I have never seen anything like this and once again I am astounded how geometric nature is. I have had this Croton for over 2 years now and she's doing great, except a couple months ago I noticed a strange white circle with concentric rings growing on the underside of one of her leaves. Now, there's one of these rings on 3 different leaves! The only other problem I have had with this plant is that I saw a sharpshooter on it about a week or two ago.
Does anyone know what these white rings are? What I should do about them? also accepting tips about sharpshooters
Thank you so much!

I've heard of those before but I can't remember the name of them. Ladybugs love hunting pests like those if you can get any otherwise get some Neem Oil and dilute in water with some dish soap just enough to mix with the Neem oil and put it in a spray bottle and spray your plants leaves with it.

Those are whiteflies. There are several ways to get rid of them but since you have a single affected plant you can try one of the two following free remedies.

#1, give your plant a through wash with lukewarm soapy water and then take it inside the shower and wash it with water at 70-80F, not more, not less.
#2, grab your vacuum cleaner and remove everything looking remotely suspicious. Just don't be too zealous otherwise you'll make holes in the leaves.

Whiteflies reproduce quickly, so act quickly. Should the infestation worsen, there are other things you can do but now focus on nipping it at the bud.

@AmberLeaf and @ElPolloDiablo
Thank you guys so much for your help, I really really appreciate it! Ill get started on that right away! First I'm going to spray with neem/dishsoap/water solution, then I will give each one of the leaves a thorough wipe down with a paper towel. Ill give her a good warm shower and vacuum after that. Thank you again!!

ElPolloDiablo said:
#2, grab your vacuum cleaner and remove everything looking remotely suspicious. Just don't be too zealous otherwise you'll make holes in the leaves.

Just a thought, but you might want to empty and wash your vacuum cannister and filters afterwards.

nmoasis said:

Just a thought, but you might want to empty and wash your vacuum cannister and filters afterwards.

Whiteflies grow and multiply very quickly because they have an insanely fast metabolism. This also means if they are removed from their source of food (our plants) they will quickly starve to death.
So unless there's a new strain of platic- and/or metal-eating whiteflies the only risk is to have very poor household hygiene.

Good to know El Pollo. I was harkening back to advice I got many years ago about how housecleaners could spread unsavory critters among their clients' houses by not emptying their vacuums between jobs. Yeah, yeah, I know, different critters. Still, given how much plant matter I trail into my house, I wouldn't be surprised if my own vacuum contents could sustain insecticidal life!

I learn so much from you all! Thanks for sharing, especially the idea about the vacuum and clearing it out afterward. Now I know what those are.