Ecological and genetical survey on two deep-sea holothurians: Benthogone rosea and Benthodytes typical

Abstract

Ecological, biological and genetical features of 2 populations of deep-sea holothurlans have been studied. The 2 species concerned, Benthogone rosea Koehler and Benthodytes typica Theel belong to the strictly abyssal order Elasipoda. In the 2 collect~on areas they represent the dominant species of the megafauna. Trophic resources and other environmental characteristics are quite similar at the 2 sampling sites. Trawl captures and bottom photographic surveys suggest the presence of large populations. Results of genetic studies provide the first published estimates of very low levels of genetic polymorphism in populations of strictly abyssal species.