Abraliopsis is a marine genus of squid (family Enoploteuthidae) of the phylum Mollusca. 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, and the formation and position of chromatophores. 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, 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 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 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