Here in northern Illinois, we have some kind of mutant ladybug that will bite like a biting fly if it lands on you.
That sounds like the Asian Lady Beetle or “Japanese ladybug.” Some varieties look almost identical to domestic ladybugs, but they’re a lot more aggressive (thus the bite). Some versions are supposed to have a stink-juice defense, too.
I ran afoul of some little green shield shaped bugs in Eastern Montana that bit—and it burned when they did. I never found out what they were, but it was pretty unpleasant.