Three New Earthworm Species of the Genera Amynthas and Metaphire (Oligochaeta: Megascolecidae) From Leshan, China

Based on morphological and molecular evidence, three new earthworm species of the genera <i>Amynthas</i> Kinberg, 1867 and <i>Metaphire</i> Sims and Easton, 1972 from Leshan City of southwest China's Sichuan Province were identified in this study. They are named <i>Amynthas agenesis</i> sp. nov., <i>Metaphire jinhensis</i> sp. nov., and <i>M. ebianensis</i> sp. nov. All three new species have a large size (the dimensions of the adult body are more than 200 mm × 10 mm) and three pairs of spermathecal pores in 6/7-8/9. Although these three new species are morphologically somewhat similar to the other species in the same group, they are distinguishable in several morphological characteristics. <i>Metaphire jinhensis</i> sp. nov. has paired and bunchy ovaries that are attached to septa 12/13. <i>Metaphire ebianensis</i> sp. nov. has large and well-developed prostate glands, and each of its seminal vesicles has a dorsal lobe. <i>Amynthas agenesis</i> sp. nov. has accessory glands in spermathecae, prostate, and intestinal caeca regions. The maximum likelihood tree was constructed based on the mitochondrial cytochrome <i>c</i> oxidase subunit I gene, and it showed that the three new species are clustered on different branches. Besides, phylogenetic trees also suggested that the genera <i>Amynthas</i> and <i>Metaphire</i> did not evolve separately within their respective taxa and thus were not monophyletic. This study provides a detailed taxonomic characterization of three new species and helps to better understand the species diversity of earthworms, which is urgently needed to ensure the ecological stability of wild earthworms.