Abstract:Mt. Ailao, Mt. Wuliang and Mt. Cang are the key areas of biodiversity in Yunnan Province (Fig. 1), China. In order to reveal the taxonomy and phylogeny of earthworms from these areas, specimens were collected by digging and hand-sorting methods (Fan et al. 2012) in 2010, 2011 and 2016. Both morphological and phylogenetic methods were used to identify species. We analyzed both composition and p-distance based on either mitochondrial COⅠ, COⅡ, 12S rRNA, 16S rRNA, ND1 sequences or their combined genes. Phylogenetic trees and ancestral distribution area were also reconstructed with the combined genes. As results, a total of 3 families, 8 genera and 27 species of earthworm species were classified, including 21 species of Megascolecidae, 4 species of Lumbricidae, and 2 species of Moniligastridae (Table 1). Three new species were identified, and they were Amynthas wuliangmontis sp. nov., Amynthas jingdongensis sp. nov. and Amynthas lacustris sp. nov (Fig. 2). The mitochondrial COⅠ, COⅡ, 12S rRNA, 16S rRNA, and ND1 genes were sequenced, and the average inter-species p-distance of combined sequences was determined to be 19.6% ± 0.5% (Table 2), while the average intra-species p-distance was 0﹣2.7% (Table 3). Both Maximum Likehood tree and Bayesian Inference (BI) tree showed the same phylogenetic relationship of these specimens (Fig. 3). We classified the BI tree into 7 clusters. Cluster 1 was constructed of all 4 Lumbricidae species. However, Clusters 2﹣7 were constructed of all Megascolecidae specimens. According to Cluster 7, it was verified that Amynthas and Metaphire were in a mixed group. Moreover, we suggested that the diffusion direction of Megascolecidae was from south to north according to the reconstruction of ancestral distribution area (Fig. 4), hence species may spread from Mt. Wuliang & Mt. Ailao to Mt. Cang. This is the first attempt for taxonomy and phylogeny analysis of earthworms in extension of Yunling Mountains. Our results show the biodiversity as well as the close phylogenetic relationship of earthworm species in this region, which will be valuable for further researching earthworms in southeast China.
