Brachioteuthis riisei is a species of squid in the family Brachioteuthidae.[2]

Brachioteuthis riisei
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Oegopsida
Family: Brachioteuthidae
Genus: Brachioteuthis
Species:
B. riisei
Binomial name
Brachioteuthis riisei
Synonyms[2]

Entomopsis alicei Joubin, 1900
Entomopsis velaini Rochebrune, 1884
Tracheloteuthis riisei Steenstrup, 1882
Verrilliola nympha Pfeffer, 1884

Description edit

This is a small species. It is almost colourless except for small chromatophores scarcely distributed. It has a long, thin, cylindrical mantle which grows to from 10 to 17 cm in length. The fin is approximately 35–50% of the length of the mantle. It has weak muscles, yet is nektonic.[3]

Larval stage edit

The neck of the larva is long. Their arms have two rows of suckers, with the having multiple rows of smaller suckers in the tentacular club at the proximal hub.[3]

Distribution edit

This species is widely distributed and is native to many parts of the Atlantic and Pacific Oceans, and the Mediterranean and Black Seas.[1] Except within the boreal Pacific Ocean, this is likely a cosmopolitan species.[3]

Habitat and biology edit

Young animals live in the epi-mesopelagic zone, with adults occurring in the bathypelagic zone.[3] Brachioteuthis riisei is an oceanic species which can be found over a wide range of depths from the surface to 3,000 m depth. Juvenile animals occur throughout the year which suggests that this species has an extended spawning season, although the juveniles reach peak abundance between May and August and in February in the North Atlantic while the peaks in the Mediterranean and off Northwest Africa are from April to July, in September, and from December to February. Brachioteuthis riisei is preyed upon by a range of marine mammals including Cuvier's beaked whale (Ziphius cavirostris)[1] and striped dolphin (Stenella coeruleoalba),[4] as well as by fish, for example the blue shark (Prionace glauca)[1] and, in the Azores, the swordfish (Xiphias gladius), as well as by the giant red shrimp (Aristaeomorpha foliacea) in the Sicilian Channel.[4]

References edit

  1. ^ a b c d Allcock, L.; Barratt, I. (2014). "Brachioteuthis riisei". IUCN Red List of Threatened Species. 2014: e.T163095A972086. doi:10.2305/IUCN.UK.2014-1.RLTS.T163095A972086.en. Retrieved 11 November 2021.
  2. ^ a b c Bieler R, Bouchet P, Gofas S, Marshall B, Rosenberg G, La Perna R, Neubauer TA, Sartori AF, Schneider S, Vos C, ter Poorten JJ, Taylor J, Dijkstra H, Finn J, Bank R, Neubert E, Moretzsohn F, Faber M, Houart R, Picton B, Garcia-Alvarez O, eds. (2024). "Brachioteuthis riisei (Steenstrup, 1882)". MolluscaBase. World Register of Marine Species. Retrieved 25 March 2024.
  3. ^ a b c d "Marine Species Identification Portal : Brachioteuthis riisei". species-identification.org.
  4. ^ a b P. Jereb; C.F.E. Roper, eds. (2010). Cephalopods of the World an Annotated and Illustrated Catalogue of Cephalopod Species Known to Date Volume 2 Myopsid and Oegopsid Squids (PDF). Food and Agriculture Organization Rome. pp. 131–132. ISBN 978-92-5-106720-8.