This species has been found at sites along the road that runs from Ranomafana village to Mananjary on the coast and in the Ambolo forest fragment between 450-700 m asl in eastern Madagascar (Ndriantsoa et al. 2013). It may occur more widely and its range map includes Ranomafana National Park because it is suspected to also occur within its boundaries although it has not been recorded there (J.C. Riemann pers. comm. November 2014). Its extent of occurrence (EOO) is 1,329 km2.
Habitat and Ecology
It has been recorded in the leaf litter of forest fragments outside the Ranomafana National Park, some of which are adjacent to banana and coffee plantations (J.C. Riemann pers. comm. November 2014). Specimens have been found in partly degraded forest, where the shrub story was particularly dense, but the canopy was partly open. Another specimen was identified in the leaf litter at the bottom of a small valley in the Ambolo forest fragment. Two further specimens were located, both in degraded areas; one in the vicinity of a creek running through a mixed banana and coffee plantation, and the second was close to a rocky, almost dried up, creek near the forest edge (Ndriantsoa et al. 2013). It is likely that secondary, degraded, and opened up forest are only marginally suitable habitats, and that it requires a certain level of canopy cover to maintain moisture levels, which is a common trait for its congeners (F. Glaw pers. comm. November 2014).
The species' breeding strategy has not been confirmed, but is likely to be that of its congeners: terrestrial foam nests with non-feeding tadpoles.
Although found across a wide range of habitats, little is known about the presence of individuals outside of this small geographical range. While it has been found to be abundant at known sites, it is possible that it is a difficult species to detect (J.C. Riemann pers. comm. November 2014), and ongoing decline in the quality and extent of forest habitat suggests that its population trend could be decreasing.
While this species does seem resilient to a degree of habitat degradation, unprotected forest fragments in eastern Madagascar are few and disappearing fast. So the threats to the species including the ongoing decline in the extent and quality of its forest habitat due to subsistence agriculture, timber extraction, charcoal manufacturing, invasive spread of eucalyptus, livestock grazing, regular burning to maintain cattle pasture, expanding human settlements, and a recent increase in artisanal mining.
Despite ongoing, non-targeted surveys in the Ranomafana National Park, this species has not been recorded from any protected areas. However, it is very likely to occur in Ranomafana as the nearest record is only 3 km away from the Park boundary (J.C. Riemann pers. comm. November 2014).
Habitat protection and management of forest habitat is urgently needed in the face of ongoing threats.
Further research is required to better understand the species' population size, distribution and trends.
Red List Status
Listed as Endangered because its extent of occurrence (EOO) is 1,329 km2, it is known from fewer than five locations, and there is ongoing decline in the quality and extent of its habitat.
IUCN SSC Amphibian Specialist Group 2016. Rhombophryne miery. The IUCN Red List of Threatened Species 2016: e.T66390759A68304811. http://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T66390759A68304811.en .Downloaded on 13 December 2018