Listed as Critically Endangered Possibly Extinct. Despite surveys efforts in suitable habitat over several decades, there are no records of the species since the late 1970s. It is, therefore, inferred that the species is either possibly extinct or if there is still an extant population, that it is very small (<50 mature individuals). However, additional sampling effort is needed before it can be declared Extinct or re-assessed under a different criterion.

This Brazilian endemic species is known from the type locality in the municipality of Petrópolis, and has also been found in Guapi, Mirim, Nova Friburgo and Teresópolis municipalities, across Serra dos Órgãos, Rio de Janeiro State (Wandolleck 1907, Bokermann 1966, Heyer 1983). It has been recorded between 800-1,200 m asl. The extent of occurrence (EOO) of the historical distribution is 591 km².

Similar to some of its congeners, this species was abundant where it occurred until the 1970s. The last specimens collected and deposited in a museum are from 1978 (A. Sabbag pers. comm. 2021).

Serra dos Órgãos is one of the most surveyed areas of Brazil. Because it was considered to be common and easy to detect, but no more records of this species have been made, it is considered possibly extinct. Sampling using environmental DNA (eDNA) techniques did not detect the species. During these analyses, DNA from a species of an unknown Cycloramphus was detected from samples taken in the Serra dos Órgãos; however, since there is no reference tissue collection associated to this species, it is not possible to determine that the sample belongs to Cycloramphus ohausi (Lopes et al. 2020, Lyra et al. 2020, D. Baêta pers. comm. 2021). 

The apparent disappearance of this species, even from areas of suitable habitat, is consistent with drastic declines caused by chytridiomycosis. Since this species has not been seen since the 1950s, despite extensive searches in its habitat, it is considered to be possibly extinct. If a relictual population persists, it probably consists of fewer than 50 mature individuals.

This is a terrestrial Cycloramphus species of the Atlantic Forest biome. It was collected from leaf-litter in rainforest. It is unknown whether it is associated with waterbodies or not, as there are both types of species in this genus.

Although the causes of suspected historical declines are not understood, infections of the amphibian fungal pathogen Batrachochytrium dendrobatidis (Bd) could be one of the causes (Brazilian Red List Assessment Workshop 2021).

Satellite imagery of the species' distribution shows evidence of habitat conversion, fragmentation, and degradation caused by crop cultivation, livestock grazing, forestry all of which are expanding due to a growing human population in the area even up to the ridges of the mountain. The use of fire to clear forest and maintain agricultural land is also a threat. These are major threats to the habitat outside the Parque Nacional da Serra dos Órgãos. Within the boundaries of the Parque, the threat would be fire and irregular occupation of the park boundaries (Brazilian Red List Assessment Workshop 2021).

There are no records of the species being utilized.

Conservation Actions In-Place
The species is confirmed only from the Parque Nacional Serra dos Órgãos and Petrópolis Environmental Protection Area, which would be equivalent to about 20% of its distribution. This species is included in the National Action Plan for the Conservation of Threatened Herpetofauna (Machado et al. 2021).

Conservation Needed
If an extant subpopulation is located, the possibility of a captive breeding programme should be considered to support the recovery of the species.

Research Needed
More exhaustive searches for this species are needed, in order to determine whether or not it still survives in the wild. If these surveys fail to locate the species in the coming 5-10 years, the species should be considered for an Extinct listing. If it is found, then further conservation measures, including a conservation management plan, will be needed.