The amphinomid polychaete Linopherus cf. canariensis was recorded for the first time in the coast of Rio de Janeiro (South-east Brazil). In 2011, a total of 15 specimens were collected in the intertidal zone of Itaipu Beach (Niterói) in dead Encope emarginata test fragments. In this study, the specimens are described, and a brief discussion about their morphological variation and invading potential is provided.