This species is endemic to Colombia, where it is currently known from localities on both sides of the upper Río Atrato and arguably at three localities on the lower Río San Juan (Grant and Myers 2013). It occurs in the Serranía del Baudó, in the area surrounding the Alto del Buey, a geographic isolated area that can only be reached by sea or air. It occurs between 60–700 m asl. Its EOO is 15,925 km2 and it is considered to occur more widely (M. Anganoy-Criollo pers. comm. March 2017).
Habitat and Ecology
It has been found during the day in lowland forest and under forest floor leaf litter (Grant and Myers 2013). It is expected that the eggs are laid in the leaf litter, and tadpoles are transported to water to by the parents where they continue to develop, as with other congeners.
There is little information on the population size and trends of this species.
Threats to this species are not currently well understood because of the remoteness of the area. Alto del Buey is still largely forested, however the forest within the distribution of the species is declining due to small-scale wood extraction, and also there is mining activity for gold that pollutes the bodies of water (M. Anganoy-Criollo pers. comm. 2017).
The species has not been found in any protected area, although Parque Nacional Utría is located near the known distribution of the species (M. Anganoy-Criollo pers. comm. 2017).
The establishment of protected areas in the region is recommended since there are still large areas of forest remaining within the known distribution of the species.
In the past, the distribution of the species was under the control of different illegal armed groups, and now that the armed conflict has ceased it is recommended to collect more information about this species' distribution, population status, ecology, and threats.
Red List Status
Near Threatened (NT)
Listed as Near Threatened because its distribution is somewhat limited—extent of occurrence (EOO) is approximately 15,925 km2—and there is ongoing decline in habitat extent and quality due to small-scale logging and pollution from mining in part of its range. The species occurs in a remote area, which is unlikely to be severely threatened at present. The species therefore comes close to qualifying for Vulnerable B1, a criterion that may be applicable in the future if there is a change in land use.
IUCN SSC Amphibian Specialist Group 2017. Silverstoneia minutissima. The IUCN Red List of Threatened Species 2017: e.T78586339A85861216. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T78586339A85861216.en .Downloaded on 16 February 2019