Abstract: During a investigation of Chiroptera diversity in Guangxi Zhuang Autonomous Region, seven Myotis bats (3 males and 4 females) were captured from May to June, 2023 in Tuoqi water conservancy tunnel, Youliaogu water conservancy tunnel, and G80 culvert in Tianyang District, and in Lilangtun tunnel in Leye County, all in Baise City, Guangxi Zhuang Autonomous Region. The species of the aforementioned specimens were identified using a combination of traditional morphological methods and molecular phylogenetic analysis. Among the captured specimens, four bats were small to medium size, with forearm lengths of 33. 7 - 37. 4 mm. The dorsal hairs are dark brown to black, with light gray on the abdominal hair tips near the tail, and the wings are a uniform dark brown. The skull is long and narrow, with a robust snout, relatively flat skull roof, and delicate cranial bones, with a noticeable slope at the frontal bone. These morphological characteristics and measurements are consistent with Myotis horsfieldii. The other three bats were medium-sized, with forearm length of 45. 2 - 45. 5 mm. The dorsal hairs are long and dark brown, with light yellow-brown tips on the abdominal hairs, and the wings are of a single color and attach at the base of the first toe. The skull is massive with a broad and short rostrum; the cranial profile is flattened. Zygomata are strong, and the sagittal and lambdoid crests are well pronounced. The morphological characteristics and measurements are consistent with those of Myotis indochinensis. Phylogenetic analysis based on the Cyt b gene also supported the above morphological identification results. This report represents a new distribution record of M. horsfieldii and M. indochinensis in Guangxi Zhuang Autonomous Region. The specimens are kept in the Institute of Zoology, Guangdong Academy of Sciences.

Key words: Chiroptera(Bat), Myotis horsfieldii, Myotis indochinensis, Guangxi Zhuang Autonomous Region, New record

关键词: 翼手目(蝙蝠), 霍氏鼠耳蝠, 印支鼠耳蝠, 广西壮族自治区, 新纪录