This species is currently known from between 850–1,401 m Asl in Quang Nam (Bain and Nguyen 2002, J. Rowley unpubl. data), Thua Thien-Hue (Bain et al. 2007), and Gia Lai Provinces (Inger 1999), central Viet Nam. These are unlikely to represent the actual limits of the species' range as similar habitat and elevations to those in its known localities extend north to Quang Tri Province, east almost to the coast, and west to northeastern Cambodia and southeastern Lao PDR. Further surveys may uncover its presence these areas, therefore its range has been projected beyond known sites to include these areas of suitable habitat. The species' estimated EOO is 46,164 km2, which represents eight threat-defined locations.
Habitat and Ecology
This species is associated with rocky streams and herbaceous riparian vegetation in montane primary forest (J. Rowley, unpubl. data, Bain et al. 2007). Little else is known about this species' life history, however it presumably deposits eggs in streams and has an aquatic, free-living larval stage as do other Leptolalax for which the reproductive strategy is known. Calling occurs in July (Rowley et al. 2010) and one individual has been observed calling from vegetation 1 m above the ground adjacent to a cascading stream (Bain et al. 2007). Most observations of the species have occurred in undisturbed forest (J. Rowley, unpubl. data), possibly indicating some dependence on undisturbed habitat, however Bain et al. (2007) did record the species in disturbed forest.
Very little is known about the size and trends of this species' population, except that 17 individuals were collected in Gia Lai Province prior to its description (Inger et al. 1999). Additional individuals were collected in Quang Nam Province in 2002 (Bain and Nguyen 2002), in Thua Thien-Hue in 2005 (Bain et al. 2007), and in Quang Nam in 2007, when it was noted that several other males could be heard calling (J. Rowley, unpubl. data). The species appears to be difficult to detect, with observations within its range uncommon (J. Rowley pers. comm. October 2015). This species' population is likely in decline due to forest clearing for agricultural practices that are ongoing throughout parts of its range.
No major threatening processes have been identified as affecting this particular species. However habitat loss and degradation, particularly as a result of the conversion of forest to agricultural land to grow cash crop plantations (e.g. rubber, coffee and tea), is an ongoing threat throughout the Central Highlands (Meyfroidt and Lambin 2008, Meyfroidt et al. 2013). Areas of land cleared for agriculture are scattered throughout parts of the its predicted range (J. Rowley pers. comm. October 2015) and these could potentially affect the species.
This species is known from Ngoc Linh Nature Reserve (Bain and Nguyen 2002) and Song Thanh Nature Reserve (J. Rowley unpubl. data). Its estimated range also spans parts of other protected areas both in Viet Nam and Lao PDR.
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 46,164 km2, which represents eight threat-defined locations.
IUCN SSC Amphibian Specialist Group 2017. Leptolalax tuberosus. The IUCN Red List of Threatened Species 2017: e.T57576A113957447. http://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T57576A113957447.en .Downloaded on 20 January 2019