A new gorgonian genus from deep-sea Antarctic waters (Octocorallia, Alcyonacea, Plexauridae)

Abstract

Mesogligorgia scotiae gen. nov., sp. nov. is described and illustrated from a colony collected in the Scotia Sea, 2,201–2,213 m in depth, on the ANDEEP-I cruise. The new taxon is placed in the family Plexauridae because of: 1) the presence of a horny axis with a crosschambered central core and numerous loculi, 2) retractile polyps in calyces with distinct spicular components, and 3) armed polyps with large sclerites with a poorlydeveloped collaret and eight well-developed points. The irregularly distributed sclerites running along the axis, into a thick mesogloeal coenenchyme, and the elongated spindles with irregular ends are the most distinctive characters of the newly proposed genus.