Squid Squid Squid are cephalopods in the order Teuthida with elongated bodies, large eyes, eight arms and two tentacles. 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 can change colour for camouflage and signalling. Some species are bioluminescent, using their light for counter-illumination camouflage. Squid are members of the class Cephalopoda, subclass Coleoidea. The squid orders Myopsida and Oegopsida are in the superorder Decapodiformes (from the Greek for "ten-legged"). Two
Cephalopod limb infundibulum and acetabulum causes attachment and detachment. Many octopus arm anomalies have been recorded, including a 6-armed octopus (nicknamed Henry the Hexapus), a 7-armed octopus, a 10-armed "Octopus briareus", one with a forked arm tip, octopuses with double or bilateral hectocotylization, and specimens with up to 96 arm branches. Branched arms and other limb abnormalities have also been recorded in cuttlefish, squid, and bobtail squid. Cephalopod limbs and the suckers they bear are shaped in many distinctive ways, and vary considerably between species. Some examples are shown below. For hectocotylized arms see hectocotylus variability. Cephalopod limb All cephalopods possess flexible