Gnamptogenys triangularis is a Neotropical species of ants in the subfamily Ectatomminae. Native to the forests of South and Central America, G. triangularis is a predatory ant that feeds on millipedes. In its native range, this species is known from Buenos Aires, Argentina in the south to Costa Rica in the north, with records from eight countries in South America, and two countries of Central America. The first records of G.