Africa Museum, Cichlid Research Unit, Leuvensesteenweg 13, B-3080 Tervuren, Belgium

The cichlid diversity of Lake Malawi/Nyasa/Niassa: identification, distribution and taxonomy

During the SADC/GEF Lake Malawi/Nyasa/Niassa Biodiversity Conservation Project, the systematics of the endemic cichlids of Lake Malawi was intensively studied. A lake-wide sampling program was set up to study and sample the cichlid diversity. Based on these samples, various taxonomic revisions were undertaken, mainly on the economically more important non-mbuna. This research was continued during the recent EU sponsored Malawi demersal fish project.

Revisions have been made of Alticorpus, Ctenopharynx, Nimbochromis, the shallow-water Lethrinops, the deep-bodied spotted Utaka, the deep-water Placidochromis, the Lethrinops longipinnis complex and the Copadichromis virginalis complex. Some of the striking results include the discovery of a sub-flock of 47, mostly undescribed deep-water Placidochromis species, and the possible presence of polymorphism and polychromatism in C. nitidus. With the discovery of many new species, it became clear that the definitions of certain genera (Copadichromis/Otopharynx, Alticorpus/Aulonocara, Lethrinops/Placidochromis, Sciaenochromis/Mylochromis, etc.) are ambiguous and in need of revision.

Geographic variation was recorded in various species and an effort has been done to analyse the morphometric data of some in more detail.

Furthermore, a review was made of the distribution of the cichlids on a lake-wide scale to look for possible biodiversity hotspots. Also for the first time, the distribution database was analysed in an ichthyogeographical context. An effort is currently done to produce guidelines to the identification of less well-studied taxa.