Something is eating my orange, grapefruit, lemon, and peach tree leaves, but it is not touching my banana trees; SW Florida.
Orange tree leaves chewed:
Grapefruit tree leaves chewed:
Grapefruit tree losing leaves:
Peach tree leaves chewed:
The only insects I have noticed on the tree is this, and each are about 1/2 inch long:

I've just about exhausted my efforts trying to figure out what kind of insect it is. Looks beetle-like.
I have not yet applied any type of insecticide; I don't really know what to apply or if I even should apply any.
What are these white insects?
Could they be the culprits eating my leaves?
How to stop the culprits?
Thanks!