Members of the Prionus genus are large and usually brown or black. All members of the genus Prionus have twelve or more strongly toothed or even flabellate antennomeres on their large antennae. Common North American species include the "tile-horned Prionus", Prionus imbricornis, the "California root borer", Prionus californicus, and the "broad-necked root borer", Prionus laticollis.