This species is known from six geographic localities within Sierra de Perijá, Venezuela (F. Rojas-Runjaic pers. comm. April 2011). Three of them are concentrated in the surroundings of Cerro Las Antenas, municipality of Rosario de Perijá, between 1,438 and 1,933 m asl, and the remaining three are within the Tokuko river basin, municipality of Machiques de Perijá, between 1,389 and 1,670 m asl, both in Zulia State (Barrio-Amorós et al. 2010). Its extent of occurrence (EOO) was calculated from a polygon area including all the localities where this species was found and it is estimated to be 2,284 km². Despite survey efforts throughout suitable neighbouring areas, this species has only been found in these six localities (arranged into two threat-defined locations), but is expected to occur more widely across Sierra de Perijá; specifically, from 1,400 to 1,950 m asl in between the 60 km between the furthermost known localities (F. Rojas-Runjaic pers. comm. March 2011).
Habitat and Ecology
This species occurs in premontane and montane forest, suitable areas for ombrophilous submontane evergreen forest vegetation (Barrio-Amorós et al. 2010). It was collected in rocky creeks surrounded by dense primary cloud forest, secondary and short forest between antennas at the summit of Cerro Las Antenas, and plantations and surroundings of the Yukpa village named Yurumuto and Pishikakao, both at the Tukuko River basin (Barrio-Amorós et al. 2010). Males have been found vocalizing actively in choruses on leaves of bushes and palms, and from forest leaf litter level up to four metres above the ground at night time at the end of the dry season (Barrio-Amorós et al. 2010). This species is presumed to breed by direct development. Since it has been found in secondary forest near antennas in Cerro las Antenas and in coffee plantations within the Tokuko river basin, it is presumed to tolerate a degree of habitat disturbance, although it is not thought to survive within malanga (eddoe) plantations given that these areas are being completely cleared (F. Rojas-Runjaic pers. comm. March 2011).
It is considered to be abundant in a third of the total number of localities, whereas it is rare in the rest of the localities where it was found (F. Rojas-Runjaic pers. comm. March 2011). Its population is not considered to be severely fragmented.
Within the altitudinal range occupied by this species in the Tokuko river basin, there is intense habitat fragmentation due to intrusive agricultural activities by Yukpa indigenous people and persistent deforestation activities by criollo inhabitants, who cultivate malanga using a highly destructive procedure (Barrio-Amorós et al. 2010). In Cerro Las Antenas, the areas where this species occurs are still pristine habitat patches, but in lower altitudes, between 400 and 1,400 m asl, there is infrastructure development for radio and TV antennas as well as moderate to strong intrusion into the forest by peasants that cultivate malanga; extensive cultivation of this and other crops have eliminated many hectares of the natural forest (Barrio-Amorós et al. 2010). Although this species occurs in unaltered habitat patches above 1,400 m asl, its current range is not protected, and could be potentially disturbed in the future and rapidly destroyed by extensive cultivation (Barrio-Amorós et al. 2010; F. Rojas-Runjaic pers. comm. March 2011). Also, in Cerro Las Antenas there is currently civil unrest (Barrio-Amorós et al. 2010). Overall, since there is intense habitat loss in the three localities lying along the Tokuko river basin, it is considered that agriculture is currently affecting 50% of the areas where this species occurs and the rate could be increasing in the future due to the possible expansion of agriculture towards higher elevations in Cerro Las Antenas (F. Rojas-Runjaic pers. comm. March 2011).
Cerro Las Antenas is unprotected but the southernmost localities of this species in the Tokuko river basin lie inside the Parque Nacional Sierra de Perijá (Barrio-Amorós et al. 2010). Improved protected area management and additional habitat protection are priorities for this species given the high rate of habitat loss experienced throughout its geographic range in the Tokuko river basin (including localities in Parque Nacional Sierra de Perijá) and most of its elevational range by small and large-scale agricultural activities in that area. Regulation of malanga cultivation is urgently needed within and surrounding Parque Nacional Sierra de Perijá (F. Rojas-Runjaic pers. comm. March 2011). Also, switching from malanga cultivation to less destructive and suitable crops would be strongly recommended (F. Rojas-Runjaic pers. comm. March 2011). Further survey efforts are needed to fully understand this species' distribution (F. Rojas-Runjaic pers. comm. March 2011).
Red List Status
Listed as Endangered because its extent of occurrence (EOO) is estimated to be 2,284 km², it is known from two threat-defined locations, and there is continuing decline in the extent and quality of the majority of its habitat in the Sierra de Perijá.
IUCN SSC Amphibian Specialist Group, 2012. Pristimantis rivasi. The IUCN Red List of Threatened Species 2012: e.T194803A2363093. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T194803A2363093.en .Downloaded on 15 December 2018