Argentinosaurus
Template:Short description Template:Use American English Template:Use mdy dates Template:Automatic taxobox
Argentinosaurus (meaning "lizard from Argentina") is a genus of giant sauropod dinosaur that lived during the Late Cretaceous period in what is now Argentina. Although it is only known from fragmentary remains, Argentinosaurus is one of the largest known land animals of all time, perhaps the largest, measuring Template:Cvt long and weighing Template:Cvt. It was a member of Titanosauria, the dominant group of sauropods during the Cretaceous.
The first Argentinosaurus bone was discovered in 1987 by a farmer on his farm near the city of Plaza Huincul. A scientific excavation of the site led by the Argentine palaeontologist José Bonaparte was conducted in 1989, yielding several back vertebrae and parts of a sacrum—fused vertebrae between the back and tail vertebrae. Additional specimens include a complete femur (thigh bone) and the shaft of another. Argentinosaurus was named by Bonaparte and the Argentine palaeontologist Rodolfo Coria in 1993; the genus contains a single species, A. huinculensis, after its place of discovery, Plaza Huincul.
The fragmentary nature of Argentinosaurus remains makes their interpretation difficult. Arguments revolve around the position of the recovered vertebrae within the vertebral column and the presence of accessory articulations between the vertebrae that would have strengthened the spine. A computer model of the skeleton and muscles estimated this dinosaur had a maximum speed of 7.2 km/h (5 mph) with a pace, a gait where the fore and hind limb of the same side of the body move simultaneously. The fossils of Argentinosaurus were recovered from the Huincul Formation, which was deposited in the middle Cenomanian to early Turonian ages (about 97 to 93.5 million years ago<ref name="Holtz2011" />) and contains a diverse dinosaur fauna including the giant theropod Mapusaurus.
Discovery
The first Argentinosaurus bone, which is now thought to be a fibula (calf bone), was discovered in 1987 by Guillermo Heredia on his farm "Las Overas" about Template:Cvt east of Plaza Huincul, in Neuquén Province, Argentina. Heredia, initially believing he had discovered petrified logs, informed the local museum, the Museo Carmen Funes, whose staff members excavated the bone and stored it in the museum's exhibition room. In early 1989, the Argentine palaeontologist José F. Bonaparte initiated a larger excavation of the site involving palaeontologists of the Museo Argentino de Ciencias Naturales, yielding a number of additional elements from the same individual. The individual, which later became the holotype of Argentinosaurus huinculensis, is catalogued under the specimen number MCF-PVPH 1.<ref name="salgado2010"/>
Separating fossils from the very hard rock in which the bones were encased required the use of pneumatic hammers.<ref name="Bonaparte1993"/><ref name="lmneuquen">Template:Cite web</ref><ref name="prothero2016">Template:Cite book</ref>Template:Rp The additional material recovered included seven dorsal vertebrae (vertebrae of the back),<ref name="salgado2010">Template:Cite journal</ref> the underside of the sacrum (fused vertebrae between the dorsal and tail vertebrae) including the first to fifth Template:Dinogloss and some sacral ribs, and a part of a dorsal rib (rib from the flank).<ref name="Bonaparte1993"/> These finds were also incorporated into the collection of the Museo Carmen Funes.<ref name="Bonaparte1993"/>
Bonaparte presented the new find in 1989 at a scientific conference in San Juan. The formal description was published in 1993 by Bonaparte and the Argentine palaeontologist Rodolfo Coria, with the naming of a new genus and species, Argentinosaurus huinculensis. The generic name means "Argentine lizard", while the specific name refers to the town Plaza Huincul.<ref name="Bonaparte1993">Template:Cite journal</ref> Bonaparte and Coria described the limb bone discovered in 1987 as an eroded tibia (shin bone), although the Uruguayan palaeontologist Gerardo Mazzetta and colleagues reidentified this bone as a left fibula in 2004.<ref name="Mazzettaetal2004">Template:Cite journal</ref><ref name="salgado2007"/> In 1996, Bonaparte referred (assigned) a complete femur (thigh bone) from the same locality to the genus, which was put on exhibit at the Museo Carmen Funes. This bone was deformed by front-to-back crushing during fossilization. In their 2004 study, Mazzetta and colleagues mentioned an additional femur that is housed in the La Plata Museum under the specimen number MLP-DP 46-VIII-21-3. Though not as strongly deformed as the complete femur, it preserves only the shaft and lacks its upper and lower ends. Both specimens belonged to individuals equivalent in size to the holotype individual.<ref name="Mazzettaetal2004"/> As of 2019, however, it was still uncertain whether any of these femora belonged to Argentinosaurus.<ref name="Paul2019"/>
