Phylogenetic relationships between 21 species of three tilapiine genera Tilapia, Sarotherodon and Oreochromis using allozyme data

With the aim of detecting speciation events in Tilapia sensu lato, 24 enzyme loci were studied in eleven species of the genus Tilapia, four species fo the genus Sarotherodon, five species fo the genus Oreochromis and five other species belonging to similar genera (Pelmatochromis, Chilochromis, Tylochromis, Hemichromis and Chromidotilapia). The phylogenetic trees obtained show a clustering of species (except for Sarotherodon melanotheron) according to their genera, i.e. Tilapia, Sarotherodon or Orechromis, which confirms the systematics adopted by Trewavas. The phylogenetic trees obtained by rooting with species belonging to similar genera confirm the hypothesis that mouthbrooders (Sarotherodon and Oreochromis) have a single origin, i.e. egg layers (Tilapia), and negate the hypothesis of multiple speciation of Peters and Berns. Copyright © 1995, Wiley Blackwell. All rights reserved