Yes, looks like Serica fimbriata. If you had a guava or anything closely related you would have nothing but bare branches, but they prey on avocado, persimmon, and apple too.
The worst part is that they lay their larvae in the ground to feed on the roots of the trees they defoliate leading to a cycle of stunting that is very difficult to break.
This year I was able to do some damage to them by spreading worm castings under the trees they feed most heavily on. This seems to break the cycle because the worm castings contain chitinase, an enzyme which breaks down insect exoskeletons.
I'm likely going to have to apply it regularly to see lasting results, but I'd strongly recommend you try it. There's no product in my state which is registered against this pest and actually stands a chance of making a difference.