Description
Size
Argentinosaurus is among the largest known land animals, although its exact size is difficult to estimate because of the incompleteness of its remains.<ref name="Carballido-2017" /> To counter this problem, palaeontologists can compare the known material with that of smaller related sauropods known from more complete remains. The more complete taxon can then be scaled up to match the dimensions of Argentinosaurus. Mass can be estimated from known relationships between certain bone measurements and body mass, or through determining the volume of models.<ref name="Paul1997">Template:Cite conference</ref>
A reconstruction of Argentinosaurus created by Gregory Paul in 1994 yielded a length estimate of Template:Convert.<ref name="Paul1994">Template:Cite journal</ref> Later that year, estimates by Bonaparte and Coria suggesting a hind limb length of Template:Convert, a trunk length (hip to shoulder) of Template:Convert, and an overall body length of Template:Convert were published.<ref name="Appenzeller1994">Template:Cite journal</ref> In 2006, Kenneth Carpenter reconstructed Argentinosaurus using the more complete Saltasaurus as a guide and estimated a length of Template:Convert.<ref name="Carpenter2006">Template:Cite journal</ref> In 2008, Jorge Calvo and colleagues used the proportions of Futalognkosaurus to estimate the length of Argentinosaurus at less than Template:Cvt.<ref name="Calvo2008">Template:Cite journal</ref> In 2013, William Sellers and colleagues arrived at a length estimate of Template:Convert and a shoulder height of Template:Convert by measuring the skeletal mount in Museo Carmen Funes.<ref name="plosone" /> During the same year, Scott Hartman suggested that because Argentinosaurus was then thought to be a basal titanosaur, it would have a shorter tail and narrower chest than Puertasaurus, which he estimated to be about Template:Convert long, indicating Argentinosaurus was slightly smaller.<ref name="Hartman 2013">Template:Cite web</ref> In 2016, Paul estimated the length of Argentinosaurus at Template:Cvt,<ref name="Paul2016">Template:Cite book</ref> but later estimated a greater length of Template:Convert or longer in 2019, restoring the unknown neck and tail of Argentinosaurus after those of other large South American titanosaurs.<ref name="Paul2019">Template:Cite journal</ref>
Paul estimated a body mass of Template:Convert for Argentinosaurus in 1994.<ref name="Paul1994" /> In 2004, Mazzetta and colleagues provided a range of Template:Convert and considered Template:Convert to be the most likely mass, making it the heaviest sauropod known from good material.<ref name="Mazzettaetal2004"/> In 2013, Sellers and colleagues estimated a mass of Template:Convert by calculating the volume of the aforementioned Museo Carmen Funes skeleton.<ref name="plosone">Template:Cite journal</ref> In 2014 and 2018, Roger Benson and colleagues estimated the mass of Argentinosaurus at Template:Convert,<ref name="Bensonetal2014">Template:Cite journal</ref><ref>Template:Cite journal</ref> but these estimates were questioned due to a very large error range and lack of precision.<ref name=Campione&Evans2020>Template:Cite journal</ref> In 2016, using equations that estimate body mass based on the circumference of the humerus and femur of quadrupedal animals, Bernardo Gonzáles Riga and colleagues estimated a mass of Template:Convert based on an isolated femur; it is uncertain whether this femur actually belongs to Argentinosaurus.<ref name="Riga2016">Template:Cite journal</ref> In the same year, Paul moderated his earlier estimate from 1994 and listed the body mass of Argentinosaurus at more than Template:Convert.<ref name="Paul2016" /> In 2019, Paul moderated his 2016 estimate and gave a mass estimate of Template:Convert based on his skeletal reconstructions (diagrams illustrating the bones and shape of an animal) of Argentinosaurus in dorsal and lateral view.<ref name="Paul2019" /> In 2020, Campione and Evans also yielded a body mass estimate of approximately Template:Convert.<ref name=Campione&Evans2020/> In 2023, Paul and Larramendi proposed that the holotype would have weighed between Template:Convert at maximum. They further suggested that the enigmatic, fragmentary Bruhathkayosaurus possibly weighed more, between Template:Convert.<ref name=Bruhathkayosaurus2023>Template:Cite journal</ref>
