Molecular Taxonomy of European Plethodontid Salamanders (Genus Hydromantes)

Genetic variation of 33 enzyme loci was analysed electrophoretically in 32 populations of the plethodontid genus Hydromantes from southern France, northern and central Italy, and Sardinia. Eight taxa were recognized, included in three groups: from the mainland, eastern Sardinia, and south-western Sardinia, respectively. In the mainland area, two semispecies were detected: H. italicus and H. ambrosii (sensu stricto), as well as a third species: H. strinatii (combinatio nova), previously included within H. ambrosii. Eastern Sardinian populations correspond genetically to three species: H. flavus, H. supramontis, and H. imperialis. In south-western Sardinia, two genetically differentiated but morphologically very similar groups were found within H. genei, whose specific status remains doubtful. The distinctness of a number of subspecific taxa (H. italicus gormani, H. i. ligusticus, H. i. argentatus, H. i. bonzanoi, H. genei funereus), is not supported by genetic evidence. Data from two contact zones in Italy indicate that taxa showing comparable levels of genetic differentiation (i.e., H. italicus-H. ambrosii s. s. and H. ambrosii s. s.-H. strinatii, both pairs with Nei's D about 0.4) have not reached the same level of reproductive isolation. On the basis of available data, attempts are made: (1) to interpret the present pattern of geographic distribution of European Hydromantes studied; (2) to explain their genetic relationships.