Abstract
The genus Parapenia Suzuki from China is revised, with 12 species recognized, including six new species: P. fuxisp. nov., P. nyuwasp. nov., P. pangusp. nov., P. ruihangisp. nov., P. wuchaoisp. nov., and P. zhengisp. nov. In addition, P. sausai Schimmel and P. villosa (Fleutiaux) are newly recorded from China, and P. jagemanni Schimmel syn. nov. is synonymized with P. yunnana Schimmel. Large plate-like sclerites in the bursa copulatrix are consistently present in Parapenia and show diagnostic value for generic delimitation. Comparative morphological studies, particularly of these sclerites, justify the establishment of three new genera distinct from Parapenia: (1) Parapenioidesgen. nov., including P. zidanisp. nov.; (2) Megapeniagen. nov., including M. cruciata (Bouwer) comb. nov., type species M. marginalis (Fleutiaux) comb. nov., and M. tianlongisp. nov.; and (3) Sinopeniagen. nov., including S. significata (Schimmel) comb. nov. A comparative diagnostic table of the four genera, together with a checklist and distribution maps, is provided. Identification keys to Chinese species of Parapenia and Megapenia are also included. This study clarifies the taxonomic complexity of Parapenia and emphasizes the overlooked significance of sclerotized structures in the bursa copulatrix for distinguishing genera within Dimini.