First karyotype description of the Indochinese shrew Crocidura indochinensis Robinson et Kloss, 1922 (Mammalia, Eulipotyphla, Soricidae) from Yunnan, China.

The small-sized Crocidura horsfieldii (Tomes, 1856) species complex, comprising C. watasei (Kuroda, 1924), C. tadae (Tokuda et Kano, 1936), C. kurodai (Jameson et Jones, 1977), C. wuchihensis (Wang, 1966), and C. indochinensis (Robinson et Kloss, 1922), has long been the subject of taxonomic confusion in the literature. Here, we report for the first time the karyotype of female C. indochinensis from Yongde Snow Mountain, based on conventional Giemsa staining and the GTG-banding technique. C. indochinensis has 2n = 38 and FN = 56. The autosomes consist of four metacentric or submetacentric pairs, four subtelocentric pairs, and ten acrocentric pairs, whereas the X chromosome is a medium-sized submetacentric. Our results demonstrate that the karyotype of C. indochinensis differs markedly in 2n and FN from those of C. horsfieldii, C. watasei, C. tadae and C. kurodai, providing further evidence for the distinct species status of C. indochinensis within this complex. Furthermore, comparative analysis of the G-banded chromosomes of C. indochinensis and C. dsinezumi revealed a high degree of karyotypic homology, with their karyotypes differing primarily by a single fusion/fission event and a centromeric shift or a pericentric inversion, thereby enhancing our understanding of karyotype evolution within the genus Crocidura Wagler, 1832.