Light squid

Light squid
	Glowing Squid ( Watasenia scintillans )
Systematics
Trunk :	Molluscs (mollusca)
Class :	Cephalopods (cephalopoda)
Order :	Squids (Teuthida)
Family :	Enoploteuthidae
Genre :	Watasenia
Type :	Light squid
Scientific name of the genus
	Watasenia
	Ishikawa , 1914
Scientific name of the species
	Watasenia scintillans
	( Berry , 1911)

The light squid ( Watasenia scintillans ) is an octopus (Coleoidea) and belongs to the class of cephalopods (Cephalopoda).

description

The light squid is a small species of squid that only grows to around three to four inches. As usual for squids, it has ten arms, two of which are elongated and serve as tentacles . Eight arms are covered with stalked suction cups. The tentacles are free from suction cups and have 2 to 3 hooks in a row. At the rear end of the body, two side fins are used for rapid movement. The animals have pigment-containing cells, chromatophores , and light-emitting cells of photophores that are distributed over the body and that luminesce (photophores, however, not on the dorsal side ). The species can distinguish colors with its highly developed lens eyes.

nutrition

The light squid attracts small fish with its photophores, which it then embraces in its arms.

distribution

The species occurs only on the shelf and the shallower waters around Japan and in the China Sea to the north of the Sea of Okhotsk . The animals normally live at a depth of 200 to 400 m, but come to mating and laying eggs in shallower waters and in the Toyama Bay of the Sea of Japan also relatively close to the coasts.

development

The eggs are mainly laid in the upper 80 m in the open water between February and July. In some areas, eggs are laid almost all year round. A female can lay up to 20,000 eggs in strands up to 1 m in length. The single egg measures about 1.5 × 1 mm. The young hatch from the eggs after 6 to 14 days, depending on the water temperature (the warmer the water, the faster the young hatch). The hatchling measures around 1.2 to 1.4 mm. The average life expectancy of the animals is only about 1 year.

Enemies

Glowing squids are hunted by large bottom fish and relatives of salmon .

Importance to fishing

The light squid is fished commercially in waters around Japan. Between 1990 and 1999, between 5,000 and 7,000 tonnes were caught each year. The animals are fished between March and June.

Taxonomy

The species is the only species in the genus Watasenia (Ishikawa, 1914).

literature

Richard E. Young, LA Burgess, CFE Roper, MJ Sweeney and SJ Stephen: Classification of the Enoploteuthidae, Pyroteuthidae and Ancistrocheiridae. Smithsonian Contributions to Zoology 586: 239-255, Washington, DC 1998.
Kir N. Nesis & Lourdes A. Burgess (ed.): Cephalopods of the world: squids, cuttlefishes, octopuses, and allies . 351 pp., Neptune City, NJ 1987.