Theristus coralis sp. n. and Thalassomonhystera gracilima sp. n. (Nematoda, Monhysterida) from coral reef off the coast of Vietnam

Abstract

Two new nematode species of the order Monhysyterida from coral reef off the coast of Vietnam are described and illustrated. Theristus coralis sp. n. is morphologically similar to Th. macroflevensis Gerlach, 1954 and Th. metaflevensis Gerlach, 1955 and differs from both species by presence of cardial glands and posterior sack of uterus, longer pharynx, shorter gubernaculum and closer to anterior body end located vulva. Thalassomonhystera gracilina sp. n. resembles Th. tasmaniensis (Allgen, 1927) but has longer and thinner body, longer tail in females and longer and different structures of spicules and a different structure of stoma.

Keywords

• free-living marine nematodes
• morphology
• new species