Illinois
Snakes in Adams County
15 species have been documented here, 2 of them venomous.
Venomous snakes in Adams County
Full guide & what to do if bitten →
Timber RattlesnakeCrotalus horridusVenomousHeavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Eastern MassasaugaSistrurus catenatusVenomousStout, dark-blotched body, nine large scales on the crown, and a small rattle.
Every snake recorded in Adams County
Common Watersnake
Nerodia sipedon
Harmless
Gray Ratsnake
Pantherophis spiloides
Harmless
Common Garter Snake
Thamnophis sirtalis
Harmless
DeKay's Brownsnake
Storeria dekayi
Harmless
North American Racer
Coluber constrictor
Harmless
Eastern Hognose Snake
Heterodon platirhinos
Harmless
Timber Rattlesnake
Crotalus horridus
Venomous
Ring-necked Snake
Diadophis punctatus
Harmless
Western Ratsnake
Pantherophis obsoletus
Harmless
Plain-bellied Watersnake
Nerodia erythrogaster
Harmless
Western Ribbon Snake
Thamnophis proximus
Harmless
Diamondback Watersnake
Nerodia rhombifer
Harmless
Eastern Massasauga
Sistrurus catenatus
Venomous
Prairie Kingsnake
Lampropeltis calligaster
Harmless
Graham's Crawfish Snake
Regina grahamii
Harmless
Compiled from verified GBIF & iNaturalist observations. Informational only.