The reds and the yellows: a review of Asian Chrysopteron Jentink, 1910 (Chiroptera: Vespertilionidae: Myotis)

Chrysopteron Jentink, 1910 is 1 of the 7 subgenera of Myotis Kaup, 1829 recognized by Tate that traditionally comprises Asian and African species characterized by conspicuously parti-colored wing membranes. Definition of Myotis subgenera has long challenged taxonomists and prior to the present study the systematic status of numerous forms within Chrysopteron remained unclear. Following examination of material (including available type specimens) in 21 European, North American, and Asian collections, and using morphological (external, cranial, and dental characters) and genetic data, we evaluate the validity of the Chrysopteron subgenus, revise the taxonomy of the named Asian forms, and review their distinguishing characters, distribution, and taxonomic history. We argue that Chrysopteron is an available name for a monophyletic Ethiopian clade recovered with high support in our analyses, which comprises species characterized by striking reddish or yellowish dorsal fur that strongly differentiates them from congeners. We also determine that M. formosus sensu lato contains several morphologically distinct forms, some of which occur in sympatry and some in widely separated localities. A morphological key is provided for all Asian species of Chrysopteron revealed by our study: M. bartelsi Jentink, 1910 (Java and Bali), M. formosus (Hodgson, 1835) (Afghanistan, India, Nepal, China, Taiwan, and Vietnam), M. hermani Thomas, 1923 (Sumatra, Thailand, and Malaysia), M. rufoniger (Tomes, 1858) (Korea, Japan, China, Taiwan, Laos, and Vietnam), M. rufopictus (Waterhouse, 1845) (Philippines), and M. weberi (Jentink, 1890) (Sulawesi).