?|journal=BSGF – Earth Sciences Bulletin|volume=191|page=23|doi=10.1051/bsgf/2020028|issn=1777-5817|doi-access=free|hdl=11577/3391076|hdl-access=free}}</ref>

==== Echinoderms ====
[[Crinoid]]s diversified throughout the Jurassic, reaching their peak Mesozoic diversity during the Late Jurassic, primarily due to the radiation of sessile forms belonging to the orders [[Cyrtocrinida]] and [[Millericrinida]].<ref>{{Cite journal|last1=Gorzelak|first1=Przemysław|last2=Salamon|first2=Mariusz A.|last3=Trzęsiok|first3=Dawid|last4=Lach|first4=Rafał|last5=Baumiller|first5=Tomasz K.|date=April 2016|title=Diversity dynamics of post-Palaeozoic crinoids – in quest of the factors affecting crinoid macroevolution|url=https://onlinelibrary.wiley.com/doi/10.1111/let.12141|journal=Lethaia|language=en|volume=49|issue=2|pages=231–244|doi=10.1111/let.12141|bibcode=2016Letha..49..231G |url-access=subscription}}</ref> [[Sea urchin|Echinoids]] (sea urchins) underwent substantial diversification beginning in the Early Jurassic, primarily driven by the radiation of irregular (asymmetrical) forms, which were adapting to deposit feeding. Rates of diversification sharply dropped during the Late Jurassic.<ref>{{Cite journal|last1=Hopkins|first1=Melanie J.|last2=Smith|first2=Andrew B.|date=2015-03-24|title=Dynamic evolutionary change in post-Paleozoic echinoids and the importance of scale when interpreting changes in rates of evolution|journal=Proceedings of the National Academy of Sciences|language=en|volume=112|issue=12|pages=3758–3763|doi=10.1073/pnas.1418153112|issn=0027-8424|pmc=4378421|pmid=25713369|bibcode=2015PNAS..112.3758H|doi-access=free}}</ref>

