What specialized anatomical feature protects the frog's eye without obstructing vision while resting?

Answer

The nictitating membrane

They possess a third eyelid, the nictitating membrane, which protects the eye while allowing the frog to remain aware of its surroundings.

What specialized anatomical feature protects the frog's eye without obstructing vision while resting?
taxonomyanimalclassificationfrogTree Frog