The Chiroteuthidae are a family of deep-sea squid, generally small to medium in size, rather soft and gelatinous, and slow moving. They are found in most temperate and tropical oceans, but are known primarily from the North Atlantic, North Pacific, and Indo-Pacific. The family is represented by approximately 12 species and four subspecies in four genera, two of which are monotypic. They are sometimes known collectively as whip-lash squid, but this common name is also applied to the Mastigoteuthidae, which are sometimes treated as a subfamily (Mastigoteuthinae) of Chiroteuthidae.
The Mastigoteuthidae, also known as whip-lash squid, are a family of small deep-sea squid. Approximately 20 known species in six genera are represented, with members found in both the mesopelagic and bathypelagic zone of most oceans. Originally described by Verill in 1881, it was later lowered by Chun (1920) to a subfamily (Mastigoteuthinae) of the Chiroteuthidae. However, Roper et al. (1969) raised it back to the family level, and this has not been changed since. The taxonomy of this family is extremely unstable, and there have been at times one genus, two genera and four subgenera(Salcedo-Vargas & Okutani, 1994), two genera and several 'groups', five genera and one species with an uncertain placement, or six genera.
Helicocranchia pfefferi, the banded piglet squid, is a small squid of the genus Helicocranchia. Adults of this species are mesopelagic.
Idioteuthis cordiformis is a species of whip-lash squid found in tropical regions of the west Pacific Ocean. The species is commonly known as the 'love-heart squid' because the species name cordiformis is Latin for 'heart shaped'. Recently, this species has been found to consume small birdbeak dogfish.
Echinoteuthis danae is a species of whip-lash squid. Known only from specimens of paralarvae, the species may be the juvenile form of Echinoteuthis atlantica.
Mastigoteuthis is a genus of whip-lash squid containing at least seven valid species. Some teuthologists consider Idioteuthis synonymous with this taxon.
Echinoteuthis is a genus of whip-lash squid containing approximately three to five species. Some teuthologists consider Idioteuthis synonymous with this taxon.
Magnoteuthis is a genus of whip-lash squid containing at least three species. Some teuthologists consider Idioteuthis or Mastigoteuthis synonymous with this taxon, but it is genetically and morphologically distinct.
Mastigopsis is a genus of whip-lash squid containing one single species, Mastigopsis hjorti. Some teuthologists consider Idioteuthis synonymous with this taxon; however, genetic results indicate that this genus is not closely related with Idioteuthis but actually closer to Magnoteuthis.
Mastigoteuthis agassizii is a species of whip-lash squid. It is the type species of the genus.
Echinoteuthis atlantica is a species of whip-lash squid from the family Mastigoteuthidae. It occurs in the eastern North and South Atlantic Ocean. This squid is red in colour and similar to Echinoteuthis famelica of the Pacific but differs in having a well developed protective membrane on the tentacular club which is absent on E. famelica. The presence on this membrane on Echinoteuthis glaukopis from the Indian Ocean suggests that this may be a synonym of E. atlantica, in which case glaukopis has priority.
Mastigoteuthis dentata is a species of whip-lash squid.
Mastigoteuthis magna is a species of whip-lash squid, characterised by a lack of photophores. The skin is heavily pigmented a deep red by a numerous chromatophores.
Mastigoteuthis psychrophila is a species of whip-lash squid. It was first described by Kir Nazimovich Nesis in 1977, based on four individuals found in Antarctic waters. The largest was 143 mm long. The squid's tentacles are 15 mm in diameter, with 0.15 mm diameter club suckers. Integumental photophores are present upon the head, arms and fins. Although uncertain, it is believed to have more than two series of photophores on the arms, differing from other species in the M. agassizii group. However, this species, like the rest of the family, is badly in need of revision.
Mastigoteuthis pyrodes is a species of whip-lash squid.
Pterygioteuthis giardi is a species of squid in the family Pyroteuthidae. It is known as the roundear enope squid. The specific name honors the French zoologist and marine biologist Alfred Mathieu Giard (1846-1908).
Pyroteuthis addolux is a species of squid in the family Pyroteuthidae. It is distinguished from other members of the genus Pyroteuthis by the shape of photophores on the tentacles and the shape of the hectocotylus. The hectocotylus is located on arm IV, containing 10 proximity hooks, and six to 15 suckers at the tip. P. addolux ranges from south of the Hawaiian Islands, to the subantarctic boundary. They exhibit minor geographical variance, as southern specimens are slightly smaller than their northern counterparts. P. addolux is the only member of the genus to occur in the North Pacific, but additional members of the family Pyroteuthidae have also been found. The species has been observed using bioluminescence to reduce its silhouette in dim surrounding light. The type specimen was taken off southern California and described in 1972 by Richard E. Young.
Argyropelecus affinis is a species of ray-finned fish in the family Sternoptychidae, described by Garman in 1899, found in the tropical and subtropical Atlantic, Indian and Pacific Oceans. Common names for this fish include Pacific hatchetfish, deepsea hatchetfish and slender hatchetfish. It inhabits the upper mesopelagic zone between 350 and 600m during the day, and between 100m and 350m during the night and is either non-migratory or performs short daily vertical migrations. They are distributed widely throughout all tropical and temperate seas. They are known for its laterally compressed body and characteristic photophores, which aid in bioluminescence. Argyropelecus affinis is closely related to Argyropelecus gigas.
Lampadioteuthis megaleia is a small, colorful squid, the only species in the only genus in the monotypic family Lampadioteuthidae. It is sometimes known as the wonderful firefly squid. It was formerly classified in the family Lycoteuthidae, but differs from them mainly by having a hectocotylus in the males and by the possession of a rostrum on the gladius.
Eucleoteuthis is a monotypic genus of squid from the family Ommastrephidae; the only species is Eucleoteuthis luminosa, the striped flying squid or luminous flying squid.
