Oegopsina

Oegopsina is a suborder of the squid order, Teuthida, in the Cephalopoda class. Some taxonomists raise it to the level of an order, in which case it is known as Oegopsida. This is due to Oegopsina and Myopsina not being demonstrated to form a clade.

The Oegopsina are an often pelagic squid, with some nerito-oceanic species associated with sea mounts. (from http://www.fao.org/docrep/014/i1920e/i1920e04.pdf) They consist of 24 families and 69 genera. They have these characters in common: the head is without tentacle pockets, eyes lack a corneal covering, arms and tentacle clubs may have hooks, the buccal supports are without suckers, and oviducts in females are paired.

Two families, the Bathyteuthidae and Chtenopterygidae, which have features characteristic of the Myopsina while retaining others common to the Oegopsina, are sometimes placed in the Bathyteuthoidea.

The Oegopsina differ from the coastal Myopsina, characterised by the genus Loligo, which have corneal coverings over the eyes and tentacle pockets, but lack hooks, have no suckers on the buccal supports, and a single oviduct.

Oegopsid squid are the only decapods that lack a pocket for the tentacles. Otherwise, they share different characters with different decapod groups. Like the Bathyteuthoidea and Myopsina, the Oegopsina have a brachial canal, which is absent in other forms. As with the Spirulidae and Idiosepiidae, the Oegposina lack suckers on the buccal supports, and like the Bathyteuthoidea, Idiosepiidae, and Spirulidae, they have no circular muscle on the suckers.