Discrimination of the sympatric species of water shrews Neomys fodiens and N. milleri (Soricomorpha, Soricidae)
Abstrakt
The water shrew species Neomys fodiens and Neomys milleri are morphologically similar and, based on phenotype, it is difficult to distinguish them. Mandibles of both species were studied by means of classic as well as geometric morphometrics.
We compared a priori identified mandibles of water shrews captured in two areas where the species ranges partially or entirely overlap, i.e., in Germany and in the south-eastern part of the Balkan Peninsula. Discrimination of the two species by linear measurements was successful in Germany but not in the Balkans.
Discriminant analysis revealed clear differences in the shape of the mandible between the species in both regions. Comparison of allopatric and sympatric populations of both species showed that species are smaller and more similar in shape where they occur in sympatry.
Our results suggest that geometric morphometrics can be successfully used for species determination, especially in regions where determination by size is not possible.