While Argentinosaurus was definitely a massive animal, there is disagreement over whether it was the largest known titanosaur. Puertasaurus, Futalognkosaurus, Dreadnoughtus, Paralititan, "Antarctosaurus" giganteus, and Alamosaurus have all been considered to be comparable in size with Argentinosaurus by some studies,<ref name=Lacovara2014>Template:Cite journal</ref><ref name="Fowler2011">Template:Cite journal</ref> although others have found them to be notably smaller.<ref name="Calvo2008"/><ref name=Bates2015>Template:Cite journal</ref><ref name="Paul2019" /> In 2017, Carballido and colleagues considered Argentinosaurus to be smaller than Patagotitan, since the latter had a greater area enclosed by the Template:Dinogloss, Template:Dinogloss, and Template:Dinogloss of its anterior dorsal vertebrae.<ref name="Carballido-2017" /> However, Paul found Patagotitan to be smaller than Argentinosaurus in 2019, due to the latter's dorsal column being considerably longer. Even if Argentinosaurus was the largest-known titanosaur, other sauropods including Maraapunisaurus and a giant mamenchisaurid, may have been larger, although these are only known from very scant remains. Some diplodocids, such as Supersaurus and Diplodocus<ref name="Tschopp2015">Template:Cite journal</ref><ref name="Paul2019" /> may have exceeded Argentinosaurus in length despite being considerably less massive.<ref name="Carpenter2006" /><ref name="Lovelace2007">Template:Cite journal</ref> The mass of the blue whale, however, which can be greater than Template:Convert,<ref>Template:Cite web</ref><ref name="Whale">Template:Cite journal</ref> still exceeds that of all known sauropods.<ref name="Paul2019" />
Vertebrae
Argentinosaurus likely possessed 10 dorsal vertebrae, like other titanosaurs.<ref name="Paul2019" /> The vertebrae were enormous even for sauropods; one dorsal vertebra has a reconstructed height of Template:Convert and a width of Template:Convert, and the Template:Dinogloss are up to Template:Convert in width.<ref name="Bonaparte1993"/> In 2019, Paul estimated the total length of the dorsal vertebral column at Template:Convert and the width of the pelvis at 0.6 times the combined length of the dorsal and sacral vertebral column.<ref name="Paul2019" /> The dorsals were Template:Dinogloss (concave at the rear) as in other macronarian sauropods.<ref name="Bonaparte1993"/><ref name="salgado2007">Template:Cite book</ref>Template:Rp The Template:Dinogloss (excavations on the sides of the centra) were proportionally small and positioned in the front half of the centrum.<ref name="bonaparte1996">Template:Cite journal</ref>Template:Rp The vertebrae were internally lightened by a complex pattern of numerous air-filled chambers. Such camellate bone is, among sauropods, especially pronounced in the largest and longest-necked species.<ref name="novas2009"/><ref name="wedel2005">Template:Cite book</ref> In both the dorsal and sacral vertebrae, very large cavities measuring Template:Convert were present.<ref name="novas2009">Template:Cite book</ref> The dorsal ribs were tubular and cylindrical in shape, in contrast with other titanosaurs.<ref name="Bonaparte1993"/><ref name="upchurch2004"/>Template:Rp Bonaparte and Coria, in their 1993 description, noted the ribs were hollow, unlike those of many other sauropods, but later authors argued this hollowing could also have been due to erosion after the death of the individual.<ref name="salgado2007"/> Argentinosaurus, like many titanosaurs,<ref name="Overosaurus">Template:Cite journal</ref> probably had six sacral vertebrae (those in the hip region), although the last one is not preserved. The centra of the second to fifth sacral vertebrae were much reduced in size and considerably smaller than the centrum of the first sacral. The sacral ribs curved downwards. The second sacral rib was larger than the other preserved sacral ribs, though the size of the first is unknown due to its incompleteness.<ref name="Bonaparte1993"/>
Because of their incomplete preservation, the original position of the known dorsal vertebrae within the vertebral column is disputed. Dissenting configurations were suggested by Bonaparte and Coria in 1993; Fernando Novas and Martín Ezcurra in 2006; and Leonardo Salgado and Jaime Powell in 2010. One vertebra was interpreted by these studies as the first, fifth or third; and another vertebra as the second, tenth or eleventh, or ninth, respectively. A reasonably complete vertebra was found to be the third by the 1993 and 2006 studies, but the fourth by the 2010 study. Another vertebra was interpreted by the three studies as being part of the rear section of the dorsal vertebral column, as the fourth, or as the fifth, respectively. In 1993, two articulated (still connected) vertebrae were thought to be of the rear part of the dorsal column but are interpreted as the sixth and seventh vertebrae in the two later studies. The 2010 study mentioned another vertebra that was not mentioned by the 1993 and 2006 studies; it was presumed to belong to the rear part of the dorsal column.<ref name="Bonaparte1993"/><ref name="novas_ezcurra_2006">Template:Cite journal</ref><ref name="salgado2010"/>
