Two new genera of Drilonematoidea from earthworms deposited in the collection of the Smithsonian Institution's Natural History Museum are described. Acanthungella africana gen. n., sp. n. (Ungellidae) was found parasitic in the coelomic cavity of Millsonia nigra Beddard, 1894 and Araguanema venezuelae gen. n., sp. n. (Drilonematidae) was found in the coelomic cavity of Rhinodrilus sp. Acanthungella africana gen. n., sp. n. is closely related to Ungella Cobb, 1928, but distinguished from it and the rest of the ungellid genera by having a series of numerous sublateral sensilla through the length of the body. Araguanema venezuelae gen. n., sp. n. is similar to two other monotypic drilonematid genera, namely Diceloides Timm, 1967 and Mbanema Spiridonov, 1992, in having vesicular sensory organs. Araguanema gen. n. can be distinguished from Diceloides by the number and position of lateral fimbriate and vesicular sensory organs; the nerve ring located around the isthmus of the pharynx vs at the pharyngo-intestinal junction; a single ovum in the uterus vs more than 100 ova; presence vs absence of an excretory duct; long fibres protruding from the anal aperture vs the absence of such fibres; and by the absence vs presence of a spermatheca. Araguanema gen. n. differs from Mbanema in having a cylindrical vs a clavate pharynx, and by the presence of anterior and caudal fimbriate organs vs caudal only.