Which physical feature helps distinguish the racer from the Eastern Cottonmouth (Water Moccasin)?

Answer

The racer has smooth scales and lacks obvious heat-sensing pits.

Key identifiers separating the racer from pit vipers like the Cottonmouth are the racer’s slender body, long head, smooth scales, and absence of heat-sensing pits.

Which physical feature helps distinguish the racer from the Eastern Cottonmouth (Water Moccasin)?
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