Phylogenetic relationships between seven species of the catfish species flock from
Lake Malawi (genus Bathyclarias) and other Clariid catfish have been investigated
using cytochrome b partial sequences. Here we demonstrate that this species flock
originated from a widespread, generalist species, Clarias gariepinus, still
occurring in the lake. Bathyclarias species and their ancestor C. gariepinus
form a simple model that can be used to understand the mechanisms of adaptation and rapid
speciation in African Great lakes.