Amietia inyangae (Poynton, 1966)
Original Published Description:
Inyanga River Frog (English)
Amietia inyangae is a restricted range endemic known from the eastern montane region of Zimbabwe, on Inyangani Mountain and within Chimanimani National Park. This anuran is limited in distribution to the Eastern Zimbabwe montane forest-grassland ecoregion. Adults of the species are characteristically found in the vicinity of rock armored, rapid velocity streams in montane grassland. This river frog population is classified as endangered, and its numbers are considered in decline.
Amietia inyangae is known from the eastern montane region of Zimbabwe, on Inyangani Mountain and within Chimanimani National Park. This anuran is endemic to the Eastern Zimbabwe montane forest-grassland ecoregion. (World Wildlife Fund & Hogan. 2008) It has only been recorded above 2000 meters in elevation. Poynton considers the frog likely to exist across the border in Mozambique, but there have not yet been any such Mozambique observations of the species. (Poynton. 2004)
A. inyangae is the only river frog found north of the Limpopo River which has a tympanum that is less than one half the diameter of the eye. The only other river frog north of the Limpopo is A. angolensis, which species has tympanum more than one half the eye diameter (Du Preez & Carruthers, 2009).
Diagnostic features of the A. inyangae tadpole include the absence of an elygium or umbraculum on the eye. A diagnostic range descriptor is that the tadpole is not found on the high-lying parts of the Drakensberg. Diagnostic features of the labial teeth require the tadpole to have three or four labial tooth rows in the lower jaw and four in the upper jaw. The tail fin is broad, reaching its deepest point two thirds down toward the tail, and the tail tapers to a rounded tip. A very close resemblance is to the tadpole of A. angolensis, whose lower jaw has three labial teeth rows and tail tapers to a well defined point (Du Preez & Carruthers, 2009).
As with most Ametia species, the rear one-fifth of the tadpole tail is usually not totally dark, but partially diaphanous. The spiracle is constricted, and there is usually no spur on the developing foot (Du Preez & Carruthers, 2009).
Habitat and Ecology
Adult A. inyangae are found in the vicinity of rock armored, rapid velocity streams in montane grassland. Adults have been also found sitting on rock ledges behind waterfalls, or on rocks protruding from the midst of rapids; juveniles typically frequent quieter backwaters. Eggs are characteristically deposited by the female in shallow rocky pools (Poynton, 2004).
There are a number of other anurans that co-inhabit with A. inyangae the Eastern Zimbabwe montane forest-grassland grassland ecoregion, to which A. inyangae is endemic. These anurans include Tschudi’s African Bullfrog (Pyxicephalus adspersus), Striped Frog (Rana fasciata), Silver-banded Banana Frog (Hyperolius tuberilinguis), Kihengo Screeching Frog (Arthroleptis stenodactylus), and the Chirinda Screeching Frog (Arthroleptis xenodactyloides; World Wildlife Fund & Hogan, 2008).
IUCN Red List Category and Justification of Conservation Status
Listed as Endangered on the IUCN Redlist, chiefly due to its extent of occurrence (less than 5000 square kilometers and area of occupancy of less than 500 square kilometers), with all A. inyangae individuals sighted in fewer than five locations, and an ongoing decline in the extent and quality of its habitat (Poynton, 2004).
Although the high-elevation habitat of A. inyangae has been retained as somewhat intact up until present, there are continuing future threats to the species habitat from conversion of native forest to timber plantations, as well as overgrazing by domesticated livestock, and more intense human settlement (Poynton, 2004).
- Rana johnstoni inyangae Poynton, 1966 (synonym)
- Afrana inyangae — Visser and Channing, 1997 (synonym)
- Amietia inyangae — Frost, Grant, Faivovich, Bain, Haas, Haddad, de Sá, Channing, Wilkinson, Donnellan, Raxworthy, Campbell, Blotto, Moler, Drewes, Nussbaum, Lynch, Green, and Wheeler, 2006 (synonym)