Carotenoid pigments and trophic behaviour of deep-sea shrimps (Crustacea, decapoda, alvinocarididae) from a hydrothermal area of the mid-atlantic ridge.

Pigments and trophic behaviour of three species of Alvinocarididae from a Mid-Atlantic hydrothermal site were analysed. Carotenoid pigments are responsible for the more or less marked colouration of these animals. The carotenoid content of whole animals and different tissues were evaluated. Rimicaris exoculata exhibits an increased carotenoid level at the juvenile stage, while Chorocaris chacei and Alvinocaris markensis contain only few traces of pigment. Free and esterified astaxanthin, reported for most pelagic crustaceans, are present in these deep-sea shrimps. The origin of carotenoids of crustaceans living in the aphotic zone is discussed.