Clinging behaviour in a hadal scavenging amphipod (Amphipoda: Stegocephalidae)

Le résumé fourni par la source

Abstract Deep-sea amphipods frequently cling to elevated biogenic structures such as cnidarians and poriferans to provide elevation advantages and refuge. Clinging behaviour is rarely documented in amphipods from hadal depths (>6,000 m), likely reflecting sampling bias associated with the predominant use of baited traps which preferentially target taxa from scavenging guilds. We report the first documented observation of clinging behaviour by a hadal scavenging amphipod species from the family Stegocephalidae Dana, 1852. The specimens represent an undescribed species belonging to the genus Parandaniexis Schellenberg, 1929 and is here referred to as Parandaniexis sp. JAVA. This species was observed during baited lander deployments and a submersible dive at depths of 7,168–7,192 m in the Java Trench (East Indian Ocean). Parandaniexis sp. JAVA was observed in high numbers (>100 individuals) with many competing successfully for bait with the characteristic hadal lysianassid scavengers Bathycallisoma schellenbergi (Birstein & Vinogradov, 1958) and species of Eurythenes S.I. Smith in Scudder, 1882. Individuals of Parandaniexis sp. JAVA repeatedly adopted elevated, stationary positions on biotic and abiotic structures rather than partaking in the feeding aggregation. This prolonged station-holding behaviour distinguished Parandaniexis sp. JAVA from the sympatric hadal scavengers also observed throughout the deployments.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.