Phylogenetic analysis of Mediterranean Mugilids by allozymes and 16S mt-rRNA genes investigation: are the Mediterranean species of Liza monophyletic?

The family Mugilidae (Pisces, Mugiliformes) includes species which are present in all tropical and temperate regions. Six species, Chelon labrosus, Mugil cephalus, Liza aurata, L. ramada, L. saliens, Oedalechilus labeo, are commonly found in the Mediterranean. These species have been widely studied through morphological, biochemical, and molecular markers. However, their phylogenetic relationships, and therefore the assumed monophyly of Liza species, still remain unclear: To further investigate this topic, gene-enzyme systems and sequences of the partial 16S rRNA mitochondrial gene were analyzed in Italian samples of all six Mediterranean species. The phylogenetic reconstructions indicated M. cephalus as being the most divergent species and the existence of a main cluster including all the Mediterranean species of Liza and C. labrosus. The parametric bootstrap approach adopted to test alternative phylogenetic hypotheses indicated that the Mediterranean species of Liza do not form a monophyletic group exclusive of Chelon.