Morphological Comparisons Of Crocidura Attenuata Species Complex In Chinese Mainland

The Asian Gray Shrew Crocidura attenuata(Milne-Edwards,1872)and the Taiwanese Gray Shrew C.tanakae(Kuroda,1938)are species of the same genus with highly similar morphological characteristics.In recent years,C.tanakae was reported to be widely distributed in mainland of China,and is sympatry with C.attenuata in some areas.Prior studies have confirmed that the "C.attenuata" in the mainland of China is a species complex including three species.Because their extremely similar morphological characteristics and measurements,C.tanakae had been wrongly identified as C.attenuata in the mainland of China.In recent years,geometric morphometrics have been widely used to many aspects such as species classification,identification,intraspecies and interspecies morphological differentiation.For conforming suitability of morphological indices to the classification and species identification,we compared morphological indices among the species of C.attenuata species complex including multivariable analyses(PCA,cluster analysis,and discriminant analysis),and especially conducted geometric morphology analyses using skulls of the three species.Our results showed that:1.neither classical morphological analyses(including multivariable methods)nor geometric morphological procedures can classify C.attenuata and C.tanakae,however,geometric analyses can classify the cryptic species from C.attenuata and C.tanakae;2.morphological indices are almost unable to distinguish the species among C.attenuata species complex,even discriminant method had a relatively high correct ratio(90.05%)when using dorsal view of skull;3.the cryptic species is evendently smaller then C.attenuata and C.tanakae in body size,however,morphological indices are considered to be not suitable for species indentification in field because we could not conduct age estimate of the species.