This species is endemic to Sri Lanka and is currently known from three locations: Kanneliya-Dediyagala-Nakiyadeniya (KDN Complex; 201.39 km2), Kitulgala, Kottawa Forest Reserve (0.15 km2), and the Sinharaja World Heritage Site (85.64 km2) (Meegaskumbura et al. 2009, M. Meegaskumbura pers. comm. November 2010). These forest patches add up to nearly 290 km2, but are believed to be in decline both in extent and habitat quality due to agricultural encroachment, invasive plant species and pollutant effects. It is also quite possible that this species may occur in other rainforest patches in the wet-zone lowlands of Sri Lanka (Meegaskumbura et al. 2009, M. Meegaskumbura pers. comm. October 2010). It is known to occur between 60 and 513 m asl (Meegaskumbura et al. 2009).
Habitat and Ecology
This species occurs in lowlands and mid-elevation rainforests and is restricted to primary and secondary forests with extensive canopy cover (Meegaskumbura et al. 2009), suggesting that it has a low tolerance threshold towards habitat disturbance. Individuals can be found perching on leaves of shrubs that they climb at night to vocalize (Meegaskumbura et al. 2009). Males have been observed 0.5-1.5 m above ground level (Meegaskumbura et al. 2009). This species breeds by direct development, where eggs are laid in a depression in the soil and the female covers it up later (M. Meegaskumbura pers. comm. October 2010).
Although the species' distribution within canopy-covered forest is not uniform, it is considered to be common where it is found (M. Meegaskumbura pers. comm. October 2010). It is believed to be a forest-dependent species, so it is thought that its dispersal ability would be severely hindered by forest fragmentation, which has occurred in its former habitat (M. Meegaskumbura pers. comm. November 2010).
There are tea plantations surrounding most parts of these reserves, and encroachment of all the forest reserves by tea growers, as well as associated use of biocides and fertilizers, has led to a reduction of this species' AOO as well as the quality of its habitat (M. Meegaskumbura pers. comm. November 2010). The tourism industry has also experienced considerable development in these areas, but its effects still remain poorly understood.
This species occurs within the Kottawa, Kitulgala, Sinharaja and Kanneliya-Dediyagala-Nakyadeniya Forest Reserves; however, agricultural encroachment and pollutant runoff suggest that reserve boundaries require reinforcement. No conservation actions are currently known for this species, but it does receive some indirect protection in the form of prevention of illegal tree felling within forest reserves (M. Meegaskumbura pers. comm. October 2010). More information is needed on this species' distribution, population status and natural history.
Red List Status
Listed as Endangered because its area of occupancy (AOO) is estimated to be around 290 km2 and declining, its distribution is severely fragmented, it is known from only three locations, and the extent and quality of its forest habitat in Sri Lanka is declining.
IUCN SSC Amphibian Specialist Group 2011. Pseudophilautus singu. The IUCN Red List of Threatened Species 2011: e.T187831A8636525. http://dx.doi.org/10.2305/IUCN.UK.2011-1.RLTS.T187831A8636525.en .Downloaded on 19 January 2019