The 11 genera of Nearctic Braconini are keyed: two of them, Myosoma Brullé with a wide pantropical range and Alienoclypeus Shenefelt, new genus, are found chiefly in the Chihuahuan desert and shrub fauna of northern Mexico and the southwestern U.S.A. and are recorded as Nearctic for the first time. Four new species are described in Myosoma: eumystax, impexum, longius, and durango. R. D. Shenefelt describes a new genus and species, Alienoclypeus insolitus. The genus Atanycolimorpha Viereck, 1913 is synonymized with Ipobracon Thomson, 1892. The genus Coeloides is revised for the Nearctic Region; 12 species are described and illustrated. Five of these are new: mexicanus, durangensis, sympitys, tsugatorus, and sonora. One species, C. rossicus (Kokujev), is Holarctic, a new subspecies, betulae, is described from Canada. The following are new synonyms: C. rufovariegatus (Provancher) = (dendroctoni Cushman), C. vancouverensis (Dalla Torre) = (brunneri Viereck), C. crocator (Kirby) = (promontorii Dalla Torre).