The western ribbonsnake averages 20 to 30 inches in length. It has a pair of large, light-colored spots on the head, a black back and an orange stripe in the middle of the back. Light stripes are found along the length of the body on the sides. The belly and chin are green-white. The scales are keeled (ridged). The body is very slender with the tail more than one-fourth of the body length.
The western ribbonsnake may be found in the Illinois counties that border the Mississippi River, southwestern Illinois and rarely in other locations scattered throughout the state. It lives in and around streams, ditches, marshes, edges of ponds and lakes and sometimes in upland woods. This semiaquatic animal moves quickly, climbing and swimming easily. It is active during the day in spring and fall, becoming nocturnal in the hottest summer months. When alarmed, it may flatten its body and release an unpleasant musk from the glands at the base of its tail. The western ribbonsnake may hibernate in rock crevices with other snake species.