Free-living nematodes from mangrove forest in the Yn River estuary (Vietnam)

Fifty species of free-living nematodes have been found in the Yn River estuary (northern Vietnam), ten of which are newly described species. The dominant species are Valvaelaimoides macroamphida Gagarin, 2016; V. minor Gagarin, 2016; Micromicron cephalatum Cobb, 1920; and Sphaerotheristus nothus Gagarin, Nguyen Vu Thanh, 2008. A list of the nematodes species, an illustrated description of the new species Theristus consobrinus sp. n., the main morphometric parameters of 13 valid species of the species group flevensis of the genus Theristus, and a pictorial key for determining males of this species group are provided.