Abstract
This paper describes the general morphology of nematodes of the Order Dorylaimida (superfamilies Belondiroidea, Nygolaimoidea and Tylencholaimoidea), including their cuticle, lateral chords, lip region, amphids, feeding apparatus, pharynx, pharyngo-intestinal junction, intestines, rectum, and female and male genital systems. It briefly discusses the diversity of freshwater Dorylaimida, and provides taxonomic details, illustrations and keys to its genera.