Three species in two genera are recognized for the family Biphyllidae in America, north of Mexico: Diplocoelus brunneus LeConte, D. rudis Le Conte, and Anchorius lineatus Casey. One species, Diplocoelus angusticollis Horn, is reduced to synonymy with D. brunneus and another, Diplocoelus philothermoides Reitter, is reduced to synonymy with D. rudis. A diagnostic key to species is provided. All species are described and illustrated, and their distributions and relationships are discussed.