This species is known from 1,000–1,550 m Asl in Dak Lak and Khanh Hoa Provinces, south-central Viet Nam (Poyarkov et al. 2014). These are unlikely to represent the actual limits of the species' range as similar habitat and elevations to those in its known localities occur in adjacent parts of the Annamite Mountains including northern Lam Dong and Ninh Thuan Provinces, and southwestern Dak Nong Province. Further surveys in these areas may uncover its presence there (Poyarkov et al. 2014), therefore its range has been projected beyond known sites to include these areas of suitable habitat. The species' extent of occurrence (EOO) is 7,964 km2, which consists of one threat-defined location.
Habitat and Ecology
This species is associated with mixed evergreen forest on mountain slopes and ridges (Poyarkov et al. 2014). Reproduction begins during the rainy season, which varies temporally across the species' range; breeding has been observed in late March and mid-June in Dak Lak and Khanh Hoa Provinces, respectively (Poyarkov et al. 2014). This species is a phytotelm breeder, and clutches of up to 30 eggs are deposited on the inner walls of water-filled tree holes above the waterline. Upon hatching, the larvae fall into the water, where they remain until metamorphosis (Poyarkov et al. 2014).
Little is known about the size and trends of this species' population except that eight adults from Dak Lak, and five adults, 12 larvae and several egg clutches from Khanh Hoa were collected for the description of the species (Poyarkov et al. 2014). This species' population is likely in decline as deforestation continues to affect its range (Poyarkov et al. 2014). Further surveys are needed to determine its relative abundance.
This species is threatened by habitat loss due to the effects of logging and the encroachment of other anthropogenic processes within its range (Poyarkov et al. 2014). Due to its restriction to high-altitude areas, the species may also be at risk of disturbance by alterations to its habitat associated with climate change.
This species is known to occur in two protected areas (Chu Yang Sin and Hon Ba Nature Reserves) (Poyarkov et al. 2014). Additional protection of parts of its range may be warranted to mitigate declines.
Addressing the lack of data is the first step towards ensuring this species' long-term survival; research should be carried out to determine its true range, relative abundance, and threats.
Red List Status
Listed as Vulnerable as this species' EOO is 7,964 km2, it is known from one threat-defined location, and there is a continuing decline in the extent and quality of its habitat.
IUCN SSC Amphibian Specialist Group 2017. Microhyla arboricola. The IUCN Red List of Threatened Species 2017: e.T73727593A73727604. http://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T73727593A73727604.en .Downloaded on 16 December 2018