Carnivorous sponges from deep-sea coral mounds in the Campos Basin (SW Atlantic), with the description of six new species (Cladorhizidae, Poecilosclerida, Demospongiae)

摘要

Species of Cladorhizidae are most frequently found associated with hard substrates in the deep sea, close to hydrothermal vents or cold water reefs. Deep sea coral mounds were recently found to occur at Campos Basin, and the ongoing study of these ecosystems has shown that they harbour a diverse sponge fauna. Further results along these lines are reported here, with a (re)description of Asbestopluma (A.) cf. calyx, and six new species from 605 to 1141 m depth: Abyssocladia sp. nov., Asbestopluma (A.) sp. nov. 1-4 and Cladorhiza sp. nov. The fact that all Cladorhizidae come from a relatively small sector of the SE South American slope suggests the diversity of these sponges may still be considerably larger in this area than known so far. The known diversity of cladorhizids in the SW Atlantic ranks intermediate between the richest areas of the NW Pacific (27 species) and the NE Atlantic (23 species), and the poorest ones such as the Mediterranean, the Southeast Atlantic and the whole of the Indian Ocean (1-6 species). Campos Basin yields over 1.5×10~6 barrels of oil/day, thus generating much concern on the preservation of these ecosystems.