Northern Diamond-Backed Watersnake
Of the seven types of watersnakes native to Missouri, the diamond-backed is the largest. The common name is derived from the light areas along the snake's back, which may be shaped like diamonds. The overall color may be light brown or dull yellow, with dark brown markings on the sides and back. Two rows of dark brown half-moons border the yellow belly. Scales along the body have keels, which cause watersnakes to feel rough.