Omiodes Guenée is redescribed based on all New World species, including the type species O. humeralis Guenée. Four new species from Costa Rica, O. janzeni sp. n., O. hallwachsae sp. n., O. sirena sp. n., O. ochracea sp. n., are described. Ten new synonymies are established : Phostria disciiridescens Hampson is =O. croeceiceps (Walker), Phostria cayennalis Schaus is =O. grandis (Druce), Omiodes ochrosoma Felder & Rogenhofer and Phryganodes gazalis Schaus are =O. pandaralis (Walker), Nacoleia lenticurvalis Hampson, Phryganodes anchoritalis Dyar, and Phostria duplicata Kaye are =O. confusalis (Dognin), O. cervinalis Amsel is =O. martvralis (Lederer), Nacoleia indicata ab. pigralis Dognin and Botis fortificalis Möschler are =O. metricalis (Möschler). One new combination is recognized: O. pandaralis (Walker) was transferred from Coelorhynchidia Hampson. A key and an updated checklist to the neotropical Omiodes species is provided, including O. indicata (Fabricius), a worldwide pest. Ten species that do not belong in Omiodes are retained until appropriate generic placements are identified.