What is the biggest species of squid?
30627361#1
Ommastrephinae includes the largest species of squids belonging to the family Ommastrephidae, Humboldt squid ("Dosidicus gigas") which can grow to in mantle length (ML). It also contains the smallest squid species belonging to the family, the glass squid ("Hyaloteuthis pelagica") which has a mantle length of only up to . Ommastrephinae are mostly pelagic members of the family Ommastrephidae. All species of this subfamily contain photophores whose locations vary by species. Some species of the subfamily (notably "Sthenoteuthis" and "Ommastrephes") are known for their behavior of leaping out of the water (hence the common names 'flying squid').
Ommastrephinae
20975773#0
The colossal squid ("Mesonychoteuthis hamiltoni", from Greek "mesos" (middle), "onycho" (claw, nail), and "teuthis" (squid)), sometimes called the Antarctic squid or giant cranch squid, is believed to be the largest squid species in terms of mass. It is the only known member of the genus "Mesonychoteuthis". It is known from only a few specimens, and current estimates put its maximum size at long and weighing possibly up to , based on analysis of smaller and immature specimens, making it the largest-known invertebrate.
Colossal squid
7099622#0
Megalocranchia fisheri is a species of glass squid. Its natural range covers at least the waters off Hawaii. The species may attain a mantle length of and a total length of over , making it one of the largest species of squid, together with the colossal squid ("Mesonychoteuthis hamiltoni"), giant squid ("Architeuthis" sp.), and robust clubhook squid ("Onykia robusta"). It inhabits surface and mid-depth waters of open ocean. Juveniles live near the surface, while adults occupy mesopelagic depths during the day and migrate to near-surface waters at night. "M. fisheri" possesses two large light organs in the gill cavity. Females additionally have light organs on the ends of their third arm pair. As the animal matures, its fins become spear-like in appearance.
Megalocranchia fisheri
28055763#6
It is one of the planet’s most economically significant invertebrate species. As many as 2.2 billion pounds of Argentine shorfin squid have been captured in only one fishing season. From 1988-2003 about 700,000 tons of Argentine shortfin squid were captured . Argentine shortfin squid are so important as they make up the second largest fishery in the world by weight . Fisheries use bright lights to attract the squid to the surface at night, and then capturing them with large nets. Fisheries additionally use both trawlers and jigging vessels to capture the shortfin squid. Although so many Argentine shortfin squid are removed from the coasts every year, populations bounce back, probably because of their short lifespan 
. They are thus labeled a species of least concern. That being said however, since 2010 stocks have steadily been declining. It is suggested that environmental changes instead of fishery impacts have caused this decline. It is essential that the nations that house this species must cooperate in order to ensure that the species is used by fisheries in a sustainable manner.
Illex argentinus
38011#29
The majority of squid are no more than long, although the giant squid may reach . The smallest species are probably the benthic pygmy squids "Idiosepius", which grow to a mantle length of , and have short bodies and stubby arms.
Squid
7115086#0
Taningia danae, the Dana octopus squid, is a species of squid in the family Octopoteuthidae. It is one of the largest known squid species, reaching a mantle length of and total length of . The largest known specimen, a mature female, weighed .
Taningia danae
7100079#0
Cranchia scabra is a species of glass squid. It is the only species in the genus, and is fairly small (about 150 mm). The mantle is covered by large, multi-pointed cartilagenous tubercles. When disturbed, the squid often pulls its head and arms into the mantle cavity and folds its fins tightly against the mantle to form a turgid ball. The tubercules, presumably, provide some type of protection, but it is unclear what predators are affected and how. In addition, the squid may ink into the mantle cavity, making the ball opaque. This was thought to be an aberrant behavior due to stress and confinement of shipboard aquaria until the same inking behavior was seen in cranchiids from submersibles. The function of this behavior is unknown.
Cranchia scabra
38011#31
In 2003, a large specimen of an abundant but poorly understood species, "Mesonychoteuthis hamiltoni" (the colossal squid), was discovered. This species may grow to in length, making it the largest invertebrate. In February 2007, a New Zealand fishing vessel caught the largest squid ever documented, weighing and measuring around off the coast of Antarctica. Dissection showed that the eyes, used to detect prey in the deep Southern Ocean, exceeded the size of footballs; these may be among the largest eyes ever to exist in the animal kingdom.
Squid
20611428#81
Many aquatic molluscs are present in Antarctica. Bivalves such as "Adamussium colbecki" move around on the seafloor, while others such as "Laternula elliptica" live in burrows filtering the water above. There are around 70 cephalopod species in the Southern Ocean, the largest of which is the colossal squid ("Mesonychoteuthis hamiltoni"), which at up to is among the largest invertebrate in the world. Squid makes up most of the diet of some animals, such as grey-headed albatrosses and sperm whales, and the warty squid ("Moroteuthis ingens") is one of the subantarctic's most preyed upon species by vertebrates.
Southern Ocean
23644490#0
Gonatus is a genus of squid in the family Gonatidae, comprising twelve species, and therefore containing the most species in the family. Adult squid belonging to species in this genus are notable for their lack of tentacles.
Gonatus