Another contentious issue is the presence of hyposphene-hypantrum articulations, accessory joints between vertebrae that were located below the main articular processes. Difficulties in interpretation arise from the fragmentary preservation of the vertebral column; these joints are hidden from view in the two connected vertebrae.<ref name="novas2009"/> In 1993, Bonaparte and Coria said the hyposphene-hypantrum articulations were enlarged, as in the related Epachthosaurus, and had additional articular surfaces that extended downwards.<ref name="Bonaparte1993"/> This was confirmed by some later authors; Novas noted the hypantrum (a bony extension below the articular processes of the front face of a vertebra) extended sidewards and downwards, forming a much-broadened surface that connected with the equally enlarged hyposphene at the back face of the following vertebra.<ref name="novas2009"/><ref name="upchurch2004"/>Template:Rp In 1996, Bonaparte stated these features would have made the spine more rigid and were possibly an adaptation to the giant size of the animal.<ref name="bonaparte1996"/> Other authors argued most titanosaur genera lacked hyposphene-hypantrum articulations and that the articular structures seen in Epachthosaurus and Argentinosaurus are thickened vertebral Template:Dinogloss (ridges).<ref name="novas2009"/><ref name="sanz1999">Template:Cite journal</ref><ref name="powell2003">Template:Cite book</ref>Template:Rp Sebastián Apesteguía, in 2005, argued the structures seen in Argentinosaurus, which he termed hyposphenal bars, are indeed thickened laminae that could have been derived from the original hyposphene and had the same function.<ref name="apesteguia2005">Template:Cite book</ref>
Limbs
.jpg){kind=link}
The complete femur that was assigned to Argentinosaurus is Template:Convert long. The femoral shaft has a circumference of about Template:Convert at its narrowest part. Mazzetta and colleagues used regression equations to estimate its original length at Template:Convert, which is similar to the length of the other femur, and later in 2019 Paul gave a similar estimate of Template:Convert.<ref name="Paul2019" /> By comparison, the complete femora preserved in the other giant titanosaurs Antarctosaurus giganteus and Patagotitan mayorum measure Template:Convert and Template:Convert, respectively.<ref name="Mazzettaetal2004" /><ref name="Carballido-2017" /> While the holotype specimen does not preserve a femur, it preserves a slender fibula (originally interpreted as a tibia) that is Template:Convert in length. When it was identified as a tibia, it was thought to have a comparatively short Template:Dinogloss, a prominent extension at the upper front that anchored muscles for stretching the leg. However, as stated by Mazzetta and colleagues, this bone lacks both the proportions and anatomical details of a tibia, while being similar in shape to other sauropod fibulae.<ref name="Bonaparte1993"/><ref name="Mazzettaetal2004" />
Classification
Relationships within Titanosauria are amongst the least understood of all groups of dinosaurs.<ref name="Wilson2006"/> Traditionally, the majority of sauropod fossils from the Cretaceous had been referred to a single family, the Titanosauridae, which has been in use since 1893.<ref name="Wilson2003"/> In their 1993 first description of Argentinosaurus, Bonaparte and Coria noted it differed from typical titanosaurids in having hyposphene-hypantrum articulations. As these articulations were also present in the titanosaurids Andesaurus and Epachthosaurus, Bonaparte and Coria proposed a separate family for the three genera, the Andesauridae. Both families were united into a new, higher group called Titanosauria.<ref name="Bonaparte1993"/>
