Natural feeding of the temperate asymbiotic octocoral-gorgonian Leptogorgia sarmentosa (Cnidaria: Octocorallia)

Este artículo contiene10 páginas, 1 tabla, 2 figuras.Octocorals are common components of sublittoral benthic communities in temperate, tropical and polar areas. However, their natural diets and feeding rates are poorly known. In this study, we examined natural feeding and respiration of the ubiquitous temperate species Leptogorgia sarmentosa (Cnidaria: Octocorallia) in the NW Mediterranean. We measured in situ grazing rate on dissolved organic carbon (DOC), detrital particulate organic carbon (POC) and live particulate carbon <100 µm (i.e. pico- and nanoplankton, dinoflagellates, diatoms and ciliates) using continuous flow incubation chambers. L. sarmentosa captured nanoeukaryotes, dinoflagellates, diatoms, ciliates, as well as detrital POC, but no significant capture of DOC, nor of prey items smaller than nanoeukaryotes (mean 3.6 µm), was observed. Feeding rate on detrital POC and live carbon <100 µm was 402 ± 35 and 67 ± 6 µg C g ash-free dry mass (AFDM)-1 h-1, respectively. Detrital POC and zooplankton‹previously studied‹were the 2 main food sources, while live carbon