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 Park, its type locality.
Females measure 15–17 mm (0.59–0.67 in) in snout–vent length.
