This is the second year I'm seeing these little pests. Can anyone tell me what they are? I don't know what they do exactly, but they are ALL OVER my pumpkins. I've had my veggie garden going for months now, and these bugs only just appeared. They didn't come last year until the pumpkins were about the size they are now (hand on pumpkin in photo for reference), and they stay away from every other plant in the garden (currently just tomatoes, zucchini, yellow squash, peppers, and carrots).
They seem to multiply rapidly. My pumpkins all spontaneously died last year, and I'm not sure if it had to do with these bugs. Once the plants were dead and the pumpkins shriveling up, all you could see were literally dozens of these bugs perched on them.
The little gray ones seem to be the young'uns. They are always trailing the larger bugs. They're about 3/4" long and have wings, but can't seem to fly very far.