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

The study of the pharyngeal jaws in two geographically isolated Italian populations of Lebias fasciata indicated the presence of two phenotypes: the Adriatic phenotype with a large ceratobranchial V and upper and lower pharyngeal 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. J. Morphol. 241:107–114, 1999. © 1999 Wiley‐Liss, Inc.