==== Crustaceans ====
[[File:Eryon cuvieri Solnhofen.jpg|thumb|''[[Eryon]],'' a [[polychelida]]n decapod crustacean from the Late Jurassic of Germany.]]
The Jurassic was a significant time for the evolution of [[Decapoda|decapods]].<ref name="Klompmaker-2013" /> The first true crabs ([[Brachyura]]) are known from the Early Jurassic, with the earliest being ''[[Eocarcinus|Eocarcinus praecursor]]'' from the early Pliensbachian of England, which lacked the crab-like morphology ([[carcinisation]]) of modern crabs,<ref>{{Cite journal|last=Scholtz|first=Gerhard|date=November 2020|title=Eocarcinus praecursor Withers, 1932 (Malacostraca, Decapoda, Meiura) is a stem group brachyuran|journal=Arthropod Structure & Development|language=en|volume=59|article-number=100991|doi=10.1016/j.asd.2020.100991|pmid=32891896|doi-access=free|bibcode=2020ArtSD..5900991S }}</ref> and [[Eoprosopon|''Eoprosopon klugi'']] from the late Pliensbachian of Germany, which may belong to the living family [[Homolodromiidae]].<ref>{{Cite journal|last1=Schweitzer|first1=Carrie E.|last2=Feldmann|first2=Rodney M.|date=2010-05-01|title=The Oldest Brachyura (Decapoda: Homolodromioidea: Glaessneropsoidea) Known to Date (Jurassic)|journal=Journal of Crustacean Biology|volume=30|issue=2|pages=251–256|doi=10.1651/09-3231.1|s2cid=84707572|issn=0278-0372|doi-access=free|bibcode=2010JCBio..30..251F }}</ref> Most Jurassic crabs are known only from [[carapace]] pieces, which makes it difficult to determine their relationships.<ref name="Guinot-2019">{{Cite journal|last=Guinot|first=Danièle|date=2019-11-14|title=New hypotheses concerning the earliest brachyurans (Crustacea, Decapoda, Brachyura)|journal=Geodiversitas|volume=41|issue=1|page=747|doi=10.5252/geodiversitas2019v41a22|s2cid=214220075|issn=1280-9659|doi-access=free|bibcode=2019Geodv..41..747G }}</ref> While rare in the Early and Middle Jurassic, crabs became abundant during the Late Jurassic as they expanded from their ancestral silty sea floor habitat into hard substrate habitats like reefs, with crevices in reefs providing refuge from predators.<ref name="Guinot-2019" /><ref name="Klompmaker-2013" /> [[Hermit crab]]s also first appeared during the Jurassic, with the earliest known being ''[[Schobertella|Schobertella hoelderi]]'' from the late Hettangian of Germany.<ref>{{Cite journal|last1=Fraaije|first1=René|last2=Schweigert|first2=Günter|last3=Nützel|first3=Alexander|last4=Havlik|first4=Philipe|date=2013-01-01|title=New Early Jurassic hermit crabs from Germany and France|journal=Journal of Crustacean Biology|language=en|volume=33|issue=6|pages=802–817|doi=10.1163/1937240X-00002191|issn=0278-0372|doi-access=free|bibcode=2013JCBio..33..802F }}</ref> Early hermit crabs are associated with ammonite shells rather than those of gastropods.<ref>{{Cite journal|last=Mironenko|first=Aleksandr|date=January 2020|title=A hermit crab preserved inside an ammonite shell from the Upper Jurassic of central Russia: Implications to ammonoid palaeoecology|journal=Palaeogeography, Palaeoclimatology, Palaeoecology|language=en|volume=537|article-number=109397|doi=10.1016/j.palaeo.2019.109397|bibcode=2020PPP...53709397M|doi-access=free}}</ref> [[Glypheidea|Glypheids]], which today are only known from two species, reached their peak diversity during the Jurassic, with around 150 species out of a total fossil record of 250 known from the period.<ref>{{Cite journal|last1=Bracken-Grissom|first1=Heather D.|last2=Ahyong|first2=Shane T.|last3=Wilkinson|first3=Richard D.|last4=Feldmann|first4=Rodney M.|last5=Schweitzer|first5=Carrie E.|last6=Breinholt|first6=Jesse W.|last7=Bendall|first7=Matthew|last8=Palero|first8=Ferran|last9=Chan|first9=Tin-Yam|last10=Felder|first10=Darryl L.|last11=Robles|first11=Rafael|date=2014-07-01|title=The Emergence of Lobsters: Phylogenetic Relationships, Morphological Evolution and Divergence Time Comparisons of an Ancient Group (Decapoda: Achelata, Astacidea, Glypheidea, Polychelida)|url=https://academic.oup.com/sysbio/article/63/4/457/2847939|journal=Systematic Biology|language=en|volume=63|issue=4|pages=457–479|doi=10.1093/sysbio/syu008|pmid=24562813|issn=1063-5157|doi-access=free|url-access=subscription}}</ref> Jurassic barnacles were of low diversity compared to present,<ref>{{Cite journal|last1=Chan|first1=Benny K K|last2=Dreyer|first2=Niklas|last3=Gale|first3=Andy S|last4=Glenner|first4=Henrik|last5=Ewers-Saucedo|first5=Christine|last6=Pérez-Losada|first6=Marcos|last7=Kolbasov|first7=Gregory A|last8=Crandall|first8=Keith A|last9=Høeg|first9=Jens T|date=2021-02-25|title=The evolutionary diversity of barnacles, with an updated classification of fossil and living forms|journal=Zoological Journal of the Linnean Society|volume=193|issue=3|pages=789–846|doi=10.1093/zoolinnean/zlaa160|issn=0024-4082|doi-access=free|hdl=11250/2990967|hdl-access=free}}</ref> but several important evolutionary innovations are known, including the first appearances of calcite shelled forms and species with an epiplanktonic mode of life.<ref>{{Cite journal|last1=Gale|first1=Andy|last2=Schweigert|first2=Günter|date=January 2016|editor-last=Hautmann|editor-first=Michael|title=A new phosphatic-shelled cirripede (Crustacea, Thoracica) from the Lower Jurassic (Toarcian) of Germany – the oldest epiplanktonic barnacle|journal=Palaeontology|language=en|volume=59|issue=1|pages=59–70|doi=10.1111/pala.12207|bibcode=2016Palgy..59...59G |s2cid=128383968 |doi-access=free}}</ref>

