Description of Paravulvus zhongshanensis sp. nov. (Dorylaimida: Nygolaimidae) from Nanjing, China.

Paravulvus zhongshanensis sp. nov., isolated from soil in a location at Jiangsu Province, China, is described and illustrated based on morphological, morphometric and molecular characterizations. The new species is characterized by its body 1.17-1.53 mm long, lip region offset by marked constriction and 12.1-13.8 μm broad, mural tooth deltoid and 9.6-11.7 μm long, neck 278-360 μm long, pharyngeal expansion 164-208 μm long or occupying more than one-half (54-62%) of total neck length, uterus 32.5-35.3 μm long or 1.0-1.1 times the corresponding body diameter, V = 47.8-53.4, paravulvae absent, female tail subcylindrical conoid (30.5-39.5 μm, c = 36.0-45.5, c' = 1.7-2.2) with widely rounded end, and male unknown. The new species was compared with six known species of the genus including Paravulvus acuticaudatus, Paravulvus confusus, Paravulvus hartingii, Paravulvus iranicus, Paravulvus loofi and Paravulvus microdontus mainly by similarities in having conical tail and c' value larger than 1.3. The rRNA and mitochondrial cytochrome oxidase subunit 1 genes of the new species were obtained and were used for reconstructing the phylogenetic relationships of the new species.