Morphological analysis of the pharyngeal jaws in two populations of Lebiasfasciata Valenciennes, 1821 (Teleostei : Cyprinodontidae)

The study of the pharyngeal jaws in two geographically isolated Italian pop ulations of Lebias fasciata indicated the presence of two phenotypes: the A driatic phenotype with a large ceratobranchial V and upper and lower pharyn geal jaws bearing few large teeth and the Sicilian phenotype with a smaller ceratobranchial V and pharyngeal jaws with smaller and more numerous teeth . The morphological variations of pharyngeal jaws should be interpreted as a result of the geographical isolation of these two populations. (C) 1999 W iley-Liss, Inc.