This species is found in the mountains of the Central Cordilleras, on northern Luzon and along its eastern and western coastal mountain ranges (Ilocos Norte, Kalinga, Apayao, Aurora, and Cagayan Provinces), in the Philippines (Brown et al. 2000, Diesmos et al. 2005, Siler et al. 2011, Brown et al. 2012, 2013). It ranges from ca 500 to more than 1,100 m asl.
Habitat and Ecology
This species inhabits arboreal microhabitats in mossy and montane rainforests, and can be found on low hanging tree branches, leaves, and shrubs (Siler et al. 2011). Heavily disturbed and regenerating forests support many subpopulations of this species (Brown et al. 2012). Males are frequently heard calling from the forest canopy and from understory vegetation immediately following rain and is most frequently encountered on axils and along fronds of aerial ferns (Brown et al. 2012, 2013). This species deposits direct-developing embryos in small clutches (6–8 eggs) on fern axils (Brown et al. 2012).
It is apparently common in appropriate forest habitats. It is widespread, commonly encountered, and exceedingly locally abundant (given sufficient precipitation) at mid elevation sites in Ilocos Norte (Brown et al. 2012). The population is believed to be stable.
This species inhabits high-elevation forests, which are relatively less threatened by habitat conversion and agriculture and human encroachment. Regardless, some subpopulations of this species are still subjected to habitat loss caused by small-scale shifting agriculture, expanding human settlements, wood collection for firewood and charcoal production, and illegal logging by commercial entities. In addition, the construction of a major east-west road was completed in 2016 through the western part of Isabela Province and the presence of the road is anticipated to intensify illegal logging activities (Philippines Red List Assessment Workshop May 2017). In addition, nickel, chromite and gold mining are taking place within the Northern Sierra Madre and the Central Cordillera, as well as limestone and sand quarrying (Philippines Red List Assessment Workshop May 2017). It is expected that this species will be highly vulnerable to climate change impacts due to desiccation of their fern microhabitats (Alcala et al. 2012).
Only a few protected areas are currently found in this region (as yet, though, there are no records from Pulag National Park).
There is a need for more effective management and protection of remaining tracts of intact lowland and montane rainforest in the Cordilleras.
More information is needed on this species' population size, distribution, and trends, and additional taxonomic research is recommended in light of the cryptic species present in this complex.
Red List Status
Listed as Least Concern in view of its relatively wide distribution, tolerance of a degree of habitat disturbance, and presumed large population.
This species is a taxonomic complex and contains several cryptic species (Philippines Red List Assessment Workshop May 2017).
IUCN SSC Amphibian Specialist Group 2018. Platymantis cornutus. The IUCN Red List of Threatened Species 2018: e.T17528A58473683. http://dx.doi.org/10.2305/IUCN.UK.2018-1.RLTS.T17528A58473683.en .Downloaded on 17 November 2018