Distribution patterns and biogeography of non-tropical southern african freshwater fishes

The nature and distribution of the southern African freshwater fish fauna is reviewed in broad terms. Two basic faunal groups are identified, a larger and more widespread tropical fauna and an endemic temperate fauna. Distribution patterns of temperate taxa are examined and categorised as either ‘Cape’ or ‘karroid’. Certain distribution patterns, particularly of Cape species, are uninformative as the phyletic relationships of the taxa are not known. By way of exception, a cladogram of the redfin minnows, which form a prominent and monophyletic Cape lineage, is used to explain their distribution. A distinctive common pattern of distribution of karroid taxa is found. The pattern is explained on the basis of a broad model of hydrographic evolution. The model integrates the information provided by the phylogenetic relationship and the distribution of the redfin minnow with that of karroid species.