European squid propulsion. The posterior border is slightly concave. The head is relatively small and has large eyes which are covered with a transparent membrane. Like almost all squid, this species has ten limbs surrounding the mouth and beak: eight are relatively short arms, and two, which form the tentacles, are long, as they are used to catch prey. The fourth left arm of males is a hectocotylus. The European squid can grow up to 30–40 cm in the mantle length, but more usually they are 15–25 cm long. The males are generally bigger than the females and exhibit more rapid rates
Bathyteuthis abyssicola without free trabeculae (beam- or finger-like protuberances). Suckers are relatively few in number, about 100 on each of the upper six arms (pairs I–III). Sucker rings on the arms have 8–18 separated, bluntly rounded to truncate protuberances. The tentacles and clubs are relatively short. Gills are short and narrow. They have large photosensitive vesicles just behind the eyes which appear to detect bioluminescence. These photosensitive vesicles are among the largest known in any cephalopod. Bathyteuthis abyssicola Bathyteuthis abyssicola, also known as the deepsea squid, is a species of squid in the family Bathyteuthidae. "Bathyteuthis abyssicola" is the type species of