AbstractThe genus Ericydeus Pascoe (Polydrosinae: Naupactini) distributed throughout the United States of America up to Argentina is revised and a cladistic analysis including 16 species is conducted. Three new species are described: E. bahiensis, E. argentinensis and E. cupreolus. Ericydeus humeralis Hustache is synonymized under E. nigropunctatus (Chevrolat); and E. modestus viridans (Boheman) and E. modestus duodecimpunctatus (Dalla-Torre, Emden & Emden) are elevated to species rank. Other valid species are: E. hancocki (Kirby), E. schoenherri (Perty), E. sedecimpunctatus (Linnaeus), E. yucatanus (Champion), E. roseiventris (Champion), E. quadripunctatus (Champion), E. modestus (Gyllenhal), E. forreri (Champion), E. lautus (LeConte) and E. placidus (Horn). In the cladogram obtained the species from South America gather in a clade (E. argentinensis, E. sedecimpunctatus, E. nigropunctatus, E. schoenherri, E. hancocki, and E. bahiensis) and the species from Central and North America form a separate clade (E. yucatanus, E. roseiventris - E. quadripunctatus, E. cupreolus, E. viridans - E. modestus, E. duodecimpunctatus, E. forreri, E. lautus - E. placidus). The character evolution follows a southern-northern direction. The paper includes a redescription of the genus, redescriptions or descriptions of its 16 species, a dichotomous key, habitus photographs, drawings of diagnostic structures, distribution maps, a cladogram, and a discussion of the phylogeny and distribution of the genus.