''Stauroteuthis'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of deepwater

octopus An octopus ( : octopuses or octopodes, see below for variants) is a soft-bodied, eight- limbed mollusc of the order Octopoda (, ). The order consists of some 300 species and is grouped within the class Cephalopoda with squids, cuttle ...

, a

cephalopod A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...

mollusk Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...

. This is the only genus in the family Stauroteuthidae, and only two species have been described in this genus. The organisms live below water depth; although sometimes found as deep as underwater, they generally live at a water depth of around . They do not possess a

radula The radula (, ; plural radulae or radulas) is an anatomical structure used by molluscs for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food ...

. The stauroteuthids have the distinction of being one of the few

bioluminescent 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 Fungus, fungi, microorganisms including ...

octopuses; some of the muscle cells that control the suckers in most species have been replaced with

photophore A photophore is a glandular organ that appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors, ...

s which are believed to fool prey by directing them towards the mouth.

Species

* '' Stauroteuthis gilchristi'' is only known from two localities in the south Atlantic; these two localities may even represent different species. * '' Stauroteuthis syrtensis'' is widespread in the

North Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the "Old World" of Africa, Europe and ...

. The

population Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction using a ...

size of ''S. syrtensis'' is unknown.''Stauroteuthis syrtensis'' Verrill, 1879
Encyclopedia of Life.

References

External links

Tree of Life website gives information about the classification of cephalopod groupsStauroteuthidae discussion forum at TONMO.com
Octopuses Taxa named by Addison Emery Verrill {{octopus-stub