Taxonomic revision of Melanocyphus Jekel (Coleoptera: Curculionidae)

Melanocyphus Jekel is a broad-nosed weevil genus (Entiminae: Naupactini) endemic to the high Andes of Colombia, that includes two species, M. bispinus (Boheman) and M. lugubris (Boheman), mainly differentiated by the presence or absence of humeral teeth. Based on characters of the cuticle, vestiture, morphology of the antennae, rostrum and genitalia, Melanocyphus appears most closely related to Amitrus Schoenherr, a genus distributed in similar habitats and at similar elevations in Bolivia and Peru. Since the type species had not been designated, we proposed Cyphus bispinus (original combination) as type of Melanocyphus. This contribution includes redescriptions of the genus and its species, a dichotomous key, habitus photographs and illustrations of the diagnostic characters of the external morphology and genitalia.