Bathyteuthis is the singular genus of squid in the family Bathyteuthidae, encompassing three species. None has a mantle length greater than 80 mm.
The family Cranchiidae comprises the approximately 60 species of glass squid, also known as cockatoo squid, cranchiid, cranch squid, or bathyscaphoid squid. Cranchiid squid occur in surface and midwater depths of open oceans around the world. They range in mantle length from 10 cm (3.9 in) to over 3 m (9.8 ft), in the case of the colossal squid. The common name, glass squid, derives from the transparent nature of most species. Cranchiid squid spend much of their lives in partially sunlit shallow waters, where their transparency provides camouflage. They are characterised by a swollen body and short arms, which bear two rows of suckers or hooks. The third arm pair is often enlarged. Many species are bioluminescent organisms and possess light organs on the undersides of their eyes, used to cancel their shadows. Eye morphology varies widely, ranging from large and circular to telescopic and stalked. A large, fluid-filled chamber containing ammonia solution is used to aid buoyancy. This buoyancy system is unique to the family and is the source of their common name "bathyscaphoid squid", after their resemblance to a bathyscaphe. Often the only organ that is visible through the transparent tissues is a cigar-shaped digestive gland, which is the cephalopod equivalent of a mammalian liver. This is usually held in a vertical position to reduce its silhouette and a light organ is sometimes present on the lower tip to further minimise its appearance in the water.
The Gonatidae, also known as armhook squid, are a family of moderately sized squid. The family contains about 19 species in three genera, widely distributed and plentiful in cold boreal waters of the Pacific Ocean. At least one species is known from Antarctic waters, and two from the North Atlantic. The genus Eogonatus was created for the species known as Eogonatus tinro because it did not have hooks on the tentacular club and it has 5 rows of teeth on the radula. Molecular studies in allozymes and mitochondrial DNA have indicated that this species nests within the genus Gonatus, although other authorities treat it as a synonym of Gonatopsis okutanii.
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.
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 cephalopod catch annually.
Grimpoteuthis is a genus of pelagic umbrella octopuses known as the dumbo octopuses. The name "dumbo" originates from their resemblance to the title character of Disney's 1941 film Dumbo, having a prominent ear-like fin which extends from the mantle above each eye. There are 13 species recognized in the genus. Prey include crustaceans, bivalves, worms and copepods. The average life span of various Grimpoteuthis species is 3 to 5 years.
The Ariidae or ariid catfish are a family of catfish that mainly live in marine waters with many freshwater and brackish water species. They are found worldwide in tropical to warm temperate zones. The family includes about 143 species.
Incirrata is a suborder of the order Octopoda. The suborder contains the classic "benthic octopuses," as well as many pelagic octopus families, including the paper nautiluses. The incirrate octopuses are distinguished from the cirrate octopuses by the absence in the former of the "cirri" filaments for which the cirrates are named, as well as by the lack of paired swimming fins on the head, and lack of a small internal shell.
Galiteuthis is a genus of glass squids from the family Cranchiidae and the subfamily Taoniinae. Squids in the genus Galiteuthis are large squids with mantle lengths measuring up to 660mm, although it has been suggested that mantle length could reach as much as 2.7m. The most distinctive feature of the speciesa in this genus are they have hooks on the tentacular clubs while there are no hooks on the arms, and by their long, thin, terminal fins.
Thaumeledone is a genus of octopuses in the family Octopodidae found in deep waters in the Southern Hemisphere.
The Littorinidae are a taxonomic family of over 200 species of sea snails, marine gastropod molluscs in the clade Littorinimorpha, commonly known as periwinkles and found worldwide.
Bathyteuthis abyssicola, also known as the deepsea squid, is a species of squid in the family Bathyteuthidae.
Lepidoperca is a small genus of fish belonging to the Anthiadinae subfamily. It includes ten species.
Loliolus is a genus of squid from the family Loliginidae from the Indo-Pacific region. The genus is divided into two subgenera Loliolus and Nipponololigo. They are small squids of less than 150mm in mantle length which have an expanded tentacular club. This club has 4 series of suckers. The sucker ringss have plate-like teeth which are square in shape all around them. The males' hectocotylus has a ventral crest which is created by the fusion of the protective membrane with the ventral series of papillae and this crest completely obscures the conical shape of the papillae. The mantle is rounded posteriorly and lacks the posterior tail-like lobe while the fins are positioned on the rear of the mantle and extend to the posterior tip of the mantle. Their eggs are small and the males' spermatophore has a short cement body. They do not possess photophores. The two subgenera are distinguished by the hectocotylus which in Loliolus encompasses the enire arm and there are no unmodified suckers while in Nipponololigo the arm is only partly hectocotylsed and has normal suckers at its base.
Lolliguncula is a genus of squid from the family Loliginidae from the eastern Pacific and western Atlantic, known as brief squid. The genus is divided into two subgenera Lolliguncula and Loliolopsis. They are rather small squids with a maximum mantle length of 120mm, that inhabit shallow warm seas, although some species have been recorded in areas of low salinity. They are typified by having a short mantle, which is round at the posterior; and fins that are broader than long, but which have no posterior lobes. The males produce spermatophores with a long cement body and they lack a ventral crest on their hectocotylus. Their suckers have square teeth which ring the entire margin or are placed distally. The males do not have enlarged suckers on the left ventral arm. The tentacular club is expanded and contains suckers in four series. The two subgenera differ in the morphology of the hectocotylus.
Sepia cultrata, commonly known as the knifebone cuttlefish or elongated cuttlefish, is a species of cuttlefish from the family Sepiidae endemic to the southern Indo-Pacific. It is a deepwater species found in subtropical and temperate Australian waters.
