First, ask yourself, is it anything I did differently by putting something new into the soil or on the leaves? Next, have you sprayed any weed killers near the plumeria?

If no to the above, then it's probably insects of some kind.

Thanks tunatony. Non of the above.

Dave, they are in the ground.

That damage is very similar to leaf hoppers. They like to hang out along leaf stems and underside of leaves. Usually spraying neem oil on the bottom sides of the leaves can get them to move on down the road. Existing damage is there until the leaves fall off so concentrate on new growth to see if the problem is on going.

Thanks the_first_kms2(8/9). I will do the neem oil treatment this weekend.