Ommastrephidae is a family of squid containing three subfamilies, 11 genera, and over 20 species. They are widely distributed globally and are extensively fished for food. One species, Todarodes pacificus, comprises around half of the world's cephalopodcatch annually. Some members of Ommastrephidae are known to have the ability to glide out of water, earning them the common name of "flying squid".
Description
The ommastrephids are small to large squids, with mantle lengths ranging from that of the glass squid at, to the Humboldt squid at. The mantle narrows towards the back and possesses large terminal fins. The family is characterized by an inverted T-shaped funnel locking cartilage. They have an easily recognizable, slender, feather-shaped gladius with a hollow cone structure. Light organs are present along the head and mantle of members of the subfamily Ommastrephinae. Ommastrephid arms have a double series of suckers. The enlarged tips of the tentacles have four rows of suckers, except in the genus Illex'', which has eight. Hooks are absent. One of the ventral arms develops into a secondarysexual organ in males. All ommastrephids are active predators. Their arms and tentacles bear sharp teeth and are used to grasp and bring prey to their beaked mouths. They are very strong swimmers, and some species are known to glide out of water to escape predators. Ommastrephid paralarvae are distinctive for having fused tentacles, looking like a single "proboscis". It gradually splits into two as the paralarvae grow becoming completely separated once they reach mantle lengths of.
Distribution and habitat
Ommastrephids usually occur in pelagic waters, but can also be found in neritic habitats. They are found worldwide.
Taxonomy
Ommastrephidae was first established by the DanishzoologistJapetus Steenstrup in 1857. It is classified under the suborderOegopsina of the orderTeuthida. It is divided into three subfamilies - Illicinae, Ommastrephinae, and Todarodinae; further subdivided into 11 genera and more than 20 species. These subfamilies, genera, species, and subspecies are classified under Ommastrephidae:
