Karyotypic evolution in family Hipposideridae (Chiroptera, Mammalia) revealed by comparative chromosome painting, G- and C-banding.

Comparing to its sister-family (Rhinolophidae), Hipposideridae was less studied by cytogenetic approaches. Only a few high-resolution G-banded karyotypes have been reported so far, and most of the conclusions on the karyotypic evolution in Hipposideridae were based on conventional Giemsa-staining. In this study, we applied comparative chromosome painting, a method of choice for genome-wide comparison at the molecular level, and G- and C-banding to establish comparative map between five hipposiderid species from China, using a whole set of chromosome-specific painting probes from one of them (Aselliscus stoliczkanus). G-band and C-band comparisons between homologous segments defined by chromosome painting revealed that Robertsonian translocations, paracentric inversions and heterochromatin addition could be the main mechanism of chromosome evolution in Hipposideridae. Comparative analysis of the conserved chromosomal segments among five hipposiderid species and outgroup species suggests that bi-armed chromosomes should be included into the ancestral karyotype of Hipposideridae, which was previously believed to be exclusively composed of acrocentric chromosomes.

[New record of a bat species from China, Megaderma spasma (Linnaeus, 1758)].

One male bat was collected in a cave in Cuibi Hill (N: 21 degree 53', E: 101 degree 18', H: 683 m a.s.l.), Menglun Town, Mengla County, Yunnan Province, on November 26, 2006. This bat is of medium body size, with 60.7 mm forearm and 21.4 g body mass. Its ears are large ovals and joined medially to the forehead at about 15% of the height of inner margin. The tragus of each ear is slender and distinctly bifid. The noseleaf is simple, and the posterior noseleaf is oval with obtuse tip and convex sides, a significant longitudinal ridge laying middle, which connects to intermediate noseleaf at the base. Intermediate noseleaf presents triangle with a W-shaped tip. Frontal noseleaf is horseshoe shape and attached directly to the muzzle. The tail is absent, and the second finger of each wing has only one phalanx. There are no upper incisors, Pm3 and Pm3. The upper canine has an anterior and a large posterior basal cusps. This bat is identified as lesser false vampire, Megaderma spasma, which is a new record of China. Its external and craniodental measurements were presented and compared with those of M. lyra. The specimen is preserved in Guangdong Entomological Institute.

Pleistocene climatic cycling drives intra-specific diversification in the intermediate horseshoe bat (Rhinolophus affinis) in Southern China.

The repeated formation and loss of land-bridges during the Pleistocene have had lasting impacts on population genetic structure. In the tropics, where island populations persisted through multiple glacial cycles, alternating periods of isolation and contact are expected to have driven population and taxonomic divergence. Here, we combine mitochondrial and nuclear sequence data with microsatellites to dissect the impact of Pleistocene climate change on intra-specific diversification in the horseshoe bat Rhinolophus affinis. This taxon shows considerable morphological and acoustic variation: two parapatric subspecies (himalayanus and macrurus) occur on mainland China and a third (hainanus) on Hainan Island. Our phylogeographic reconstruction and coalescent analyses suggest the island subspecies formed from an ancestral population of himalayanus via two colonization events c. 800,000 years before present. R. a. hainanus then recolonized the mainland, forming macrurus and thus a secondary contact zone with himalayanus. Finally, macrurus recolonized Hainan following the LGM. We found that all three biological events corresponded to known periods of land-bridge formation. Evidence of introgression was detected between macrurus and both its sister taxa, with geographical proximity rather than length of separation appearing to be the biggest determinant of subsequent genetic exchange. Our study highlights the important role of climate-mediated sea level changes have had in shaping current processes and patterns of population structure and taxonomic diversification.