This species is known from the East Usambara Mountains (including the Magrotto ridge), at 200-1,000 m asl, in northeastern Tanzania. Taking range as a proxy for extent of occurrence (EOO), this is estimated to be 635 km2. It is considered to occur in two threat-defined locations (S. Loader and J. Vonesh pers. comm. June 2012).
Habitat and Ecology
It is associated with rocky streams in montane forests, and is generally confined to mature forest although it has also been found in a tea estate (J. Vonesh pers. comm June 2012). It lays its eggs on rocks close to torrential streams and waterfalls. The larvae remain attached to the rocks, where they develop. When not breeding, the adults can be found on the forest floor, in holes on the ground, and in rock crevices.
It is common in suitable habitat. Its population is not considered to be severely fragmented (S. Loader pers. comm. June 2012).
This species is adversely affected by general encroachment and degradation of the forest caused by small-scale agriculture, rural settlements, pole cutting and logging, and it could also be affected by siltation of streams. A potential future threat might be the fungal disease, chytridiomycosis, since the related species, Petropedetes yakusini, has been shown to carry this fungus.
It occurs in the Amani, Nilo and Mkingu Nature Reserves, but there is a need for expanded and strengthened protection of forests in the Usambara Mountains. More information is needed on its population status and ecology. The species also requires close population monitoring, particularly given the possible threat of chytridiomycosis. Taxonomic research is needed to clarify the biological identity of this species.
Red List Status
Listed as Endangered because its extent of occurrence (EOO) is estimated to be 635 km2, it is known from two threat-defined locations, and the extent of its forest habitat on the East Usambara is declining.
Molecular data suggest that there are more than one species under this name (Loader et al. 2013).
IUCN SSC Amphibian Specialist Group 2013. Arthroleptides martiensseni. The IUCN Red List of Threatened Species 2013: e.T58064A17194471. http://dx.doi.org/10.2305/IUCN.UK.2013-2.RLTS.T58064A17194471.en .Downloaded on 19 November 2018