==== Brachiopods ====
[[Brachiopod]] diversity declined during the Triassic–Jurassic extinction. Spire-bearing brachiopods ([[Spiriferinida]] and [[Athyridida]]) did not recover their biodiversity, becoming extinct in the TOAE.<ref name="Vörös-2016">{{Cite journal|last1=Vörös|first1=Attila|last2=Kocsis|first2=Ádám T.|last3=Pálfy|first3=József|date=September 2016|title=Demise of the last two spire-bearing brachiopod orders (Spiriferinida and Athyridida) at the Toarcian (Early Jurassic) extinction event|url=https://linkinghub.elsevier.com/retrieve/pii/S0031018216302140|journal=Palaeogeography, Palaeoclimatology, Palaeoecology|language=en|volume=457|pages=233–241|bibcode=2016PPP...457..233V|doi=10.1016/j.palaeo.2016.06.022}}</ref> [[Rhynchonellida]] and [[Terebratulida]] also declined during the Triassic–Jurassic extinction but rebounded during the Early Jurassic; neither clade underwent much morphological variation.<ref>{{Cite journal|last1=Vörös|first1=Attila|last2=Kocsis|first2=Ádám T.|last3=Pálfy|first3=József|date=2019|title=Mass extinctions and clade extinctions in the history of brachiopods: Brief review and a post-Paleozoic case study|url=https://riviste.unimi.it/index.php/RIPS/article/view/12184|journal=Rivista Italiana di Paleontologia e Stratigrafia|language=en|volume=125|issue=3|doi=10.13130/2039-4942/12184|issn=2039-4942|access-date=2020-12-25|archive-date=2020-09-01|archive-url=https://web.archive.org/web/20200901035135/https://riviste.unimi.it/index.php/RIPS/article/view/12184}}</ref> Brachiopods substantially declined in the Late Jurassic; the causes are poorly understood. Proposed reasons include increased predation, competition with bivalves, enhanced [[bioturbation]] or increased [[grazing pressure]].<ref>{{Cite journal|last1=Manojlovic|first1=Marko|last2=Clapham|first2=Matthew E.|date=2020-11-23|title=The role of bioturbation-driven substrate disturbance in the Mesozoic brachiopod decline|journal=Paleobiology|volume=47|language=en|pages=86–100|doi=10.1017/pab.2020.50|issn=0094-8373|doi-access=free}}</ref>

==== Bryozoans ====
Like the preceding Triassic, [[bryozoa]]n diversity was relatively low compared to the Paleozoic. The vast majority of Jurassic bryozoans are members of [[Cyclostomatida]], which experienced a radiation during the Middle Jurassic, with all Jurassic representatives belonging to the suborders [[Tubuliporina]] and [[List of Cyclostomatida families|Cerioporina]]. [[Cheilostomata]], the dominant group of modern bryozoans, first appeared during the Late Jurassic.<ref>{{Cite journal|last1=Taylor|first1=Paul D.|last2=Ernst|first2=Andrej|date=June 2008|title=Bryozoans in transition: The depauperate and patchy Jurassic biota|url=https://linkinghub.elsevier.com/retrieve/pii/S0031018208001491|journal=Palaeogeography, Palaeoclimatology, Palaeoecology|language=en|volume=263|issue=1–2|pages=9–23|doi=10.1016/j.palaeo.2008.01.028|bibcode=2008PPP...263....9T |url-access=subscription}}</ref>

