Hadropus Schoenherr, 1826 is a monotypic genus of Naupactini (Curculionidae: Entiminae), ranging in Brazil and Paraguay. It is easily recognized by the nebulose pattern of the elytral vestiture, the presence of very short rostrum and humped elytra with strongly bisinuate anterior margin. The morphological characters of the rostrum, antennae, legs, elytra and female genitalia relate Hadropus to Ericydeus Pascoe. Hadropus albiceris (Germar) shows variation in body size, morphometries of the pronotum and color of the scaly vestiture, that allows distinguishing two basic morphotypes. This paper includes descriptions of the genus and its single species, habitus photographs, line drawings of genitalia, and a map of distribution.