Histioteuthis

Histioteuthis is a genus of squid in the family Histioteuthidae. It goes by the common name cock-eyed squid, because in all species the right eye is normal-sized, round, blue and sunken; whereas the left eye is at least twice the diameter of the right eye, tubular, yellow-green, faces upward, and bulges out of the head.

Histioteuthis
A member of the genus Histioteuthis. Eye asymmetry is observable.
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Order:	Oegopsida
Family:	Histioteuthidae
Genus:	Histioteuthis Orbigny, 1841[1]
Type species
Cranchia bonnellii Férussac, 1834
Species
17 species and subspecies, see text
Synonyms[1]
Calliteuthis Verrill, 1880 Histiopsis Hoyle, 1885 Histiothauma Robson, 1948 Hoylia Cossmann, 1900 Lolidona Risso, 1854 Meleagroteuthis Pfeffer, 1900

Beak of Histioteuthis bonnellii

In 2017, researchers at Duke University established that Histioteuthis uses its larger eye to see ambient sunlight, and its smaller eye to detect bioluminescence from prey animals.^[2]

The name is composed of the Greek histion (ἱστίον, "sail", a large webbed membrane between six of the arms, in some species) and teuthis ("squid").^[3][4]

The genus contains bioluminescent species.^[5]

Species

• H. bonnellii species-group
  • Histioteuthis bonnellii, umbrella squid
  • Histioteuthis machrohista
• H. reversa species-group
  • Histioteuthis eltaninae
  • Histioteuthis atlantica
  • Histioteuthis reversa, reverse jewel squid
• H. celetaria species-group
  • Histioteuthis celetaria
  • Histioteuthis pacifica
• H. corona species-group
  • Histioteuthis berryi
  • Histioteuthis cerasina
  • Histioteuthis corona
  • Histioteuthis inermis
• H. miranda species-group
  • Histioteuthis miranda
  • Histioteuthis oceani
• H. meleagroteuthis species-group
  • Histioteuthis heteropsis, strawberry squid
  • Histioteuthis meleagroteuthis