Amietia vertebralis (Hewitt, 1927)
A. vertebralis was previously classified Restricted (Branch 1988). It was subsequently discovered at a number of additional localities, especially in the highlands of Lesotho (Bates 2002), and it appears to be abundant in many parts of its range (e.g. Lambiris 1988b). The species was reassessed and assigned to the category of Least Concern (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).
Adults can apparently remain submerged for a few days at a time (Bush 1952) because they are able to breathe efficiently through their skin, whereas juveniles spend more time foraging at the edge of the water (Lambiris 1988b). Both adults and tadpoles have been observed moving about under ice during winter and are intolerant of high temperatures (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).
Lambiris (1988b) describes the tadpole is adapted to life in fast-flowing water in having a wide, flat body, a heavy but narrowly-webbed tail, and a large sucker-like mouth for obtaining a firm grip on smooth rocks. Tadpoles initially prey on infusoria, and later scavenge on detritus (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).
Bates (2002)recorded that A. vertebralis is found at high altitudes in Lesotho and adjacent mountain ranges in KwaZulu-Natal, Free State and Eastern Cape Province of South Africa, including the Witteberg range (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).
This species inhabits Afro Montane Grassland and Alti Mountain Grassland of the Grassland Biome, usually at altitudes of 1750–3282 m. These frogs occur in cold, clear streams and associated pools with rocky substrates, in mountainous areas, including most major rivers and their tributaries in Lesotho. A. vertebralis is largely aquatic, but may be found on rocks and under stones or amongst vegetation at the water’s edge (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).
Breeding occurs from mid-September to February (Lambiris 1988b). Males usually call while almost completely submerged, with only the head protruding from the water, but occasionally they call from exposed rocks (Channing 1979). The eggs are attached to submerged vegetation in shallow, gently-flowing streams or associated pools with sandy or stony substrates (Lambiris 1988b, 1989a). Van Dijk (1996) observed eggs in shallow, slow-flowing water in September and late November in central Lesotho (Text from Minter et al., 2004, © SI/MAB Biodiversity Program).