Rhoptobaris LeConte (= Orthoris LeConte, new synonymy), a small genus of North and Central American weevils, is revised. The adult, larva, and pupa are described. Five species are recognized: Rhoptobaris canescens LeConte, Rhoptobaris cylindrifera (Casey), new combination [from Orthoris], Rhoptobaris obrieni Prena, new species [El Salvador, Honduras, Mexico], Rhoptobaris piercei Prena, new species [Mexico, USA], and Rhoptobaris scolopax (Say), new combination [from Aulobaris LeConte]. At least three species are associated with blazingstar (Mentzelia L., Loasaceae). Orthoris angustula Casey, Orthoris captiosa Casey, Orthoris crotchii LeConte, Orthoris robustula Casey, Orthoris tenuirostris Casey, and Orthoris tumidirostris Casey are new synonyms of R. scolopax. Lectotypes are designated for R. canescens, O. crotchii, O. captiosa, Orthoris cylindrifera Casey, and O. tenuirostris. Baridius anthracinus Boheman is designated as the type species for Aulobaris LeConte. Aulobaris pusilla (LeConte) is recognized as the valid name for B. scolopax of authors (not Say 1832). Habitus images of all five species, line drawings of important larval characters, and a key for the identification of the adult weevil are provided.