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.