mud snake

a long, bluish-black colubrid snake (Farancia abacura) with a red belly, and a nonpoisonous spine at the tip of the tail, found in the SE U.S.

See mud snake in American Heritage Dictionary 4

noun
A burrowing snake (Farancia abacura) of swamps and lowlands of the southeast United States, having black scales with reddish markings.
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