A new deep-sea genus of Nannastacidae (Crustacea, Cumacea) from the Lucky Strike hydrothermal vent field (Azores Triple Junction, Mid-Atlantic Ridge)

Abstract

A new cumacean genus and species, Thalycrocuma sarradini gen. et sp. nov., belonging to the family Nannastacidae is described from several sites of the Lucky Strike hydrothermal vent field (Mid-Atlantic Ridge, 37°N, 1700 m depth). The new genus differs from others in the family by males lacking exopods on the pereopods 3 and 4 and having an antenna with a five-articulate peduncle and a short flagellum. This is the first cumacean species that could be considered, at the moment, as endemic from hydrothermal vent areas. Data on the accompanying fauna including other cumacean species (Cyclaspis longicaudata, Bathycuma brevirostre, Procampylaspis sp. and Makrokylindrus sp.) and some ecological remarks are included. A key for the currently known genera of the family Nannastacidae is provided and the taxonomic position of some genera is discussed.

Keywords:

• Cumacea
• deep sea
• hydrothermal vents
• Mid-Atlantic Ridge
• morphology
• systematics

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark

Acknowledgements

We thank the chief scientists Pierre-Marie Sarradin (ATOS, Ifremer), Daniel Desbruyères (PICO, Ifremer), Ana Colaço (Arquipélago, IMAR, Portugal), Mikhail Ivanov (TTR10 and TTR12, Moscow State University, Russia) and José Hipólito Monteiro (TTR10 and TTR12, INETI, Portugal); Alexis Khripounoff (Ifremer), responsible for the sediment trap; as well as the captains and crew of the R/Vs L'Atalante, Nadir, Arquipélago and Prof. Logatchev, and the pilots of the submersibles Nautile and ROV Victor 6000. This work was partly funded through the MAST 3, AMORES (MAS3-CT95-0040) and VENTOX European projects (EVK3-1999-00003). R. Fontarnau and collaborators are also thanked for their assistance during SEM sessions in the Serveis Cientificotècnics (University of Barcelona).

Notes

Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark