''Abraliopsis'' is a marine genus of

squid A squid (: squid) is a mollusc with an elongated soft body, large eyes, eight cephalopod limb, arms, and two tentacles in the orders Myopsida, Oegopsida, and Bathyteuthida (though many other molluscs within the broader Neocoleoidea are also ...

(family Enoploteuthidae) of the phylum

Mollusca Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

. Not much is known about ''Abraliopsis'' due to the evading ability of pelagic cephalopods. Features that distinguish these species include the absence of arm suckers, size and number of hooks on arms, the presence of

photophores A photophore is a specialized anatomical structure found in a variety of organisms that emits light through the process of Bioluminescence, boluminescence. This light may be produced endogenously by the organism itself (symbiotic) or generat ...

, and the formation and position of

chromatophores Chromatophores are cells that produce color, of which many types are Biological pigment, pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals an ...

. 11 species that make up the Enoploteuthidae family.

Species

The following species are listed as members of the genus ''Abraliopsis'': *Subgenus ''Abraliopsis'' Joubin, 1896 **'' Abraliopsis hoylei'' (Pfeffer, 1884) **'' Abraliopsis morisii'' ( Vérany, 1839), Pfeffer's enope squid **'' Abraliopsis pacificus '' Tsuchiya & Okutani, 1990 **'' Abraliopsis tui'' Riddell, 1985 *Subgenus ''Boreabraliopsis'' Tsuchiya & Okutani, 1988 **'' Abraliopsis felis'' McGowan & Okutani, 1968 *Subgenus ''Micrabralia'' Pfeffer, 1900 **'' Abraliopsis gilchristi'' Robson, 1924 **'' Abraliopsis lineata'' Goodrich, 1896 *Subgenus ''Pfefferiteuthis'' Tsuchiya & Okutani, 1988 **'' Abraliopsis affinis'' (Pfeffer, 1912) **'' Abraliopsis atlantica'' Nesis, 1982 **'' Abraliopsis chuni '' Nesis, 1982 **'' Abraliopsis falco ''

Young Young may refer to: * Offspring, the product of reproduction of a new organism produced by one or more parents * Youth, the time of life when one's age is low, often meaning the time between childhood and adulthood Music * The Young, an America ...

, 1972

Geographic Distribution

''Abraliopsis'' species usually exist in tropical and subtropical habitats, with a high presence in the coastal regions of California and Mexico, including the Gulf of Mexico. Other species of ''Abraliopsis'' are present down the eastern Pacific coast streaming into the regions of Chile, Ecuador and Columbia. ''Abraliopsis'' species also are present in coastal Indian/African regions but are poorly studied,

Feeding and Ecological Importance

Similar to other small marine organisms, ''Abraliopsis'' follow the

diel vertical migration Diel vertical migration (DVM), also known as diurnal vertical migration, is a pattern of movement used by some organisms, such as copepods, living in the ocean and in lakes. The adjective "diel" ( IPA: , ) comes from , and refers to a 24-hour ...

feeding pattern to feed near the surface at night. This is a common strategy for vulnerable organisms to avoid predators while feeding. Pelagic marine organisms and seabirds prey on ''Abraliopsis''. ''Abraliopsis'' was found in the stomach contents of a variety of common marine fish and seabirds. ''Abraliopsis'' are also members of the micronekton community near seamounts. Juveniles and paralarvae of some cephalopods may be related to primary production in

upwelling Upwelling is an physical oceanography, oceanographic phenomenon that involves wind-driven motion of dense, cooler, and usually nutrient-rich water from deep water towards the ocean surface. It replaces the warmer and usually nutrient-depleted sur ...

areas, which are nutrient dense areas that support the marine ecosystem.

Morphology

''Abraliopsis'' are characterized by the presence of photophores on the ventral surface of the head and protective membranes on left arm IV. ''Abraliopsis pfefferi'' undergo constant bodily growth with a clear size difference between male and female individuals. Size variation occurs within each sex. Maturation age differ amongst the males and females, with 120-130 days for males and 150-160 days for females. Males have a shorter overall maturation time than females. Mantle length grows at a relatively slow speed of 0.5–0.6% every day.

References

External links

Tree of Life web project: ''Abraliopsis''
Enoploteuthidae Cephalopod genera Bioluminescent molluscs {{squid-stub