Revision of the genus Orcus Mulsant (Coleoptera: Coccinellidae: Chilocorini)

Species of the genus Orcus Mulsant, 1850 are revised, keyed and illustrated. Orus biroi var. ruficollis Weise, 1902 is regarded as a synonym of Orem biroi Weise, 1902 new synonym. Lectotypes are designated for Orcus biroi Weise, Orcus biroi var. ruficollis Weise, Orem cinctm Weise and Orem nigricollis Weise. Three new species, all from New Guinea, are described: Orem cordifomiis, O. tetrafasciatus, O. viridulus. Orem carinicm Gorham, O. bipunctatm Gorham and O. quadriguttatm Gorham are removed from Chilocorini and transferred to the genus Sticholotis Crotch (Sticholotidini) (new combinations). Distribution, nomenclatural history and diagnoses are provided for each species.