Oegopsida is one of the two orders of squid in the superorder Decapodiformes, in the class Cephalopoda. Together with the Myopsina, it was formerly considered to be a suborder of the order Teuthida, in which case it was known as Oegopsina. This reclassification is due to Oegopsina and Myopsina not being demonstrated to form a clade.
Oegopsida
A squid is a mollusc with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fitting these criteria. Like all other cephalopods, squid have a distinct head, bilateral symmetry, and a mantle. They are mainly soft-bodied, like octopuses, but have a small internal skeleton in the form of a rod-like gladius or pen, made of chitin.
Squid
Fossil Rhomboteuthis from the Lower Callovian (c. 164 Mya, middle Jurassic) of La Voulte-sur-Rhône, France
Fossil Plesioteuthis from the Tithonian (c. 150 Mya, upper Jurassic), Solnhofen, Germany
Basic squid features (ventral aspect)