Hyloxalus breviquartus is a species of frog in the family Dendrobatidae. It is found in the northern part of Cordillera Occidental in Antioquia, Colombia, and in Carchi Province in northwestern Ecuador. Colombian distribution may be wider. Its natural habitats are montane forests next to streams and very humid premontane forests. It is threatened by habitat loss, although it occurs in the Las Orquídeas National Natural Park, its type locality. Description Females measure in snout–vent length. References breviquartus Amphibians of the Andes Amphibians of Colombia Amphibians of Ecuador Taxa named by Marco Antonio Serna Díaz Taxa named by Juan A. Rivero Amphibians described in 1986 Taxonomy articles created by Polbot Fauna of the northwestern Andean montane forests