Family Brevicipitidae

Breviceps sopranus Minter, 2003

Whistling Rain Frog, Fluitende Blaasoppadda (A)

By L.R. Minter

Currently accepted name: Breviceps sopranus
Red listing status: Data Deficient

Photo by Douglas M, 2012. URL: FrogMAP: 466

Red List Species

Status: Data Deficient (DD)

Identification

The males of B. sopranus range from 22–26.2 mm (N = 14) in body length. Morphologically, the species is difficult to separate from B. mossambicus and B. bagginsi, but can be easily distinguished from all Breviceps species by it’s advertisement call, a series of long, unpulsed, high-pitched whistles. Each calls varies from 0.6–1.98 s in duration and from 2755–3468 Hz in frequency (N = 20; Minter 2003).

Distribution

B. sopranus is known only from the atlas region at present, but may also occur in southern Mozambique. It has been recorded as far south as Mtunzini (2831DD) in KwaZulu-Natal, and it follows the Lebombo Mountains northward along the eastern border of Swaziland to Komatipoort (2531BD) in Mpumalanga (Passmore and Carruthers 1995; Minter 1998, 2003).

The atlas data are accurate but incomplete. The unusual call may easily be mistaken for that of an insect or bird, particularly when heard during the day. This may have contributed to the paucity of distribution data.

Habitat

B. sopranus inhabits a variety of vegetation types within the Forest and Savanna biomes: it is found in the dense, herbaceous undercover of the Sand Forest at St Lucia and Dukuduku, Afromontane Forest on the northern slopes of the Lebombo Mountains at Jozini, and the sandy rhyolitic soils of the Lebombo Arid Mountain Bushveld at Mlawula Nature Reserve (Swaziland) and Komatipoort (Minter 1998, 2003).

At St Lucia, B. sopranus occurs in forest while B. mossambicus occupies the open grassy areas between forest patches. In bushveld habitats, B. sopranus occurs in sympatry with B. adspersus.

Life history

Breeding takes place between early October and early January. Choruses develop at any time of day, during light to heavy rain, but unless this is followed by drizzle or heavy mist, cease immediately afterward. Calling males often take up elevated positions on fallen branches or small plants, or call from the soil surface (Minter 1998, 2003). Amplexus and oviposition have not been observed.

Conservation

Status

B. sopranus is a recently described species (Minter 2003). Since the distribution and biology of this species are poorly known, an accurate assessment of its conservation status is not possible at present. It is therefore assigned to the category “Data Deficient”. The species occurs in the Hluhluwe and Mkuze Game Reserves and the Greater St Lucia Wetland National Park in South Africa, and the Mlawula Nature Reserve in Swaziland.

Threats

Outside of these protected areas much of the natural habitat of this species has been destroyed by the farming of crops such as sugarcane, and by deforestation in the Dukuduku forest.

Conservation actions

Distribution, life history and ecological data are urgently needed in order to adequately address the conservation needs of this species.

Current distribution map

Undated records;  pre-1996;  1996 to 2002;  2003 to present