Abundance of the bearded fireworm Hermodice carunculata (Polychaeta: Amphinomidae) increases across a euphotic-mesophotic depth gradient in the remote St. Peter and St. Paul’s Archipelago

The bearded fireworm Hermodice carunculata is widely distributed across tropical and subtropical Atlantic Mediterranean Oceans was previously considered to be mostly associated with shallow reefs. We provide here data on the distribution, abundance habitat use of H. a euphotic-mesophotic gradient (0-90 m) in Saint Peter Paul’s Archipelago (SPSPA, Mid Ridge, Brazil). Samples were obtained using SCUBA Remote Operated Vehicle (ROV). A total 189 individuals observed sharp increase depth recorded, particularly from 50 m onwards. In mesophotic zone (50-90 closely branching black-corals (Tanacetipathes spp.) predation over scleractinian Madracis decactis commonly sighted. Boosted Regression Tree model indicated black-coral as main driver abundance, suggesting that preference for optimal habitats hide/forage more important than per se bathymetric distribution fireworm. high abundances zone, its keystone benthic cnidarians, suggests this species play roles dynamics deep