Brownr26: Welcome to the Forum from "across the Pond," from another Colony! LOL. I am a huge Oriental Lily grower. SOOBY nailed it already, and others contributed, the pictures shown are of the individual, well hatched "Lily Beetles" and will turn brilliant red if you have not squished same already. There actually are two treatments for "Lily Beetles"! Here is my experience. Early Spring as soon as the lilies start to poke through the soil or shortly thereafter, get out there with your strongest eyeglasses (only to spot/detect the little btd's when they drop to the ground-which they will when you try to pick them off) and squash them. I have this theory that if I leave squashed lily bugs everywhere, eventually the birds might learn to do it for me-just a theory! LOL. Secondly, I participated last year in a Canadian/US study introducing a tiny parasitic wasp, under controlled conditions, to one bed of Oriental lilies.The wasp, the size of a black fly, attacks the first blackish looking goo on the underside of the leaves (from which a bunch of those teenage specimens you pictured emerge), effectively parasitically (better way to phrase that) killing the beetles long before the stage at which your pic illustrate. I have to say, there appears to be a decided difference in the number of Lily beetles in that bed! Way fewer! Initially, pick them off as others have suggested! Cheers!