中国产托京褐扁颅蝠分类地位的探讨

Study on Taxonomic Status of Tylonycteris tonkinensis from China

于2020年6月在福建省武夷山使用蝙蝠竖琴网采集到2只小型蝙蝠(1♂,1♀)。其外部形态、毛色及头骨特征与近期在越南、老挝被修订为新种的托京褐扁颅蝠(Tylonycteris tonkinensis)的形态特征(原名褐扁颅蝠T.robustula)相吻合。鉴于近年扁颅蝠属分类体系发生较大变动,为理清“褐扁颅蝠”与托京褐扁颅蝠在中国分布疑难,对来自国内8省的75号馆藏“褐扁颅蝠”标本进行分类厘定。其中依据COⅠ和Cyt b基因(21号样本)构建的分子系统发育树显示,上述标本与NCBI-nt数据库中越南和老挝产的托京褐扁颅蝠聚为高支持度的一支,支持中国区域仅分布托京褐扁颅蝠,无褐扁颅蝠分布,亦未见在越南南部分布的马来褐扁颅蝠(T.malayana)。武夷山标本为福建分布新纪录。故我国扁颅蝠属内现有3种,分别为:小扁颅蝠(T.pygmaea),仅分布云南南部;华南扁颅蝠(T.fulvida),分布台、港、粤、桂、黔、云;托京褐扁颅蝠,分布闽、赣、港、粤、琼、桂、黔、云、川。同时,种群遗传结构和历史动态结果分析表明,国内外托京褐扁颅蝠种群混杂,无明显的种群遗传结构,在更新世前后存在种群扩张历史。

Two small vespertilionid bats(1♂♂,1♀♀)were collected by harp traps in June 2020 in Wuyi Mountain,Fujian Province,China.Their external morphology,pelage coloration,and skull characteristics matched those of Tylonycteris tonkinensis(formerly identified as T.robustula in China),a new-found species from Vietnam and Laos after comparative phylogeographic analyses.Since recent changes in the taxonomy of Tylonycteris,we further conducted morphological and phylogenetic analyses including 75“Tylonycteris robustula”from eight provinces of China.Molecular phylogenetic inferences based on COⅠand Cyt b gene segments(21 samples included)confidently clustered all samples from China with T.tonkinensis from Vietnam and Laos rather than T.robustula or T.malayana that is found in South Vietnam.Such identification was supported by our morphological examinations and measurements.Our results confirm occurrences of T.tonkinensis in China rather than T.robustula.The discovery of T.tonkinensis from Wuyi Mountain represents a new chiropteran record in Fujian Province,China.Thus far,three Tylonycteris species are recorded in China,namely T.pygmaea,which is only found in type locale in Yunnan;T.fulvida,which is distributed in Taiwan,Hong Kong,Guangdong,Guangxi,Guizhou and Yunnan;T.tonkinensis,which presently distributed in Fujian,Jiangxi,Hong Kong,Guangdong,Hainan,Guangxi,Guizhou,Yunnan and Sichuan.Our phylogeographic analyses on T.tonkinensis reveal an intertwined relationship and a historical population expansion during the Pleistocene.