What characteristic behavior results from the May beetle's specific diet and life cycle timing, often confusing observers?

Answer

Chewing damage is seen on leaves, but the beetles are gone by morning

Adult beetles feed at night, and since they return underground to rest during the day, observers cannot locate the source of the chewing damage seen on leaves.

What characteristic behavior results from the May beetle's specific diet and life cycle timing, often confusing observers?
dietanimalinsectbeetle