This species is known with certainty only from its type locality (Nosy Boraha) just off the east coast of Madagascar (Vences et al. 2013). Its distribution on the mainland is uncertain and confused with other species in the complex, although very likely (Vences et al. 2013). For the purposes of this assessment, although it does not show the real extent of its occurrence, we mostly follow the former concept with a broad distribution occurring from Montagne d'Ambre in the far north to the extreme south. However, records in the south from Andohahela are now attributed to Guibemantis annulatus and Guibemantis wattersoni and have been removed.
Habitat and Ecology
It is an arboreal species of rainforest, including degraded forest, where Pandanus occurs in the understorey. It has also been found in eucalyptus plantations, but not in open areas. It breeds in Pandanus leaf axils by larval development.
It is locally abundant where Pandanus occur. Due to extreme similarity with Guibemantis methueni, almost nothing is known about its population size. Its population is however suspected to be decreasing due to ongoing decline in the quality and extent of its habitat.
Its forest habitat is receding due to subsistence agriculture, timber extraction, charcoal manufacture, and invasive spread of eucalyptus, livestock grazing and expanding human settlements. The most important threat is the harvesting of Pandanus plants, which are used for the roofs of huts.
It occurs in several protected areas on the mainland.
Improved protection and management of forests throughout the region is required, including within the boundaries of protected areas.
Further research is required to clarify the species' distribution, population size and trends.
Red List Status
Least Concern (LC)
Listed as Least Concern in view of its wide distribution and presumed large population.
The taxonomy of this species is unclear, and it is likely that is a complex of several undescribed species (F. Andreone and M. Vences pers. comm.). It has been confused with Guibemantis albolineatus, and Guibemantis methueni has recently been removed from the synonymy of this species (Vences et al. 2015). Its southernmost range is now attributed to Guibemantis annulatus and Guibemantis wattersoni. Clarification of the complex and its distribution is therefore required.
IUCN SSC Amphibian Specialist Group 2016. Guibemantis bicalcaratus. The IUCN Red List of Threatened Species 2016: e.T79789864A79790033. http://dx.doi.org/10.2305/IUCN.UK.2016-1.RLTS.T79789864A79790033.en .Downloaded on 15 February 2019