Three new species are described from Piauí, in Cerambycinae: Compsibidion pictum, sp. nov. (Neoibidionini); in Lamiinae: Adetus differentis sp. nov. (Apomecynini) and Mimasyngenes piauiensis sp. nov. (Desmiphorini). From 75 species proceeding from Riacho dos Bois (Parque Nacional da Serra das Confusões), 50 are new records from Piauí. Three subfamilies are recognized: one species of Prioninae, 46 species of Cerambycinae and 28 species of Lamiinae.
Apomecynini; Desmiphorini; Neoibidionini; Neotropical