A new species of Eunicidae, Eunice decolorhami sp. n., from the southeastern Pacific Ocean, is described. The species was collected at the slope of the Desventuradas Islands (San Félix and San Ambrosio) and in three nearby seamounts of the Nazca Ridge, in dead coral rubble bottoms from 180 to 340 m depth and inhabiting inside parchment-like branched tubes. Eunice decolorhami sp. n. can be distinguished from other species of the genus, mainly by the coloration pattern of the subacicular hooded hooks along the body segments, the beginning of the subacicular hooded hooks, the beginning of the branchiae, the maximum number of branchial filaments, and the maxillary formula. A key for the seven Eunice species recorded off the coast of Chile and Peru, including the new species described herein, is provided.
Keywords: Polychaeta, Polychaeta, Eunicidae.