Inland free-living nematodes in China: A historical review of taxonomic studies with descriptions of Aphanonchus orientalis sp nov (Chromadorida : Leptolaimidae) and Daptonema limnobia sp nov (Monhysterida : Xyalidae)

The study of inland free-living nematodes is relatively imperfect in China, only seventeen papers were previously published. Since the early researche s in 20-30s, few works have been accomplished until 80s. Altogether 171 tax a were formerly recorded, among which, over eighty species have been re-com bined. A checklist of the former records with notes on their distribution i s presented in this paper. Recently, the function of free-living nematodes has received much attention from Chinese zoologists. Hence, the present authors carried out their stud ies with emphasis on taxonomy of inland nematodes. During the survey of fre shwater lakes, two species are found to be nem to science. Aphanonchus orie ntalis sp. nov. is characterized by having sclerotized vagina, the presence of 10-11 tubular supplements and 42-62 alveoli supplements in males, but n o alveoli in females. Daptonema limnobia sp, nov. is distinguished from oth er species of the genus in the presence of larger and more anteriorly locat ed amphids, shorter bifurcated spicules, smaller apophysis of gubernaculum, shorter terminal setae, and postvulval uterine sac in females.