关键词: 明亮熊蜂复合种, 隐存种, DNA条形码, 遗传多样性, 系统进化, 分布格局

Abstract: 【Aim】 To explore the species composition and distribution characteristics of the bumblebee Bombus lucorum complex in China. 【Methods】 DNA (COI) barcodes were used to identify larger new samples of B. lucorum complex from China and then the distribution patterns of these species were plotted using these samples. 【Results】 B. lucorum complex in China includes four cryptic species, i. e., B. terrestris, B. cryptarum, B. lucorum and B. longipennis. From a total of 160 COI barcode sequences from the four species, 36 unique haplotypes were identified, with the highest diversity occurring within B. longipennis (14 haplotypes) and the lowest within B. terrestris (3 haplotypes). The longest genetic distance (0.077) was found between B. terrestris and B. lucorum, and the shortest (0.034) was found between B. lucorum and B. longipennis. Phylogenetic analysis of Bayesian and Maximum-likelihood methods showed that the divergence of the four species occurred in the order of B. terrestris, B. longipennis, B. lucorum, and B. cryptarum. Distribution patterns differed among the four species. The mean elevation of the four species ranks from high to low in the order of B. longipennis, B. cryptarum, B. lucorum, and B. terrestris. B. longipennis was found only at high elevation in the eastern and the southern Qinghai-Tibetan plateau, while B. terrestris was found only at low elevation in northwestern Xinjiang. 【Conclusion】 This study clarifies the species composition and distribution patterns of the bumblebee B. lucorum complex in China, which will be useful for further studies on resource conservation of these valuable bumblebee taxa and their use in agricultural pollination.

Key words: Bombus lucorum complex, cryptic species, DNA barcoding, genetic diversity, phylogenetic relationship, distribution pattern