Tantulocarida

From Vero - Wikipedia
Jump to navigation Jump to search

Template:Short description Template:Automatic Taxobox

Tantulocarida is a highly specialised group of parasitic crustaceans that consists of about 33 species, treated as a class in superclass Multicrustacea. They are typically ectoparasites that infest copepods, isopods, tanaids, amphipods and ostracods.<ref>Template:Cite web</ref><ref>Template:Cite journal</ref>

Description

Template:Expand section

In the Tantulocarida, animals do not ever present eyes.<ref>Template:Cite journal</ref>

The tantulus larvae has a head with a ventral oral disc but no appendages, a six-segmented thorax with six pairs of legs, and a limbless abdomen consisting of one to six segments in addition to a telson.<ref>Multicellular Animals: Volume II: The Phylogenetic System of the Metazoa</ref> The larvae also possesses a cuticular stylet on the cephalon through which they can push a rootlet system for extraction of nutrients from a host. The rootlet system itself is a direct extension of the gut.<ref>Template:Cite journal</ref>

Template:AnchorBody length

Members of this subclass are minute – less than Template:Convert in length and have a dramatic reduction in body form compared to other crustaceans, with an unsegmented, sac-like thorax and a much reduced abdomen.<ref>Template:Cite encyclopedia</ref> One tantulocarid species, Tantulacus dieteri, is the world's smallest arthropod, with a total body length of only Template:Convert.<ref>Template:Cite journal</ref>

Life cycle

Template:Expand section The tantulocarid life cycle is unique among crustaceans. The tantulus larva transforms directly from a non-feeding (lecithotrophic) and free-swimming organism into a parasite without any instars. When entering the parasitic stage much of the body, such as the muscles, degenerates, even if the body itself becomes bigger. As a parasite it is permanently attached to its host, and after piercing its host's cuticle with an unpaired stylet, a rootlet system used to absorb nutrients enters through the hole and grow into the host's tissue. The adult form develops inside the larva, and can become either a sac-like parthenogenetic female, or a fully developed free-living, non-feeding and sexually-reproducing male or female.<ref>Template:Cite journal</ref><ref>Template:Cite journal</ref><ref>Itoitantulus misophricola gen. et sp. nov.: First Record of Tantulocarida (Crustacea: Maxillopoda) in the North Pacific Region</ref><ref>Template:Cite journal</ref><ref>Anatomy of the Tantulocarida: first results obtained using TEM and CLSM. Part I: tantulus larva - GfBS</ref> The eggs inside the parthenogenetic female are eventually released as fully developed tantulus larvae. The finding of what appears to be a benthic non-feeding nauplius larva suggests that eggs produced by sexual females hatch as nauplii instead of tantulus larvae. Both the parthenogenetic and sexual females are semelparous.<ref>Atlas of Crustacean Larvae</ref>

Classification

Five families are recognised:<ref name="WoRMS-Tantulocarida">Template:BioRef</ref> Template:Col-begin Template:Col-break Basipodellidae Boxshall & Lincoln, 1983:<ref>Template:Cite web</ref>

Doryphallophoridae Huys, 1991:<ref>Template:Cite web</ref>

Microdajidae Boxshall & Lincoln, 1987:<ref>Template:Cite web</ref>

Template:Col-break Cumoniscidae Nierstrasz & Brender à Brandis, 1923 (formerly family Deoterthridae:<ref name="WoRMS-Cumoniscidae">Template:BioRef</ref>

Onceroxenidae Huys, 1991:<ref>Template:Cite WoRMS</ref>

Template:Col-end

References

Template:Reflist

Template:Arthropods Template:Taxonbar

Retrieved from "https://wiki.sarg.dev/index.php?title=Tantulocarida&oldid=234094"