This species seems to be limited to the Nguru Mountains, part of the Eastern Arc Mountains, Tanzania. Individuals were found in the Nguru South Forest Reserve, at elevations between 1,790 - 2,100 m asl. Its estimated extent of occurrence is equal to or less than 86 km2, while the estimated area of occupancy is about 41 km2 (Poynton et al. 2008). It has never been found outside this area or at higher altitudes within the reserve, despite extensive surveys within the Nguru and neighbouring mountains (M. Menegon pers. comm. November 2010).
Habitat and Ecology
The species is found in primary montane forest, bamboo and secondary forest including areas bordering agriculture. Individuals can be found in the leaf litter (Poynton et al. 2008). It is presumed to breed by direct development in common with other members of its genus, laying eggs in leaf litter (J. Poynton pers. comm. November 2010).
Currently the population density appears to be high (Poynton et al. 2008), and the species is widespread throughout its small range (M. Menegon pers. comm. November 2010).
This species is confined to a single location, which is under threat from timber extraction, clearance and burning for agriculture, cultivation of yams, and understorey clearance for cardamom production. At present these activities are mostly restricted to low elevations within and around the reserve (M. Menegon pers. comm. November 2010), but may in future threaten pristine areas where this species occurs. This is a species of mountain summits, whose inability to migrate to higher altitudes may render it vulnerable to the effects of climate change (Poynton et al. 2008).
It is found in a proposed nature reserve, Mkingu Nature Reserve, which comprises the previously named Nguru South and Mkindo Forest Reserves (S. Loader pers. comm. April 2012). Currently, enforcement of this protection is limited (S. Loader pers. comm. June 2011). Monitoring efforts are recommended for this species, and for the endemic Nguru montane amphibian community as a whole (Poynton et al. 2008; M. Menegon pers. comm. November 2010).
Red List Status
Listed as Vulnerable because all individuals are in a single location, and although there are no immediate threats, any future expansion of agricultural and logging activities into its habitat would justify a listing of Critically Endangered. In addition, its extent of occurrence is less than 100 km2.
IUCN SSC Amphibian Specialist Group, 2012. Arthroleptis nguruensis. The IUCN Red List of Threatened Species 2012: e.T176285A1437185. http://dx.doi.org/10.2305/IUCN.UK.2012-1.RLTS.T176285A1437185.en .Downloaded on 12 December 2018