This species is currently known only from 440-1,300 m asl on the eastern flank of Phnom Samkos, Pursat Province, in the Cardamom Mountains of Cambodia, (Grismer et al. 2007, T. Neang pers. comm. October 2015). This is unlikely to represent the actual limits of the species' range as similar habitat and elevations to those in its known locality occur in adjacent parts of Baat Dambang, Koh Kong, and Kampong Spueu Provinces, therefore its range has been projected beyond known sites to include these areas of suitable habitat. Further surveys in these areas may uncover its presence there, though it is possible that the species' ability to disperse throughout the mountain range is limited by the fact that it probably cannot reproduce in particularly steep terrain (where temporary pools would not easily form). The species' estimated extent of occurrence (EOO) is 11,234 km2, which represents two threat-defined locations.
Habitat and Ecology
This species is associated with hilly evergreen forest (Grismer et al. 2007). Individuals have been found adjacent to temporary rain pools about 1.5 m above the ground on small shrubs among grassy vegetation (Grismer et al. 2007, T. Neang pers. comm. October 2015). The species appears to breed mostly on forest edges, where it deposits jelly masses of around 50 eggs in vegetation overhanging temporary rain pools (T. Neang pers. comm. October 2015). Parts of the species' habitat has been cleared for agriculture, and it has been observed along man-made paths and even breeding in puddles along them (T. Neang pers. comm. October 2015). It is unclear whether such habitat alteration has a considerable effect on it. The quality of habitat within the species' range appears to be in decline due to the effects of human transportation and logging (Bradfield and Daltry 2009, L. Grismer pers. comm. January 2008), however the species' apparent preference for breeding in grassy areas on paths and forest edges may indicate some level of tolerance to moderate disturbance (T. Neang pers. comm. October 2015).
Little is known about the size or trends of this species' population except that some breeding assemblages of around 10 individuals and egg masses have been observed throughout its range (T. Neang pers. comm. October 2015). The species has been described as uncommon (J. Holden pers. comm. March 2012), but whether the few observations of this species reflects true rarity is unclear. Habitat disturbance associated with agriculture, the illegal removal certain tree species, and the development of a road within the species range (Bradfield and Daltry 2009, L. Grismer pers. comm. January 2008) may cause population declines, however the extent of this is uncertain.
A high rate of forest loss has been identified as a significant threat to biodiversity throughout Cambodia (Sodhi et al. 2009). Recent satellite imagery shows some areas of cleared land scattered throughout this species' range. A major cause of habitat loss in the Cardamom Mountains (including within Phnom Samkos Wildlife Sanctuary) is the illegal removal of certain tree species for the harvest and refinement of safrole oil - a precursor to the production of elicit narcotics including methylenedioxymethamphetamine (known commonly as ecstasy) (Bradfield and Daltry 2009). This species' type-locality is described as heavily affected by logging (J. Holden pers. comm. March 2012) and parts of its range have been cleared for agriculture (T. Neang pers. comm. October 2015). A wide road was also developed directly through its range in around 2008 (L. Grismer pers. comm. January 2008). However there is considerable uncertainty as to whether such disturbances are affecting the species' population, as it has been observed breeding in affected environments (T. Neang pers. comm. October 2015). Several observations of parasitism on the species have been observed where arthropods (possibly Diptera) deposited eggs into the frogs' egg masses. The insect larvae presumably sequestered nutriment from the frog eggs as infected masses yielded no young (T. Neang pers. comm. October 2015). Research is warranted to determine whether this constitutes a threat to Chiromantis samkosensis and other amphibians with a similar reproductive strategy.
This species is known from Phnom Samkos Wildlife Sanctuary (L. Grismer pers. comm. January 2008). Its predicted range also includes parts of Aural Wildife Sanctuary and Botum Sakor National Park, so it may also be occur there.
In order to ensure the species' long-term survival, the lack of data must be addressed.
Research should be carried out to determine its distribution, relative abundance, life history and threats.
Red List Status
Listed as Vulnerable as this species' estimated extent of occurrence (EOO) is 11,234 km2, representing only two threat-defined locations, and there is also an ongoing decline in the quality of its habitat.
IUCN SSC Amphibian Specialist Group 2016. Chiromantis samkosensis. The IUCN Red List of Threatened Species 2016: e.T136075A47152734. http://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T136075A47152734.en .Downloaded on 23 February 2019