Zucchini and delicata squash have these very strange silver grey bugs that are definitely sucking the juices out of the plants. I have never in my 40 years of gardening seen anything even remotely like these things. There can be up to a hundred in a cluster, ranging from small ones the size of an aphid to large ones almost an inch long. There bodies are oval and soft. They do not fly and they have black legs. Have dusted them directly with an organic pesticide and not a single one died!