In 1997, Salgado and colleagues found Argentinosaurus to belong to Titanosauridae in an unnamed clade with Opisthocoelicaudia and an indeterminate titanosaur.<ref name="Salgado1997">Template:Cite journal</ref> In 2002, Davide Pisani and colleagues recovered Argentinosaurus as a member of Titanosauria, and again found it to be in a clade with Opisthocoelicaudia and an unnamed taxon, in addition to Lirainosaurus.<ref name="Pisani2002">Template:Cite journal</ref> A 2003 study by Jeffrey Wilson and Paul Upchurch found both Titanosauridae and Andesauridae to be invalid; the Titanosauridae because it was based on the dubious genus Titanosaurus and the Andesauridae because it was defined on plesiomorphies (primitive features) rather than on synapomorphies (newly evolved features that distinguish the group from related groups).<ref name="Wilson2003">Template:Cite journal</ref> A 2011 study by Philip Mannion and Calvo found Andesauridae to be paraphyletic (excluding some of the group's descendants) and likewise recommended its disuse.<ref name="Mannion2011">Template:Cite journal</ref>
In 2004, Upchurch and colleagues introduced a new group called Lithostrotia that included the more derived (evolved) members of Titanosauria. Argentinosaurus was classified outside this group and thus as a more basal ("primitive") titanosaurian.<ref name="upchurch2004">Template:Cite book</ref>Template:Rp The basal position within Titanosauria was confirmed by a number of subsequent studies.<ref name="Wilson2006">Template:Cite journal</ref><ref name="novas2009"/><ref name="Filippi2011">Template:Cite journal</ref><ref name=Lacovara2014/><ref name="Riga2016"/> In 2007, Calvo and colleagues named Futalognkosaurus; they found it to form a clade with Mendozasaurus and named it Lognkosauria.<ref name="Calvo2007">Template:Cite journal</ref> A 2017 study by Carballido and colleagues recovered Argentinosaurus as a member of Lognkosauria and the sister taxon of Patagotitan.<ref name="Carballido-2017">Template:Cite journal</ref> In 2018, González Riga and colleagues also found it to belong in Lognkosauria, which in turn was found to belong to Lithostrotia.<ref name="Gonzalez Riga2018">Template:Cite journal</ref>
Another 2018 study by Hesham Sallam and colleagues found two different phylogenetic positions for Argentinosaurus based on two data sets. They did not recover it as a lognkosaurian but as either a basal titanosaur or a sister taxon of the more derived Epachthosaurus.<ref name="Sallam2019">Template:Cite journal</ref> In 2019, Julian Silva Junior and colleagues found Argentinosaurus to belong to Lognkosauria once again; they recovered Lognkosauria and Rinconsauria (another group generally included in Titanosauria) to be outside Titanosauria.<ref name="Silva Junior2019">Template:Cite journal</ref> Another 2019 study by González Riga and colleagues also found Argentinosaurus to belong to Lognkosauria; they found this group to form a larger clade with Rinconsauria within Titanosauria, which they named Colossosauria.<ref name="Gonzalez Riga2019">Template:Cite journal</ref>
Template:Col-begin Template:Col-break
Topology according to Carballido and colleagues, 2017.<ref name="Carballido-2017"/> Template:Clade Template:Col-break
Topology according to González Riga and colleagues, 2019.<ref name="Gonzalez Riga2019" /> Template:Clade
Palaeobiology
The giant size of Argentinosaurus and other sauropods was likely made possible by a combination of factors; these include fast and energy-efficient feeding allowed for by the long neck and lack of mastication, fast growth and fast population recovery due to their many small offspring. Advantages of giant sizes would likely have included the ability to keep food inside the digestive tract for lengthy periods to extract a maximum of energy, and increased protection against predators.<ref name="sander2011">Template:Cite journal</ref> Sauropods were oviparous (egg-laying). In 2016, Mark Hallett and Matthew Wedel stated that the eggs of Argentinosaurus were probably only Template:Convert in volume, and that a hatched Argentinosaurus was no longer than Template:Convert and not heavier than Template:Convert. The largest sauropods increased their size by five orders of magnitude after hatching, more than in any other amniote animals.<ref name="hallett2016"/>Template:Rp Hallett and Wedel estimated that Argentinosaurus reached sexual maturity at 8–10 years and physical maturity at 20 years, with a lifespan estimated at around 30 years.<ref name="hallett2016"/>Template:Rp Hallett and Wedel argued size increases in the evolution of sauropods were commonly followed by size increases of their predators, theropod dinosaurs. Argentinosaurus might have been preyed on by Mapusaurus, which is among the largest theropods known. Mapusaurus is known from at least seven individuals found together,<ref name="Mapusaurus"/> raising the possibility that this theropod hunted in packs to bring down large prey including Argentinosaurus.<ref name="hallett2016">Template:Citation</ref>Template:Rp
