High diversity of small insectivorous mammals on Qinghai–Tibet Plateau and first description of karyotype for four endemics of China

Abstract

Among seven species of the order Eulipotyphla (from southern Gansu and northern Sichuan Provinces, Central China) studied cytogenetically, karyotypes of one talpid species, Uropsilus aff. soricipes (2n = 36, NFa = 54), and three soricid species, Chodsigoa hypsibia (2n = 65, NFa = 66), Sorex cansulus (2n = 42, NFa = 64) and Sorex thibetanus (2n = 42, NFa = 60), are described cytogenetically for the first time. All four species are endemic to China with distribution ranges restricted to the Qinghai–Tibet Plateau and adjacent mountain ranges. The Ch. hypsibia karyotype consists of mostly acrocentric autosomes and one metacentric pair of autosomes; besides, a B chromosome was identified. No polymorphism was detected among karyotypes of other species, including shrews Sorex bedfordiae (2n = 26, NFa = 44), Anourosorex squamipes (2n = 48, NFa = 92) and Crocidura suaveolens (2n = 40, NFa = 44). The Chinese shrew mole U. aff. soricipes and three shrew species (S. bedfordiae, Ch. hypsibia and A. squamipes) represent autochthonous fauna of Central/Western China, whereas S. thibetanus, S. cansulus and C. suaveolens belong to phylogenetic groups occurring mostly to the north and west from China; therefore, they should be considered relatively recent colonisers. Thus, considering the relationships of the species within phylogenetic groups, our results on karyotypes are in good agreement with molecular genetic data.

Supernumerary chromosomes contribute to karyotypic diversity within cryptic species of the subgenus Stenocranius (Cricetidae, Rodentia): comparative analyses of chromosomes and synaptonemal complexes

“…A review by Vujošević et al (2018) showed that the number of mammalian species with additional chromosomes is 85 (~ 1.9% of the karyotypically studied ones), and at least 60 of them are rodents, mostly from the superfamily Muroidea (Trifonov et al, 2010;Graphodatsky et al, 2011). In recent years, several new mammalian species -bats and insectivoreswere added into the category of B-carriers (Pavlova et al, 2021;Volleth et al, 2022;Rajičić et al, 2022).…”