Four new species of Polycirrus Grube, 1850 (Polychaeta: Terebellidae) from Campos Basin, southeastern Brazil.

Four new species of Polycirrus were collected at the Campos Basin, state of Rio de Janeiro, during a survey coordinated by CENPES/PETROBRAS under the scope of the project, "Environmental Heterogeneity in the Campos Basin". These species are P. nonatoi sp. nov., P. papillosus sp. nov., P. breviuncinatus sp. nov., and P. habitats sp. nov. All these species are herein described and compared with the morphologically most similar congeners. In addition, a key is provided for the identification of the species of Polycirrus which have been originally described for the Brazilian coast.