Diadophis punctactus arnyi, also known as the prairie ringneck snake, is a subspecies of small, thin snake in the family Dipsadidae.
D. p. arnyi has a black-grey head, a grey body, and an orange ring around its neck. The ring does not extend toward the underside. The underside is yellow for a third of the body, orange for another third, and red for the last third. The belly also has black flecks along it. This snake has a blunt head, a tiny mouth, and small eyes. Anteriorly the dorsal scales are usually in 17 rows (other eastern subspecies have 15 rows). A mature prairie ringneck grows to about 25–36 cm (9.8–14.2 in) in total length (including tail), record 42 cm (16 1⁄2 in).
The prairie ringneck snake (as its name suggests) lives in or near prairies and can often be found sunbathing or slithering out in the open. It can also be found under old logs, rocks, pieces of wood and sheets of tin. It likes to live under dead leaves and foliage in the woods, and in grasses in the prairie.
D. p. arnyi is very common within its range and can be found almost anywhere in Midwest North America, i.e., Iowa, Kansas, Missouri and northwestern Arkansas to South Dakota, Oklahoma and Texas.