Caffenol, where are you located? My best guess would be Mexican bean beetles, or Japanese beetles.

The MBB look similar to lady bugs; if you have them, you would probably find some adults, and their larvae (the most destructive stage) would be present on the underside of the leaves. photos of MBB in all stages Note that the MBB adult has a red thorax, while ladybugs have a black thorax. Ladybug larvae - the good guys - are orange & black.

The black Japanese beetles only attack leaves as adults, and if you have them, they would probably be present in large numbers. photo They are mostly found east of the Mississippi.