A new species of oribatid mites from the Galapagos Islands, Ceratozetes yupanqui n. sp. is described and illustrated. It is morphologically most similar to two South American species, Ceratozetes platyrhinus and C. platyrhinoides, in having a broadened rostrum without incisions, but the new species exhibits consistent morphological differences in comparison to these species which are discussed. Numerous specimens of Ceratozetes yupanqui n. sp. were found on western islands of the archipelago, in moister habitats at higher altitudes in leaf and grass litter, as well as in arid lowlands in dry leaf and cactus litter. In previous listings of Galapagos species, Humerobates rostrolamellatus was erroneously reported as "Porozetes sp." Additional morphological features of this species are presented, based on the record from the Galapagos Islands. Morphological differences between H. rostrolamellatus and H. flechtmanni from Brazil are highlighted.