A new species of Leposphilus Hesse, 1866 (Copepoda: Philichthyidae) parasitic in the interorbital canals of the whitemouth croaker Micropogonias furnieri (Desmarest) (Sciaenidae) off Brazil with an amended diagnosis of the genus.

A new species of the monotypic genus Leposphilus Hesse, 1866 (Cyclopoida: Philichthyidae), Leposphilus vogti n. sp., is described based on adult female and male specimens from the interorbital canals of Micropogonias furnieri (Desmarest) (Sciaenidae) in Sepetiba Bay, State of Rio de Janeiro, Brazil. The new species differs from its only congener, L. labrei Hesse, 1866, by the following combination of characters in the adult female: a globular cephalosome, a two-segmented maxilla, and fourth abdominal somite fused to caudal ramus; and in the adult male: presence of maxilliped, leg 3 with five setae, and caudal rami tipped with six setae. In addition, an amendment of diagnosis of Leposphilus is provided based on the characters of the new species. Previous records of philichthyid copepods from actinopterygians in the Atlantic and Pacific Oceans off the American continent are also given.