Despite the numerous records of ant-mimicking arthropods, reports of ant species that are mimics among themselves are still rare. In the savannah of central Brazil we found two ant species that are remarkably similar in color pattern and body size, Pseudomyrmex termitarius and Camponotus blandus . Both species are widely distributed in the Neotropical Region, but the cases of mimicry between them are apparently restricted to populations inhabiting nests of the termite Cornitermes cumulans in the Brazilian Cerrado . Field observations and excavation of the termitaries revealed that Camponotus blandus shares nest chambers and foraging trials with P. termitarius, and workers of both species are mutually tolerant. Our observations suggest that the morphological and behavioral similarities between these species represent a Batesian mimicry relationship in which the relatively palatable Camponotus blandus mimics the unpalatable P. termitarius for predator avoidance. The pacific association between the termitophilous colonies of these species may also suggest some level of parabiotic interaction.