COMPARISON OF ISOZYMIC AND MUSCLE PROTEIN IN 3 TAXA OF LEUCISCUS FROMNORTHERN ITALY

A biochemical-generic analysis was carried out on five samples of thre e species of Leuciscus, to verify the genetic divergence between Padan ian L. cephalus and L. souffia and to unravel the taxonomic status of a Leuciscus population preliminarly reported as Leuciscus sp., collect ed from the Adriatic drainage basins and morphologically related to L. lucumonis, a recently described taxon of the Tyrrhenian basins. Both isozymic data on 25 loci and total protein analyses identified Leucisc us sp, as L. lucumonis and showed the high genetic divergence and poly morphism of L. souffia with respect to L. cephalus and L. lucumonis. T his study confirms that L. lucumonis is a valid species that inhabits also Adriatic drainage basins and provides conclusive evidence that it is not originated by hybridization. In addition, genetic data fully s upport the hypothesis of a sharp divergence of L. souffia from congene ric taxa.