Experimentally induced pigment changes in small African 'Barbus' (Teleostei : Cyprinidae): Synonymy of 'Barbus' amphigramma and 'Barbus' taitensis with 'Barbus' paludinosus

Pigmentation in fishes is known to be variable both among individuals of a species and within individuals over time. Use of pigment characters for tax onomic diagnoses must, therefore, be carefully considered. I present experi mental evidence showing that pigment characters previously considered diagn ostic for three small African 'Barbus' species may differ between living an d preserved specimens and that lasting changes in these characters can be i nduced experimentally by placing fishes in a different, less turbid environ ment. Lateral line pigmentation and presence of a spot on the caudal pedunc le showed significant changes that resulted in different species identifica tions before and after the experiment. These pigment patterns are thereby s hown to be labile, nontrenchant characters having little or no diagnostic u tility. 'Barbus' amphigramma Boulenger, 1903, and 'Barbus' taitensis Gunthe r, 1894, are thus shown to he junior synonyms of 'Barbus' paludinosus Peter s, 1852.