The species is only known from Nosy Mangabe island off the north east coast of Madagascar next to the town of Maroantsetra. These specimens were collected in 2005, ca. 50–100 m above sea level (Glaw et al. 2010). It is only known from one threat-defined location, and it has a restricted range with an extent of occurrence of 6 km2.
Habitat and Ecology
The species inhabits primary low-altitude rainforest, where it buries deep into the leaf litter. Only smaller adults and juveniles were found on the forest floor during the day, adults remained hidden in the litter whilst calling (Glaw et al. 2010). It presumably breeds by larval development and has non-feeding tadpoles, similar to other species in Cophylinae. It may reproduce in burrows within the leaf litter (M.D. Scherz pers. comm. November 2015).
It is only known from 13 specimens collected in 1991 and 2005 at Nosy Mangabe Island. The population is thought to be stable.
This island forest habitat is well protected and there are currently no threats to the species (A. Rakotoarison & M.D. Scherz, pers. comm.). However Batrachochytrium dendrobatidis has been confirmed in Madagascar and could pose a serious threat to this species if it is found to be susceptible to the disease.
The species occurs in Nosy Mangabe Special Reserve.
Research is required on ecology, especially its breeding behaviour (M.D. Scherz pers. comm. November 2015).
Red List Status
Listed as Vulnerable D2 because its range is restricted to Nosy Mangabe island, which has an extent of occurrence (EOO) of only 6 km2, and there is a potential future threat of Bd. Bd has been confirmed in Madagascar, and if this species is found to be susceptible to the disease then the entire population would be at risk in its very small, restricted range.
IUCN SSC Amphibian Specialist Group 2016. Rhombophryne mangabensis. The IUCN Red List of Threatened Species 2016: e.T49581234A49581242. http://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T49581234A49581242.en .Downloaded on 23 January 2019