The family Scelionidae is thought to be a paraphyletic assemblage within the Platygastroidea. The tribes Nixoniini and Sparasionini are generally thought to be the most basal and plesiomorphic components of the family. The Nixoniini are monobasic, and the Sparasionini (sensu Masner) consist of three genera: Archaeoteleia Masner, Sparasion Latreille, and Sceliomorpha Ashmead. We review the taxonomy and distribution of Nixonia Masner and Sceliomorpha. Nixonia is known from only two described species from southern Africa. In fact, the genus contains 12 species and is widely distributed in Africa, Sri Lanka, and southeast Asia. Sceliomorpha is a Neotropical group with only eight described species. Our revisionary studies now document over 40 species found from Argentina and Paraguay north to the southwestern United States. The relationships of Nixoniini and Sparasionini with other scelionids and platygastrids are discussed.