Bathyteuthis abyssicola

Mantle & Fins

• Skin bright to dark red
• Fins small, widely separated,  each approximately circular in outline

Arms & Tentacles

• Arms short, stubby; arm tips blunt, not attenuate.
• Protective membranes low, fleshy, without free trabeculae
• Arm suckers relatively few in number, about 100 on each of arms I-III.
• Arm sucker rings with 8-18 separated, bluntly rounded to truncate protuberances
• Tentacles and clubs relatively short.

Bathyteuthis abyssicola, oral view of arm crown (from Roper, 1968).

Bathyteuthis abyssicola, arm sucker rings (from Roper, 1968).

Bathyteuthis abyssicola tentacle club (from Roper, 1968).

Internal anatomy

• Gills short, narrow
• Internal photophores absent

The type locality for B. abyssicola is in the southern Indian Ocean between the subantarctic islands of Crozet Is. and Prince Edward Is.

Vertical Distribution

This bathypelagic species normally occurs at 700-2000 m, but records are given as 100-4200 m. The greater depths are probably artifacts from open (non-closing) sampling nets. Paralarvae and juveniles live at shallower depths than adults. In the Southern Ocean (Antarctic Ocean), B. abyssicola undertakes a deep diel vertical migration (Roper, 1969). The population in the eastern tropical-subtropical North Atlantic also demonstrates a diel vertical migration (Clarke & Lu, 1975; Lu & Clarke, 1975).

Geographical Distribution

Bathyteuthis abyssicola is found throughout the world oceans. It is circumpolar in the Southern Ocean and in the highly productive waters of the eastern Pacific, the Atlantic, and the Indian Oceans (Roper, 1969).

Brooding has been reported in another bathyteuthid species, B. berryi (Bush et al., 2012; see video here), and probably also occurs in B. abyssicola. The female carries a sheet of several hundred eggs, presumably until they hatch and the paralarvae swim free. 

Paralarvae of 4 mm ML have very small, paddle-like, subterminal fins; strongly protruding, anteriorly directed eyes; extremely short, stubby arms with 6 minute suckers paired in 2 longitudinal series on arms I-III and 5 suckers in a zigzag row on arms IV. Tentacles are relatively long and clubs are undifferentiated with 18 minute suckers paired in 2 longitudinal series at the distal end. Immediately proximal to the suckers are 16 knob-like bumps paired in 2 longitudinal series that are precursors to suckers. By 6 mm ML the fins are much better developed, the very small photophores are developing on the aboral bases of arms I-III, and the tentacular suckers are in 5-6 longitudinal series along the club (Roper, 1969).

Bathyteuthis abyssicola was described in 1885 by Hoyle. Benthoteuthis megalops was described by Verrill, also in 1885. These species were recognized as being the same entity, but both names continued to be used for years because no firm date of priority for publication had been established. In 1900, Pfeffer finally synonymized Benthoteuthis megalops with Bathyteuthis abyssicola at the same time he erected the Family Bathyteuthidae. The actual dates of publication of these two species were not verified until 1969 when it was established conclusively that B. abyssicola had priority by two months (Roper, 1969).