This species is known from isolated records from southern Cameroon, southern Congo, and eastern Democratic Republic of Congo. The type locality is an unspecified locality in Cameroon; there are more recent Cameroonian records attributed to this species from Mount Manengouba and from Mount Nkolodon near Yaounde. In eastern Democratic Republic of Congo, there are records from Virunga National Park (Laurent 1972) and from the town of Beni. Its occurrence in Gabon, Equatorial Guinea, and Central African Republic is not confirmed; attempts to map its distribution for this assessment however assume that it is found in the intervening areas between the known localities, in the forest zone north of the Congo River. Its elevational range is unknown, and its extent of occurrence (EOO) based on this mapping is 1,769,417 km2.
Amiet (pers. comm.) points out that this species, when better understood, might prove to be a montane species, in which case the attempts made at mapping its range so far are clearly wrong. In any case, the specimens from eastern Democratic Republic of Congo were never found in the field, and so their assignation to A. tuberosus is doubtful. It is also possible that animals from Cameroon currently referred to as A. adelphus are in fact A. tuberosus. The confusion surrounding this species will only be resolved by more fieldwork in the central African rainforests, with a particular focus on its calls which still needs to be done.
Habitat and Ecology
This is presumably a forest species, living on the forest floor in montane and perhaps lowland forests. It presumably breeds by direct development.
There is little information on its population, pending clarification of its taxonomic status. However, due to ongoing declines in the extent and quality of habitat, the population is suspected to be decreasing.
This species is expected to be threatened by forest loss due to agricultural development and logging.
This species is said to occur in Virunga National Park and probably also in other protected areas.
Research is required on the taxonomy, distribution, population status, habitat, ecology, use or trade, and threats to this species.
Red List Status
Data Deficient (DD)
Listed as Data Deficient since, although it has been recorded over a very wide area, there are only very few records (some of which a questionable), and there is still a lot unknown about its status and habitat requirements.
There are major taxonomic problems with the genus Arthroleptis through much of Africa. In many cases, the available names can be referred only to museum specimens, not to animals in the field. This is because the identification of these species frequently depends more on their vocalizations than their morphology. There is still a lot of taxonomic confusion particularly with this species (M.-O. Rödel pers. comm. July 2016), and specimens currently referred to as Arthroleptis adelphus might possibly belong to this species (J.-L. Amiet pers. comm.).
IUCN SSC Amphibian Specialist Group 2017. Arthroleptis tuberosus. The IUCN Red List of Threatened Species 2017: e.T54390A18365432. http://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T54390A18365432.en .Downloaded on 17 January 2019