This species is known only from the type locality, São João da Graciosa, Serra do Mar in the state of Paraná, Brazil. It has an altitudinal range of 50-150m asl.
Habitat and Ecology
It occurs in fast-flowing rocky streams in lowland forest and it reproduces in streams.
The population is unknown. It has not been collected since the original collection in the late 1970s.
The major threats are unknown. It is possibly threatened by tourism. Some other Cycloramphus species have declined for unexplained reasons, and so it is an urgent priority to rediscover populations of this species.
It occurs in Serra da Graciosa State Park. The creation of new protected areas and research actions are needed. Given the declines of high-altitude stream-breeding species in other parts of the wet tropics, surveys are urgently needed to relocate this species and to assess its status, especially in view of the lack of recent records.
Débora Silvano 2004. Cycloramphus rhyakonastes. In: IUCN 2014