Observations from submersibles of rare long-arm bathypelagic squids

Two rare and unique cephalopods were observed and filmed at 2950-3010 m depth off the coasts of Ghana and Ivory Coast in July 1992, a third at 4735 m north of Brazil in September 1988 and a fourth specimen northwest of Mauritius in the Indian Ocean in May 2000 at 2576 m. The first of these specimens was filmed 20 cm above a sedimentary seafloor. The second observation was filmed in midwater 40 min later and during the same dive. The cephalopods belonged to an unknown species. The most remarkable features are the extremely long filaments at the tip of each arm and tentacle, and their extraordinarily wide rhomboid fins, occupying about two-thirds of the mantle length. The morphology and behaviour of these unknown cephalopods are described from video records obtained from the manned submersible Nautile . Possible systematic placement of these specimens is discussed.

Keywords:

• Bathypelagic
• Cephalopods
• Long-ARM Squid
• Submersible