This species is known only from the type locality: Huamba, 22 km ESE (airline) of Ayabaca, in the northern portion of the Cordillera de Huancabamba, Piura region, in northwestern Peru (Venegas et al. 2008). It occurs at an elevation of 2,950 m asl, its estimated extent of occurrence (EOO) is 10 km2, and all individuals are considered to occur in a single threat-defined location.
Habitat and Ecology
This species inhabits the cloud forest around Cerro Mayordomo. Individuals have been observed in leaf litter and along small streams (Venegas et al. 2008). Although there is limited ecological information, it is expected to breed in fast flowing streams by larval development, as with other congeners.
This species was observed in September 1987 and again in October 1997 (Venegas et al. 2008). However, surveys at the type locality and adjacent areas in May and September 2006 were unable to locate this species (Venegas et al. 2008). The largest nearby forest patch near the type locality, known as Bosque de Cuyas, was surveyed in 2001 without finding a trace of any harlequin frog. There is a possibility that this species may be extinct (P. Venegas pers. comm. October 2010), however if a population still exists it is thought to have less than 50 individuals. Due to ongoing decline in the extent and quality of habitat, the population is suspected to be decreasing.
The cloud forest surrounding Ayabaca and the type locality is severely threatened by habitat destruction due to an increase in cattle grazing and agricultural land use. The forest on the western slope of Cerro Mayordomo is fragmented with patches of less than 100 ha. The largest patch of montane forest near Cerro Mayordomo is found in the neighbouring locality of Anchalá. This isolated forest is known as Bosque de Cuyas and is completely surrounded by croplands (Venegas et al. 2008). Chytridiomycosis is likely to be a threat, which perhaps led to a prior catastrophic population decline, as has occurred in many other montane species of Atelopus. In addition, due to their limited geographical range, this species is expected to show limited climatic adaptability (Lötters 2007).
This species has not been recorded in any protected areas. No conservation measures are currently in place for this species and its immediate habitat. It is listed as Critically Endangered (CR) in Peru and has legal protection provided by the Categorization in Endangered Species of Wild Fauna (Decreto Supremo Nº004-2014-MINAGRI), which bans all hunting, capture, possession, transport or export of the species for commercial purposes.
Conservation of remaining forest fragments in the northern portion of the Cordillera de Huancabamba is a high priority. Ex situ measures are suggested to be absolutely necessary, if the species is still extant.
It is a very high priority to conduct surveys to locate this species and determine its current population status.
Red List Status
Critically Endangered (CR)
Listed as Critically Endangered (Possibly Extinct) as it is known only from the type locality and has not been recorded since 1997 despite surveys in 2001 and 2006. Its extent of occurrence (EOO) is estimated at 10 km2, it is only known from a single location, and there is a continuing decline in its cloud forest habitat in northern Peru due to encroaching agriculture, livestock farming and human habitation. If a population still exists, it is suspected to be less than 50 mature individuals.
IUCN SSC Amphibian Specialist Group 2018. Atelopus eusebiodiazi. The IUCN Red List of Threatened Species 2018: e.T158466A89221443. http://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T158466A89221443.en .Downloaded on 11 December 2018