''Pyroteuthis addolux'' is a species of

squid True squid are molluscs with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fitting t ...

in the family Pyroteuthidae. It is distinguished from other members of the genus ''

Pyroteuthis ''Pyroteuthis'' is a genus of squid in the family Pyroteuthidae. It is differentiated from the genus '' Pterygioteuthis'' by size, head shape and behaviour. Species within the genus are separated by the arrangement of tentacular photophores; the ...

'' by the shape of photophores on the

tentacle In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...

s and the shape of the

hectocotylus A hectocotylus (plural: ''hectocotyli'') is one of the arms of male cephalopods that is specialized to store and transfer spermatophores to the female. Structurally, hectocotyli are muscular hydrostats. Depending on the species, the male may use i ...

. 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

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

an 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.Richard Brodeur and Orio Yamamura. 2005
MICRONEKTON OF THE NORTH PACIFIC
North Pacific Marine Science Organisation (PICES): pg21. The species has been observed using

bioluminescence Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some b ...

to reduce its silhouette in dim surrounding light. The

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

was taken off southern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

and described in 1972 by

Richard E. Young Richard E. Young (born August 20, 1938) is a teuthologist. He is an Emeritus Professor of Oceanography at the University of Hawaii's School of Ocean and Earth Science and Technology. Education Young took a Bachelor of Arts degree at Pomona College ...

. ''Pyroteuthis addolux'' apparentlyt undergoes a diel vertical migration in which spends th day at depths of 450-500 mbefore ascending to 150-200m at night to feed, most likely on copepods and other small crustaceans. The larger individuals do not appear to migrate each night. The

oocyte An oocyte (, ), oöcyte, or ovocyte is a female gametocyte or germ cell involved in reproduction. In other words, it is an immature ovum, or egg cell. An oocyte is produced in a female fetus in the ovary during female gametogenesis. The female ...

s contained in the ovary of a sexually mature female had a length of 1.0mm, when they hatch they produce

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

paralarva Paralarvae (singular: ''paralarva'') are young cephalopods in the planktonic stages between hatchling and subadult. This stage differs from the larval stage of animals that undergo true metamorphosis. Paralarvae have been observed only in membe ...

. The males have short

spermatophore A spermatophore or sperm ampulla is a capsule or mass containing spermatozoa created by males of various animal species, especially salamanders and arthropods, and transferred in entirety to the female's ovipore during reproduction. Spermatophores ...

References

Pyroteuthidae Molluscs described in 1972 {{squid-stub