Two new Mexican species of aphodiine Scarabaeidae are described: Ataenius paraperforatus new species (Eupariini), based on specimens of both sexes collected in mesophilous cloud-forest of Xilitla, Queretaro State, Jacala, Hidalgo State, and Totutla, State of Veracruz; and Cephalocyclus stebnickae new species (Aphodiini), based on two male specimens captured in a Pinus-Quercus forest near Teopisca, Chiapas State. Ataenius paraperforatus is compared to A. perforatus Harold. Important taxonomic characteristics of both Ataenius as well of the new Cephalocyclus are illustrated. A key for the identification of the seven known species of Cephalocyclus and comments on the species distribution in Mexico is additionally presented.