{{Short description|Infraorder of crustaceans}} {{multiple image | width=220 | align = right | direction = vertical | image1 = Upogebia deltaura.jpg | caption1 = ''Upogebia deltaura'' (Gebiidea: Upogebiidae) | image2 = Pestarella tyrrhena.jpg | caption2 = ''Pestarella tyrrhena'' (Axiidea: Callianassidae) }} '''Thalassinidea''' is the former infraorder classification of decapod crustaceans that live in burrows in muddy bottoms of the world's oceans. In Australian English, the littoral thalassinidean ''Trypaea australiensis'' is referred to as the ''yabby''<ref>{{cite book |chapter-url=http://dictionary.oed.com/cgi/entry/50288585?query_type=word&queryword=yabby&first=1&max_to_show=10&sort_type=alpha&result_place=1&search_id=56QR-RvFgUX-9957&hilite=50288585 |chapter=Yabby |title=Oxford English Dictionary |publisher=Oxford University Press}}</ref> (a term which also refers to freshwater crayfish of the genus ''Cherax''), frequently used as bait for estuarine fishing; elsewhere, however, they are poorly known, and as such have few vernacular names, "mud lobster" and "ghost shrimp" counting among them. The burrows made by thalassinideans are frequently preserved, and the fossil record of thalassinideans reaches back to the late Jurassic.<ref>{{cite journal |author=Nguyen Ngoc-Ho |year=1981 |title=A taxonomic study of the larvae of four thalassinid species (Decapoda, Thalassinidea) from the Gulf of Mexico |journal=Bulletin of the British Museum (Natural History), Zoology |volume=40 |issue=5 |pages=237–273 |url=http://decapoda.nhm.org/pdfs/20428/20428.pdf |format=PDF}}</ref>
The group was abandoned when it became clear that it represented two separate lineages, now both recognised as infraorders: Gebiidea and Axiidea.<ref name="Sakai">{{cite journal |author=K. Sakai |year=2004 |journal=Crustaceana |title=The diphyletic nature of the Infraorder Thalassinidea (Decapoda, Pleocyemata) as derived from the morphology of the gastric mill |volume=77 |issue=9 |pages=1117–1129 |doi=10.1163/1568540042900268 |jstor=20107419}}</ref><ref name="Grave">{{cite journal |journal=Raffles Bulletin of Zoology |year=2009 |volume=Suppl. 21 |pages=1–109 |title=A classification of living and fossil genera of decapod crustaceans |author1=Sammy De Grave |author2=N. Dean Pentcheff |author3=Shane T. Ahyong |url=http://rmbr.nus.edu.sg/rbz/biblio/s21/s21rbz1-109.pdf |format=PDF |display-authors=etal |archive-date=2019-01-07 |access-date=2010-01-15 |archive-url=https://web.archive.org/web/20190107045823/http://rmbr.nus.edu.sg/rbz/biblio/s21/s21rbz1-109.pdf%20 |url-status=dead }}</ref> Recent molecular analyses have shown that thalassinideans are most closely related to Brachyura (crabs) and Anomura (hermit crabs and their allies). There are believed to be 556 extant species of thalassinideans in 96 genera,<ref>{{cite journal |author=Peter C. Dworschak |year=2005 |journal=Nauplius |url=http://www.nhm-wien.ac.at/Content.Node/forschung/3zoo/Dworschak2005b_homepage.pdf |volume=13 |issue=1 |pages=57–63 |title=Global diversity in the Thalassinidea (Decapoda): an update (1998-2004) |format=PDF}}{{dead link|date=October 2024}}</ref> with the greatest diversity in the tropics, although with some species reaching latitudes above 60° north. About 95% of species live in shallow water, with only three taxa living below {{convert|2000|m}}.<ref>{{cite journal|author=Peter C Dworschak |year=2000 |title=Global diversity in the Thalassinidea (Decapoda) |journal=Journal of Crustacean Biology |volume=20 |issue=5 |pages=238–243 |url=http://decapoda.nhm.org/pdfs/12157/12157.pdf |format=PDF|jstor=1549501 | doi = 10.1163/1937240X-90000025|doi-access=free }}</ref>
==See also== {{Portal|Crustaceans}} *''Thalassinoides''
==References== {{Reflist|32em}}
==External links== *{{Wikispecies-inline|Axiidea}} *{{Wikispecies-inline|Gebiidea}}
Category:Thalassinidea Category:Obsolete arthropod taxa