Evidence for an Afrotemperate amphibian fauna

Abstract

Latitudinal and altitudinal changes in composition of the African amphibian fauna is analysed to test the standard zoogeographical division of the continent into Palaearctic and Afrotropical Regions. A comparably high faunal change north and south of the. tropical savannas suggests that it is inappropriate to classify the south-temperate fauna as “Afrotropical”. High geographical turnover between lowland and montane faunas north of the Cape likewise suggests the inappropriateness of classifying the fauna of the Afromontane archipelago as “Afrotropical”. Although extending into the cartographic tropics, the area occupied by the temperate amphibian fauna lies outside the climatic tropics and covers the same general area as the Afrotemperate flora. This supports a division into three regions: Palaearctic, Afrotropical (in a restricted sense) and Afrotemperate. Account has to be taken of extensive transition zones between areas occupied by tropical and temperate amphibian faunas, and the Nile Delta is considered to show the typical features of a transition zone rather than be included in the Palaearctic Region as is usually done. Taxonomic differences are evident between faunas of East and West Africa, most marked in forest habitats, yet it seems acceptable to include non-Afromontane east and west faunas in a single Afrotropical Region. Reptiles, birds and mammals do not show a tripartite Palaearctic-Afrotropical-Afrotemperate pattern as strongly as amphibians. This is not unexpected considering global distribution patterns. The amphibian pattern agrees with that of several invertebrate groups, and supports the proposal of dividing the world into three main regions, Austral, Holotropical and Holarctic.