# Myopsida > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Myopsida > Markdown URL: https://mediated.wiki/source/Myopsida.md > Source: https://en.wikipedia.org/wiki/Myopsida > Source revision: 1354729350 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Order of squids}} {{Automatic taxobox | fossil_range = {{fossil range|Cenomanian|recent|earliest=Callovian|[Cenomanian](/source/Cenomanian) - recent,{{Cite journal|last1=Ikegami |first1=Shin |last2=Takeda |first2=Yusuke |last3=Mutterlose |first3=Jörg |last4=Iba |first4=Yasuhiro |title=Origin and radiation of squids revealed by digital fossil-mining |year=2025 |journal=Science |volume=388 |issue=6754 |pages=1406–1409 |doi=10.1126/science.adu6248 |pmid=40570114 }} possible Jurassic records?{{cite journal |last1=Fischer |first1=Jean-Claude |last2=Riou |first2=Bernard |title=Les teuthoïdes (Cephalopoda, Dibranchiata) du callovien inférieur de la Voulte-sur-Rhône (Ardèche, France) |journal=Annales de Paléontologie |date=1982 |volume=68 |issue=4 |pages=295-325 |url=http://jurassic.ru/pdf/Fischer_&_Riou_1982.pdf}}}} | image = Squid eye.jpg | image_caption = Eye of myopsid squid showing corneal membrane and lack of secondary eyelid | taxon = Myopsida | authority = [d'Orbigny](/source/Alcide_d'Orbigny), 1841{{cite web | url = http://www.marinespecies.org/aphia.php?p=taxdetails&id=11728 | title = Myopsida | accessdate = 22 February 2018 | publisher = Flanders Marine Institute | author = Philippe Bouchet | year = 2018 | website = World Register of Marine Species}} | subdivision_ranks = Families | subdivision = [Australiteuthidae](/source/Australiteuthidae)
[Loliginidae](/source/Loliginidae) }} '''Myopsida''' is one of the four [orders](/source/Order_(biology)) of [squid](/source/squid). It consists of two [families](/source/Family_(taxonomy)): the [monotypic](/source/monotypic) ''[Australiteuthis](/source/Australiteuthis)'' and the diverse and commercially important [Loliginidae](/source/Loliginidae) (~50 species). Some [taxonomist](/source/taxonomist)s classify this taxon as a suborder of the order [Teuthida](/source/Teuthida), in which case it is known as Myopsina. This reclassification is due to Myopsina and [Oegopsina](/source/Oegopsina) not being demonstrated to form a [clade](/source/clade).{{cite book | editor1 = S. Blair Hedges | editor2 = Sudhir Kumar | year = 2009 | title = The Timetree of Life | chapter = Cephalopod mollusks Cephalopoda | pages = 2–18 | publisher = OUP Oxford | author1 = Jan M. Strugnell | author2 = Annie Lindgren | author3 = Louise M. Allcock | author3-link = Louise Allcock }} A number of morphological features distinguish members of Myopsida from those of its sister group, [Oegopsida](/source/Oegopsida). Some of the most obvious differences are found in the structure of the [eyes](/source/cephalopod_eye): those of myopsid squids lack a [secondary eyelid](/source/secondary_eyelid) and are instead covered by a transparent [corneal membrane](/source/cephalopod_cornea), the opening of which is reduced to a microscopic [anterior pore](/source/eye_pore) in most species. The [arms and tentacles](/source/cephalopod_limb) are ornamented with simple [suckers](/source/cephalopod_sucker) (hooks are never present), with additional suckers usually borne on the [buccal lappet](/source/buccal_lappet)s. The carpal ("wrist") portion of the [tentacular club](/source/tentacular_club) lacks a [locking apparatus](/source/carpal-locking_apparatus), and a [tentacle pocket](/source/tentacle_pocket) is present on the head. The [funnel](/source/siphon_(mollusc)) has no lateral [adductor muscles](/source/Adductor_muscle_(Bivalvia)). An