The Sorex araneus group in the northern Iberian System (Spain): a contact zone between S-coronatus and S-granarius?

Available information on the distribution of the European species of the So rex araneus group in the Iberian Peninsula suggests that the Iberian System (north-central Spain) might be a sympatric area between S. coronatus Mille t, 1828 and S. granarius Miller, 1910. With the aim to assess this hypothes is, multivariate analyses based on 16 skull and mandible parameters were ca rried out on 78 shrews from the Iberian System. A preliminary specific dete rmination was performed on 57 specimens using a discriminant function estab lished in a previous study. Two further discriminant functions based on sku ll and mandible variables respectively were constructed from the sample ana lysed and both provided an identical classification of the specimens, altho ugh slightly different from that of the preliminary determination. In order to summarize the morphometric interspecific relationships a principal comp onents analysis was performed. Results obtained confirm the presence of S. coronatus and strongly suggest that of S. granarius and of a contact zone b etween both species in the Iberian System. In this area both species share the same general habitats, occupying oro- and supramediterranean bioclimati c levels. Taking into account the distributional pattern reported for S. ar aneus and S. coronatus in sympatric areas, and considering the convergence in size observed between S. granarius and S. coronatus in the Iberian Syste m, we suggest that in this contact zone both species might have a parapatri c distribution, due most probably to microhabitat segregation.