The North American species of Brachylomia Hampson, 1906 are revised and four new species (B. cascadia sp. nov., B. obscurifascia sp. nov., B. pallida sp. nov., and B. sierra sp. nov.) are described. The monotypic genus Lomilysis Franclemont, 1937 is synonymized with Brachylomia. Epunda onychina Guenée, 1852, which is currently placed in Brachylomia, is reclassified as a senior synonym of Egira alternans (Walker, ), but Epunda onychina, not being associated with any known species in more than 150 years, is treated as a nomen oblitum, so Egira alternans is a nomen protectum under provisions of Article 23.9.2 of the International Code of Zoological Nomenclature. Adults and genitalia of Nearctic species of Brachylomia are figured.