Morphological and molecular characteristics of Bastiania sinensis sp. n., Tripyla aquatica Brzeski & Winiszewska-Slipinska, 1993 and T. setifera Butschli, 1873 (Nematoda: Triplonchida) from Shanxi Province, North China

This paper describes a new species of Bastiania, presents a new record and redescribes a known species of Tripyla. These nematodes are all in the order Triplonchida and were collected from Shanxi Province, North China. Bastiania sinensis sp. is characterised by having the female with a relatively slender body 1049-1295 mu m long, dorsally arcuate after heat relaxation, with outer labial setae and cephalic setae in a single circle, an oval amphid, 7-8 laterodorsal cervical setae scattered in the pharyngeal region, orthometamenes and pseudocoelomocytes present, tail conoid with a mucron 1-2 mu m long, two pairs of caudal setae present, a 58.1-75.5, b = 4.0-4.6, c = 12.7-19.7, c' = 4.1-7.8 and V = 61.1-67.7. Males were not found. Tripyla aquatica is recorded for the first time from China, and is redescribed. Tripyla setifera has been reported from China but without a detailed description - now provided. In addition, phylogenetic relationships among the species were analysed using data from the near full length small subunit (SSU) and D2-D3 segments of large subunit (LSU) of rRNA genes. Bastiania sinensis sp. n. is monophyletic with the Bastiania sequences available in GenBank, but is on an independent branch supporting its status as a separate species; T. aquatica and T. setifera are monophyletically clustered with known Tripyla species and grouped together with sequences from their respective species.