This species is known only from the type locality: Torres, Rio Grande do Sul State, Brazil. The type locality is listed as a municipality, which has since been divided into several municipalities.
Habitat and Ecology
There is no information about its ecology or biology in the literature. It presumably breeds in water.
The species had not been recorded since 1960, until its recent rediscovery (one juvenile) in 2004 (Escobar et al. 2004).
There is no information on threats to this species, although there has been extensive habitat loss in its range due to urbanization in the last 30 years. The Coastal Atlantic Forest is considered to be one of the smallest and the most threatened ecosystems in Rio Grande do Sul (Fontana et al. 2003 in Escobar et al. 2004).
There are no protected areas near where this species was collected. It is categorized as Vulnerable on the Brazil national list.
Red List Status
Listed as Vulnerable because its Extent of Occurrence is less than 20,000 km2, it is known from fewer than ten locations, and there is continuing decline in the extent and quality of its habitat in Rio Grande do Sul, southern Brazil.
Débora Silvano, Paulo Garcia 2010. Melanophryniscus macrogranulosus. The IUCN Red List of Threatened Species 2010: e.T54823A11210082. http://dx.doi.org/10.2305/IUCN.UK.2010-2.RLTS.T54823A11210082.en