Although the cuticle and anterior end of marine and freshwater nematodes are usually provided of setae and other appendices, terrestrial nematodes are usually devoid of such structures to facilitate movement between soil particles. However, the anterior end of Discolaimus is not rounded off. In Discolaimus, the anterior end is provided of a disc-shaped structure which is used to adhere to other soil organisms, including nematodes. Subsequently the nematode uses its spear to pierce the cuticle of its prey and to suck the content of the body. It is a remarkable nematode which is easily recognized; in the Netherlands it is quite common in dune sand.
More pictures of Discolaimus major:
(Click on the pictures for an enlargement, © Wageningen University & Research, Laboratory of Nematology/Pictures: Hanny van Megen)