internalised shell is present in the form of a well-developed [gladius](/source/Gladius_(cephalopod)), which is located dorsally within the [mantle](/source/mantle_(mollusc)) and extends for almost its entire length. In contrast to oegopsids, females possess [accessory nidamental gland](/source/accessory_nidamental_gland)s in addition to the main [nidamental gland](/source/nidamental_gland)s. They however lack a right [oviduct](/source/oviduct).Jereb, P. & C.F.E. Roper (2010). Squids. In: P. Jereb & C.F.E. Roper (eds.) ''[http://www.fao.org/docrep/014/i1920e/i1920e00.htm Cephalopods of the world. An annotated and illustrated catalogue of species known to date. Volume 2. Myopsid and Oegopsid Squids]''. FAO Species Catalogue for Fishery Purposes No. 4, Vol. 2. FAO, Rome. pp. 34–35.Vecchione, M. & R.E. Young (2008). [http://www.tolweb.org/Myopsida/52670 Myopsida Naef, 1916]. [Tree of Life Web Project](/source/Tree_of_Life_Web_Project). Myopsids are found in [coastal waters](/source/neritic_zone) worldwide. They are [demersal](/source/demersal_zone), generally feeding on or near the bottom. In turn, they are considered prey items by virtually all marine predators, including birds. Adult sizes range from the dwarf ''[Australiteuthis](/source/Australiteuthis)'' and ''[Pickfordiateuthis](/source/Pickfordiateuthis)'', whose males mature at less than {{convert|2|cm|in|abbr=on}} in mantle length (ML), to the largest species ''[Loligo forbesii](/source/Loligo_forbesii)'', which has been measured to {{convert|93.7|cm|ft|abbr=on}} ML.[https://www.cambridge.org/core/journals/marine-biodiversity-records/article/abs/azorean-loligo-forbesi-cephalopoda-loliginidae-in-captivity-transport-handling-maintenance-tagging-and-survival/B348C459B4EDFB2A530EA33DA4C88CB4 The Azorean Loligo forbesi (Cephalopoda: Loliginidae) in captivity: transport, handling, maintenance, tagging and survival][https://assets.researchsquare.com/files/rs-1926159/v1/a1b1c776-782d-4066-9c21-4b5cbb6aa7a6.pdf?c=1694444921 Body size and fin length as determinants in the geographic distribution of Loliginid squids] Until 2025, the earliest fossils of this group were ''[Loligo](/source/Loligo)'' [statoliths](/source/Statocyst) from the early [Eocene](/source/Eocene) of [North America](/source/North_America). In 2025, numerous well-preserved fossil beaks, identifiable to several new genera in the [Loliginidae](/source/Loliginidae), were described from the [Late Cretaceous](/source/Late_Cretaceous) of Japan, dating back to the earliest [Cenomanian](/source/Cenomanian). In addition, a pyritized ''Loligo'' fossil is known from the [Oligocene](/source/Oligocene) of [Russia](/source/Russia), marking the earliest true squid known from a complete body fossil.{{Cite journal |last=Mironenko |first=Aleksandr A. |last2=Boiko |first2=Maxim S. |last3=Bannikov |first3=Alexandre F. |last4=Arkhipkin |first4=Alexander I. |last5=Bizikov |first5=Viacheslav A. |last6=Košťák |first6=Martin |date=10 August 2021 |title=First discovery of the soft‐body imprint of an Oligocene fossil squid indicates its piscivorous diet |url=https://www.idunn.no/doi/10.1111/let.12440 |journal=Lethaia |language=en |volume=54 |issue=5 |pages=793–805 |doi=10.1111/let.12440 |issn=0024-1164|url-access=subscription }} ==References== {{Reflist}} {{Taxonbar|from1=Q18816667|from2=Q1062108}} Category:Myopsida Category:Decapodiformes Category:Squid {{squid-stub}} --- Adapted from the Wikipedia article [Myopsida](https://en.wikipedia.org/wiki/Myopsida) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Myopsida?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.