The new blissid genus Wheelerodemus is described to accommodate the new species W. muhlenbergiae, based on specimens collected on the grasses Muhlenbergia lindheimeri and M. reverchonii from the Arbuckle Mountains in southcentral Oklahoma and the Edward's Plateau in westcentral Texas. Because the size of specimens from Oklahoma appeared consistently smaller than those from Texas, samples from each area were sequenced using the COI barcode region to help determine that only one variable species was involved. Diagnoses, descriptions, a color habitus illustration of the adult male, dorsal and lateral photographs of the adult male and female, photomicrographs of selected structures, illustrations of male and female genitalia, and a key to the U.S. blissid genera are provided to help distinguish this new genus and species from other Blissidae.