Karyotype of the Gansu mole (Scapanulus oweni): further evidence for karyotypic stability in talpid

摘要

Little is known about the ecology and evolution of the Gansu mole (Scapanulus oweni). The morphology of this monotypic genus (Talpidae, Eulipotyphla, Mammalia) indicates that it should fall into the tribe Scalopini. Although all the other scalopines are distributed in North America, S. oweni is endemic to Central and Southwest China. Previous studies have indicated that the chromosomes of talpid moles exhibit remarkable stability. However, the karyotype of S. oweni has not been determined. In this study, we report the karyotypes including G-banding and C-banding patterns of S. oweni. The diploid and fundamental autosomal numbers are 34 and 64, respectively, identical with six other talpid species and thus providing another line of evidence for chromosomal uniformity in this family. The models of karyotype stability are discussed, none of which adequately explains the chromosomal conservatism. We suggest that comprehensive approaches are needed to test in which degree that the chromosomal rearrangement, phylogeny, phylogeography and ecological adaptation have shaped the chromosomal evolution in this family.