The midland brown snake is a close relative of the northern red-bellied snake. The general color is gray-brown to reddish-brown, with a white or yellowish belly. Its back has a distinct tan stripe bordered by two rows of small, dark brown spots; the spots normally are joined by small lines across the tan stripe.
A similar subspecies, the Texas brownsnake (Storeria dekayi texana), is found in the western third of Missouri. Its ground color is often reddish brown, and the short bars between the small dark spots along the back are thinner and less obvious. Also, the dark spot on either side of the neck is larger. Where the two subspecies overlap, many snakes show intermediate characteristics.