What essential anatomical feature does the Speckled Kingsnake lack compared to a true rattlesnake?

Answer

A keratinous rattle

While the Speckled Kingsnake mimics the sound, it does not possess the keratinous rattle characteristic of a true rattlesnake.

What essential anatomical feature does the Speckled Kingsnake lack compared to a true rattlesnake?
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