This species is known only from Casa Ypiranga in the Serro do Mar, near Morretes, in the state of Parana in southern Brazil, at around 600m asl. The type series was collected along the Curitiba-Paranagua railway.
Habitat and Ecology
The type series was collected in crevices and cracks in the vertical cliffs along the railway. If it is like other species of Cycloramphus, the larvae live on rocks in the splash zones of waterfalls and streams in rocky areas in and around forest.
It is known only from the type series, and searches since 1982 have failed to find any individuals.
It might be impacted by tourism.
It possibly occurs in Parque Estadual Pico do Marumbi, but this needs to be confirmed. 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. Some other Cycloramphus species have declined for unexplained reasons, and so it is an urgent priority to rediscover populations of this species.
Vanessa Verdade, Magno Vicente Segalla 2004. Cycloramphus duseni. In: IUCN 2014