Onthophagus skelleyi Sánchez-Huerta, Zunino, and Halffter, new species, of the chevrolati species-group, hippopotamus line and complex, is described and illustrated. To the best of our knowledge, all of the species in this complex are associated with rodent (Geomyidae) burrows. The new species was found in northern Querétaro, Mexico, in the northeastern portion of the distribution area of the hippopotamus complex. The affinity of O. skelleyi with Onthophagus coproides Horn and Onthophagus hippopotamus Harold are discussed. An updated key to the species of the hippopotamus complex is also provided.