We have huge problems w/ those beetles, if they're the same ones anyway, but not problems w/ them on plants, they don't cause any harm that I know of. We called them asian beetles, b/c they are similar to lady bugs, but were imported to eat aphids and such on soybeans...I'm all for bio-control, but this wasn't the best application of it in my book. From what I've heard they get 'bored' easily and leave the fields...and I grew up living w/ fields all around - guess where they go To!They aren't as adapted as the usual lady bugs, so the second it gets cool outside, they swarm inside, and they stink Horribly!!! You can't squish them or disturb them in any way w/o them letting off a terrible smell And they collect near lights, meaning windows, but overhead lights as well, like a hanging light over your kitchen table - and they sometimes Fall Off of smooth surfaces, into your food and drink, and then stink b/c they were disturbed ...My advice, if they're the same kind, get some sort of bug spray, turn on a vac. and spray it into the vac right before sucking up the beetles. That Usually reduces the stink and then kills them if you don't empty the bag right away. ...I'd much rather have swarms of non-smelly real lady bugs in my house, but they stay outside and prefer piles of leaves for the winter!
....also someone on a natural history list I belong to found out that she (and a good number of other people) were having allergic reactions to them. they were in her walls, and that was enough to trigger allergies.
Unless you are dome shaped and orange with spots, the bugs don't look like you. Not only do they stink a bit, they can bite, unlike the nice friendly red american ladybugs. Thanks all for the information.