ABSTRACTDifferent studies have indicated that there is a high prevalence of neoplasms in nonhuman primates; however, in Platyrrhini species, and especially in South American species, the available information is very scarce. The black howler monkey (Alouatta caraya) is the most widely distributed species in northeastern Argentina. In this contribution, we report an adult male individual of A. caraya with an important maxillofacial lesion whose morphological and radiographic characteristics allow us to diagnose it as the first record of a desmoplastic ameloblastoma in this species. The occurrence of this benign neoplasm raises the need to increase population monitoring, as well as the postmortem analysis of the different carcasses recovered from the different regions inhabited by this species.