==== Molluscs ====
===== Gastropods =====
Marine gastropods were significantly affected by the T-J extinction, with around 56% of genera going extinct, with [[Neritimorpha]] being particularly strongly effected, while [[Heterobranchia]] suffered much lower losses than other groups.<ref>{{Cite journal |last1=Ferrari |first1=Mariel |last2=Hautmann |first2=Michael |date=2022-11-02 |editor-last=Kiel |editor-first=Steffen |title=Gastropods underwent a major taxonomic turnover during the end-Triassic marine mass extinction event |journal=PLOS ONE |language=en |volume=17 |issue=11 |article-number=e0276329 |doi=10.1371/journal.pone.0276329 |doi-access=free |issn=1932-6203 |pmc=9629647 |pmid=36322518|bibcode=2022PLoSO..1776329F }}</ref> While present, the diversity of [[Freshwater snail|freshwater]] and [[land snail]]s was much lower during the Jurassic than in contemporary ecosystems, with the diversity of these groups not reaching levels comparable to modern times until the following Cretaceous.<ref>{{Cite journal |last=Neubauer |first=Thomas A. |date=February 2024 |title=The fossil record of freshwater Gastropoda – a global review |journal=Biological Reviews |language=en |volume=99 |issue=1 |pages=177–199 |doi=10.1111/brv.13016 |issn=1464-7931|doi-access=free |pmid=37698140 }}</ref>

===== Bivalves =====
The end-Triassic extinction had a severe impact on bivalve diversity, though it had little impact on bivalve ecological diversity. The extinction was selective, having less of an impact on deep burrowers, but there is no evidence of a differential impact between surface-living (epifaunal) and burrowing (infaunal) bivalves.<ref>{{Cite journal|last1=Ros|first1=Sonia|last2=De Renzi|first2=Miquel|last3=Damborenea|first3=Susana E.|last4=Márquez-Aliaga|first4=Ana|date=November 2011|title=Coping between crises: Early Triassic–early Jurassic bivalve diversity dynamics|url=https://linkinghub.elsevier.com/retrieve/pii/S0031018211004573|journal=Palaeogeography, Palaeoclimatology, Palaeoecology|language=en|volume=311|issue=3–4|pages=184–199|doi=10.1016/j.palaeo.2011.08.020|bibcode=2011PPP...311..184R|hdl=11336/81358 |hdl-access=free}}</ref> Bivalve family level diversity after the Early Jurassic was static, though genus diversity experienced a gradual increase throughout the period.<ref>{{Cite journal|last1=Mondal|first1=Subhronil|last2=Harries|first2=Peter J.|date=February 2016|title=The Effect of Taxonomic Corrections on Phanerozoic Generic Richness Trends in Marine Bivalves with a Discussion on the Clade's Overall History|url=https://www.cambridge.org/core/product/identifier/S0094837315000354/type/journal_article|journal=Paleobiology|language=en|volume=42|issue=1|pages=157–171|doi=10.1017/pab.2015.35|bibcode=2016Pbio...42..157M |s2cid=87260961|issn=0094-8373|url-access=subscription}}</ref> [[Rudists]], the dominant reef-building organisms of the Cretaceous, first appeared in the Late Jurassic (mid-Oxfordian) in the northern margin of the western Tethys, expanding to the eastern Tethys by the end of the Jurassic.<ref>{{Cite journal|last1=Sha|first1=J.|last2=Cestari|first2=R.|last3=Fabbi|first3=S.|date=April 2020|title=Paleobiogeographic distribution of rudist bivalves (Hippuritida) in the Oxfordian–early Aptian (Late Jurassic–Early Cretaceous)|url=https://linkinghub.elsevier.com/retrieve/pii/S0195667119302782|journal=Cretaceous Research|language=en|volume=108|article-number=104289|doi=10.1016/j.cretres.2019.104289|bibcode=2020CrRes.10804289S |s2cid=210248232|url-access=subscription}}</ref>

