The cavernicolous swimming crab Atoportunus dolichopus Takeda, 2003 (Crustacea, Decapoda, Portunidae) reported for the first time in the Western Indian Ocean during technical dives in the mesophotic zone

Abstract

The rare cavernicolous crab Atoportunus dolichopus Takeda, 2003, described from Kume-Jima Island, Ryukyu archipelago, is recorded for the first time since its description. Two pecimens were observed in a marine cave off Mayotte Island, Western Indian Ocean, during technical dives in the mesophotic zone. The crabs were observed in total darkness at a depth of 75m, 120m from the entrance of the cave. No specimens were collected but morphological traits recognized on close-up photographs agree with those of A. dolichopus. This rare species is illustrated with comments on its remarkable disjunct geographical distribution and ecology.