In 2013, Sellers and colleagues used a computer model of the skeleton and muscles of Argentinosaurus to study its speed and gait. Before computer simulations, the only way of estimating speeds of dinosaurs was through studying anatomy and trackways. The computer model was based on a laser scan of a mounted skeletal reconstruction on display at the Museo Carmen Funes. Muscles and their properties were based on comparisons with living animals; the final model had a mass of Template:Convert. Using computer simulation and machine learning techniques, which found a combination of movements that minimised energy requirements, the digital Argentinosaurus learned to walk. The optimal gait found by the algorithms was close to a pace (forelimb and hind limb on the same side of the body move simultaneously).<ref name="plosone" /> The model reached a top speed of just over 2 m/s (7.2 km/h, 5 mph).<ref>Template:Cite web</ref> The authors concluded with its giant size, Argentinosaurus reached a functional limit. Much larger terrestrial vertebrates might be possible but would require different body shapes and possibly behavioural change to prevent joint collapse. The authors of the study cautioned the model is not fully realistic and too simplistic, and that it could be improved in many areas. For further studies, more data from living animals is needed to improve the soft tissue reconstruction, and the model needs to be confirmed based on more complete sauropod specimens.<ref name="plosone" /> A 2025 study estimated that Argentinosaurus may have walked at a speed of Template:Convert.<ref name="scott2025">Template:Cite journal</ref>
Palaeoenvironment
Argentinosaurus was discovered in the Argentine Province of Neuquén. It was originally reported from the Huincul Group of the Río Limay Formation,<ref name="Bonaparte1993" /> which have since become known as the Huincul Formation and the Río Limay Subgroup, the latter of which is a subdivision of the Neuquén Group. This unit is located in the Neuquén Basin in Patagonia. The Huincul Formation is composed of yellowish and greenish sandstones of fine-to-medium grain, some of which are tuffaceous.<ref name="Leanza2004">Template:Cite journal</ref> These deposits were laid down during the Upper Cretaceous, either in the middle Cenomanian to early Turonian stages<ref name="Theropods" /> or the early Turonian to late Santonian.<ref name="Corbella2004">Template:Cite journal</ref> The deposits represent the drainage system of a braided river.<ref name="Rainoldi2015">Template:Cite journal</ref>
Fossilised pollen indicates a wide variety of plants were present in the Huincul Formation. A study of the El Zampal section of the formation found hornworts, liverworts, ferns, Selaginellales, possible Noeggerathiales, gymnosperms (including gnetophytes and conifers), and angiosperms (flowering plants), in addition to several pollen grains of unknown affinities.<ref name="Vallati2001">Template:Cite journal</ref> The Huincul Formation is among the richest Patagonian vertebrate associations, preserving fish including dipnoans and gar, chelid turtles, squamates, sphenodonts, neosuchian crocodilians, and a wide variety of dinosaurs.<ref name="Theropods" /><ref name="Vertebrates">Template:Cite journal</ref> Vertebrates are most commonly found in the lower, and therefore older, part of the formation.<ref name="Bellardini2018" />
In addition to Argentinosaurus, the sauropods of the Huincul Formation are represented by another titanosaur, Choconsaurus,<ref name="Choconsaurus">Template:Cite journal</ref> and several rebbachisaurids including Cathartesaura,<ref name="Diversity">Template:Cite journal</ref> Limaysaurus,<ref name="Calvo1995">Template:Cite journal</ref><ref name="Salgado2004">Template:Cite journal</ref> and some unnamed species.<ref name="Bellardini2018">Template:Cite journal</ref> Theropods including carcharodontosaurids such as Mapusaurus,<ref name="Mapusaurus">Template:Cite journal</ref> abelisaurids including Skorpiovenator,<ref name="Skorpiovenator">Template:Cite journal</ref> Ilokelesia, and Tralkasaurus,<ref name="Tralkasaurus">Template:Cite journal</ref> noasaurids such as Huinculsaurus,<ref name="Huinculsaurus">Template:Cite journal</ref> paravians such as Overoraptor,<ref name=Overoraptor>Template:Cite journal</ref> and other theropods such as Aoniraptor and Gualicho<ref name="Gualicho">Template:Cite journal</ref> have also been discovered there.<ref name="Theropods">Template:Cite journal</ref> Several iguanodonts are also present in the Huincul Formation.<ref name="Leanza2004" />