This species is known from 131–1,390 m Asl within Chiang Mai, Phetchabun and Loei Provinces, Thailand (Taylor 1962, Ohler et al. 2011), Khammouan, Xaignabouli, Savannahket and Luang Prabang Provinces, Lao PDR (Ohler et al. 2011), and Dien Bien, Son La and Hoa Bin Provinces, Viet Nam (Pham et al. in press). 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 other provinces in all three countries. Further surveys in these areas may uncover its presence, therefore its range has been projected beyond known sites to include these areas of suitable habitat. The species' estimated EOO is 455,171 km2, which consists of six threat-defined locations.
Habitat and Ecology
This species is associated with small to moderate streams in hilly evergreen forest (Ohler et al. 2011). Reproduction occurs around July-August, when males accompany their advertisement calls with a visual signaling component whereby the orange upper forelimbs are exposed (Ohler et al. 2011). Males are also reported to exhibit territorial behaviours when reproductively active (Ohler et al. 2011). Tadpoles inhabit stream-side pools without current and are nocturnally active, hidden under leaves during the day (Ohler et al. 2011). This species is not known to occur sympatrically with any congeners. Parts of this species' habitat have been observed to be degraded due to deforestation (Ohler et al. 2011).
Very little is known about this species' population size, except that it was described from 83 individuals: 40 from Lao PDR and 43 from Thailand (Ohler et al. 2011), and was subsequently detected again in series of surveys over northern Viet Nam (Pham et al. in press). Some population declines are likely for this species due to the effects of forest loss (Ohler et al. 2011), however further surveys would be needed to determine their severity and the species' true abundance.
Rapid expansion of agriculture and associated forest loss is ongoing throughout Laos, Thailand and Vet Nam, and has been identified as a key threat to biodiversity in the region (Sodhi et al. 2010). Deforestation has been observed in parts of this species' known habitat and is probably affecting its population (Ohler et al. 2011).
This species has been recorded in Doi Suthep, Doi Inthanon, Doi Chiang Dao and Phu Kradung National Parks, Thailand (Ohler et al. 2011), as well as Copia, Sop Cop, Muong Nhe and Ngoc Son-Ngo Luong Nature Reserves, Viet Nam (Pham et al. in press). Its estimated range also spans parts of an extensive series of other protected areas in Thailand, Laos, and Viet Nam.
Addressing the lack of data is the first step towards ensuring this species' long-term persistence; further research on its range, threats, and the size and trends of its population would inform conservation decisions.
Red List Status
Least Concern (LC)
Listed as Least Concern as this species is relatively widespread, with an estimated extent of occurrence (EOO) of 455,171 km2.
Removed from the synonymy of Leptolalax oshanensis by Ohler et al. (2011) where it had been placed by Dubois (1981).
IUCN SSC Amphibian Specialist Group 2017. Leptolalax minimus. The IUCN Red List of Threatened Species 2017: e.T48101848A48101855. http://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T48101848A48101855.en .Downloaded on 20 January 2019