- indigo snake, gopher snake, Drymarchon corais - large dark-blue nonvenomous snake that invades burrows; found in southern North America and Mexico
--1 is a kind of colubrid snake, colubrid
--1 has particulars: eastern indigo snake, Drymarchon corais couperi - gopher snake, Pituophis melanoleucus - bull snake of western North America that invades rodent burrows
--2 is a kind of bull snake, bull-snake