A new genus of toad (Anura: Bufonidae) from the Republic of South Africa with remarks on its relationships Alice G. C. Grandison Department of Zoology, British Museum (Natural History), London SW7 5BD Hewitt (1926) described two small species of toads from the Cape Region of South Africa. He believed them to be closely related and distinguished them on the basis of size and the presence of an ear in the larger species, Bufo tradouwi. Both B. tradouwi and the smaller species, B. rosei, occur in the Cape Folded Mountain Belt, tradouwi being first described from the Swellendam Mountains and the Tradouw Pass at 1067-1676 m and rosei from the plateau above Muizenberg Mountain in the Cape Peninsula at 335 m, about 200 km to the west. In 1929 Power & Rose gave an account of the habits and life history of rosei, including a description of the eggs and tadpole. They stated that they believed rosei to be confined to the Cape Peninsula and quoted the vertical distribution of the species as 244 m at the southern tip of the Cape Peninsula, to 1006 m on Table Mountain. They referred to a juvenile collected at a band of shale at 1067 m in the Cedarberg Mountains (about 200 kms NNE of the Peninsula) as resembling rosei except for an indistinct tympanum being present and suggested that it may 'be a link between B. rosei and B. tradouwi'. No further published reports appeared on these taxa until in 1964 Poynton synonymized them, believing that intraspecific variation could account for the loss of ear elements in rosei. Tandy & Keith (1972) resurrected tradouwi and, along with B. gariepensis Smith, B. inyangae Poynton and B. amatolica Hewitt placed it with the angusticeps Smith group, a group restricted to extreme Southern Africa and distinguished by them as 'small to medium sized toads having smooth skins, hypertrophied testes with a peculiar biochemical effect on eggs of other species when squashed and used in artificial crosses'. They placed B. rosei in a separate group but mentioned that its smooth skin and hypertrophied testes and its detailed anatomy and distribution in relict populations on mountain summits of the Cape Peninsula and Cape Folded Mountains suggest a closer affinity to the angusticeps group than to the earless Bufo taitanus Peters which they felt bore a superficial resemblance to rosei. Their reference to its detailed anatomy was not further explained nor did they elaborate on its resemblance to B. taitanus. The only published work on the osteology of B. rosei is one short paragraph (Martin, 1972) in which three dermal skull elements are described. Like Tandy & Keith I could not accept Poynton's synonymising tradouwi with a species that in lacking middle ear elements has undoubtedly different ecological requirements, a different behavioural pattern as well as a more derived morphology. As part of my ongoing research into the comparative morphology of the osteocranium, vertebrae and myology of African bufonids material identified as rosei and tradouwi was examined. Results demon-strate that tradouwi is indeed distinct from rosei, that they are clearly distinguishable from each other by both external and internal morphological characters and that they are allopatric montane species with different but perhaps overlapping vertical distributions. They are separated geographically by the deep gap, the Nuwe Kloof, which divides the Bains Kloof Mountains from the Great Winterhoek Mountains, and by the Valley of the Breede River which stretches from the Tulbagh/Worcester valley southeastwards to Witsand on the south coast. Bufo rosei is confined to the area south west of this barrier, Bufo tradouwi to the Cape Folded Mountains to the north and east. The suite of characters possessed by tradouwi and rosei suggests that these Cape taxa are early derivatives from a stock that also gave rise to Bull. Br. Mus. nat. Hist. (Zool.) 39 (5) : 293-298 Issued 1 8 December 1 980
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