This species is known from isolated localities on the Cordilleras Central and Occidental in Colombia. It was previously only known from Cerro Munchique and Quintana (near Popayán) in Cauca Department; but it is now also known from El Cerrito in Valle del Cauca Department, Salento in Quindío Department and one site in Caldas Department (M. Anganoy-Criollo unpubl. data 2016). The species may occur more widely in this region as appropriate habitat remains. It occurs between 2,100–2,350 m asl. It occurs in five threat-defined locations and its EOO is 13,037 km2.
Habitat and Ecology
This species occurs on the ground next to streams in cloud forests. It has not been recorded outside forest habitat. It lays its eggs on the ground which, when hatched, are transported on the backs of the male to temporary ponds where they develop further.
This species is rarely encountered. Three individuals were recorded in 2015 in Quintana (Cauca department) (J. Guerrero-Vargas, unpubl. data). Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.
The major threats are deforestation for agricultural development, the planting of illegal crops, logging, eucalyptus plantations, and human settlements.
This species occurs in Munchique National Park.
Additional protected areas in the Cordillera Central, which is suffering high rates of deforestation, are needed.
Additional survey efforts are needed to better understand the distribution and population trends.
Red List Status
Listed as Vulnerable because its extent of occurrence (EOO) is 13,037 km2, it occurs in fewer than 10 threat-defined locations, and there is ongoing decline in the extent and quality of habitat.
IUCN SSC Amphibian Specialist Group 2017. Colostethus mertensi. The IUCN Red List of Threatened Species 2017: e.T55115A85894530. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T55115A85894530.en .Downloaded on 20 January 2019