===== Cephalopods =====
[[File:Proteroctopus ribeti.jpg|thumb|Fossil specimen of ''[[Proteroctopus]]'' from the Middle Jurassic of France, formerly thought to be world's oldest known octopus]]Ammonites were devastated by the end-Triassic extinction, with only a handful of genera belonging to the family [[Psiloceratidae]] of the suborder [[Phylloceratina]] surviving and becoming ancestral to all later Jurassic and Cretaceous ammonites. Ammonites explosively diversified during the Early Jurassic, with the orders [[Psiloceratina]], [[Ammonitina]], [[Lytoceratina]], [[Haploceratoidea|Haploceratina]], [[Perisphinctoidea|Perisphinctina]] and [[Ancyloceratina]] all appearing during the Jurassic. Ammonite faunas during the Jurassic were regional, being divided into around 20 distinguishable provinces and subprovinces in two realms, the northern high latitude Pan-Boreal realm, consisting of the Arctic, northern Panthalassa and northern Atlantic regions, and the equatorial–southern Pan-Tethyan realm, which included the Tethys and most of Panthalassa.<ref>{{Cite journal |last=Page |first=Kevin N. |date=January 2008 |title=The evolution and geography of Jurassic ammonoids |url=https://linkinghub.elsevier.com/retrieve/pii/S001678780880257X |journal=Proceedings of the Geologists' Association |language=en |volume=119 |issue=1 |pages=35–57 |doi=10.1016/S0016-7878(08)80257-X|bibcode=2008PrGA..119...35P |url-access=subscription }}</ref> Ammonite diversifications occurred coevally with [[marine transgression]]s, while their diversity nadirs occurred during [[marine regression]]s.<ref>{{cite journal |last1=Sandoval |first1=José |last2=O'Dogherty |first2=Jean |last3=Guex |first3=Jean |date=1 August 2001 |title=Evolutionary Rates of Jurassic Ammonites in Relation to Sea-level Fluctuations |url=https://pubs.geoscienceworld.org/sepm/palaios/article-abstract/16/4/311/114327/Evolutionary-Rates-of-Jurassic-Ammonites-in |journal=[[PALAIOS]] |volume=16 |issue=4 |pages=311–335 |doi=10.1669/0883-1351(2001)016<0311:EROJAI>2.0.CO;2 |bibcode=2001Palai..16..311S |s2cid=129982065 |access-date=26 August 2023|url-access=subscription }}</ref>

The oldest definitive records of the squid-like [[Belemnitida|belemnites]] are from the earliest Jurassic (Hettangian–Sinemurian) of Europe and Japan; they expanded worldwide during the Jurassic.<ref>{{Cite journal|last1=Iba|first1=Yasuhiro|last2=Sano|first2=Shin-ichi|last3=Mutterlose|first3=Jörg|date=2014-05-02|editor-last=Samonds|editor-first=Karen E.|title=The Early Evolutionary History of Belemnites: New Data from Japan|journal=[[PLOS ONE]]|language=en|volume=9|issue=5|article-number=e95632|doi=10.1371/journal.pone.0095632|issn=1932-6203|pmc=4008418|pmid=24788872|bibcode=2014PLoSO...995632I|doi-access=free}}</ref> Belemnites were shallow-water dwellers, inhabiting the upper 200 metres of the water column on the [[Continental shelf|continental shelves]] and in the [[littoral zone]]. They were key components of Jurassic ecosystems, both as predators and prey, as evidenced by the abundance of belemnite guards in Jurassic rocks.<ref>{{Cite journal|last1=Hoffmann|first1=René|last2=Stevens|first2=Kevin|date=February 2020|title=The palaeobiology of belemnites – foundation for the interpretation of rostrum geochemistry|journal=Biological Reviews|language=en|volume=95|issue=1|pages=94–123|doi=10.1111/brv.12557|pmid=31729839|s2cid=208036104|issn=1464-7931|doi-access=free}}</ref>

