A new species and a new subspecies of Amynthas Kinberg, 1867 earthworms (Oligochaeta, Megascolecidae) from northwestern China with data from the mitochondrial genome

Two new taxa of the earthworm genus Amynthas Kinberg, 1867 are described from northwestern China: Amynthas longnanensis sp. nov. from Longnan, Gansu Province, and Amynthas pectiniferus guanzhongensis ssp. nov. from Weinan, Shaanxi Province. Both belong to the A. sieboldi group, characterized by three pairs of spermathecal pores in 6 / 7–8 / 9. Species delimitation based on COI barcoding (ASAP and GMYC) and phylogenetic analysis using mitogenomic protein-coding genes (PCGs) support their recognition as distinct lineages.

The mitogenomic phylogeny reveals that the A. sieboldi group as currently defined is not monophyletic. The new findings fill a distributional gap of Amynthas in northwestern China and provide new morphological and molecular data for understanding earthworm diversity.