The earliest [[Vampyromorphida|vampyromorphs]], of which the only living member is the [[vampire squid]], first appeared during the Early Jurassic.<ref>{{Cite journal|last1=Fuchs|first1=Dirk|last2=Weis|first2=Robert|date=2008-07-11|title=Taxonomy, morphology and phylogeny of Lower Jurassic loligosepiid coleoids (Cephalopoda)|url=http://www.schweizerbart.de/papers/njgpa/detail/249/59331/Taxonomy_morphology_and_phylogeny_of_Lower_Jurassi?af=crossref|journal=Neues Jahrbuch für Geologie und Paläontologie – Abhandlungen|language=en|volume=249|issue=1|pages=93–112|doi=10.1127/0077-7749/2008/0249-0093|bibcode=2008NJGPA.249...93F |issn=0077-7749|url-access=subscription}}</ref> The earliest [[octopus]]es appeared during the Middle Jurassic, having split from their closest living relatives, the vampyromorphs, during the Triassic to Early Jurassic.<ref name="Fuchs-2020">{{Cite journal |last1=Fuchs |first1=Dirk |last2=Iba |first2=Yasuhiro |last3=Heyng |first3=Alexander |last4=Iijima |first4=Masaya |last5=Klug |first5=Christian |last6=Larson |first6=Neal L. |last7=Schweigert |first7=Günter |date=February 2020 |editor-last=Brayard |editor-first=Arnaud |title=The Muensterelloidea: phylogeny and character evolution of Mesozoic stem octopods |url=https://onlinelibrary.wiley.com/doi/10.1002/spp2.1254 |journal=Papers in Palaeontology |language=en |volume=6 |issue=1 |pages=31–92 |doi=10.1002/spp2.1254 |bibcode=2020PPal....6...31F |issn=2056-2802 |s2cid=198256507|url-access=subscription }}</ref> All Jurassic octopuses are solely known from the hard [[Gladius (cephalopod)|gladius]].<ref name="Fuchs-2020" /><ref>{{Cite journal|last1=Fuchs|first1=Dirk|last2=Schweigert|first2=Günter|date=June 2018|title=First Middle–Late Jurassic gladius vestiges provide new evidence on the detailed origin of incirrate and cirrate octopuses (Coleoidea)|url=http://link.springer.com/10.1007/s12542-017-0399-8|journal=PalZ|language=en|volume=92|issue=2|pages=203–217|doi=10.1007/s12542-017-0399-8|bibcode=2018PalZ...92..203F |issn=0031-0220|s2cid=135245479|url-access=subscription}}</ref> Octopuses likely originated from bottom-dwelling ([[Benthic zone|benthic]]) ancestors which lived in shallow environments.<ref name="Fuchs-2020" /> ''[[Proteroctopus]]'' from the late Middle Jurassic [[La Voulte-sur-Rhône (lagerstätte)|La Voulte-sur-Rhône lagerstätte]], previously interpreted as an early octopus, is now thought to be a basal taxon outside the clade containing vampyromorphs and octopuses.<ref>{{Cite journal|last1=Kruta|first1=Isabelle|last2=Rouget|first2=Isabelle|last3=Charbonnier|first3=Sylvain|last4=Bardin|first4=Jérémie|last5=Fernandez|first5=Vincent|last6=Germain|first6=Damien|last7=Brayard|first7=Arnaud|last8=Landman|first8=Neil|date=2016|title=Proteroctopus ribeti in coleoid evolution|journal=[[Palaeontology (journal)|Palaeontology]]|language=en|volume=59|issue=6|pages=767–773|doi=10.1111/pala.12265|bibcode=2016Palgy..59..767K |s2cid=132420410 |issn=1475-4983|doi-access=free}}</ref>

==References==
{{Reflist|group=note}}

===Citations===
{{reflist}}

==External links==
* [http://www.geo-lieven.com/erdzeitalter/jura/jura.htm Examples of Jurassic Fossils]
* [https://ghkclass.com/ghkC.html?jurassic Jurassic (chronostratigraphy scale)]
* [https://web.archive.org/web/20081208011604/http://harbury.villagebuzz.co.uk/viewtopic.php?f=16&t=297 Jurassic fossils in Harbury, Warwickshire]
* [http://www.foraminifera.eu/querydb.php?period=Jurassic&aktion=suche Jurassic Microfossils: 65+ images of Foraminifera]
* {{cite EB1911|wstitle=Jurassic|volume=15|short=1}} With map and table.

{{subject bar|Geology|Paleontology|wikt=y|auto=1}}
{{Jurassic Footer}}
{{Geological history|p|m|state=collapsed}}

{{Authority control}}

[[Category:Jurassic| ]]
[[Category:Geological periods]]