cucumber beetle larvae

Hi, I transplanted a dozen pumpkind plants and a dozen melon plants 8 days ago in my garden. They looked to be doing fine about 3 days later. Yesterday, from outside the fence, they looked like they were drooping a bit, so I gave them a good shot of water (drip irrigation). They looked worse today, and on further inspection, the new leaves forming on the plants are dead, the larger more mature leaves are yellowing/whitening around the edges, and are very brittle, the edges just disintegrate if you touch them. Looking at the underside of the leaves, there looks to be an insect that looks like a gnat, very small and black, a few on each leave. Other leaves have a cluster of these that look like black eggs, you touch them and they break, leaving black on your finger, like a blackberry would do. Some of my tomato plants look a little wilty too, some of these gnat looking things are on them, which confuses me because tomatoes are a completely different family than melons/pumpkins. I just planted 30 pepper plants this morning, and am hesitant to move forward to the heirloom tomatoes if this is something that could spread from plant to plant. Anyone have any ideas what this is or what to do about it? Thanks in advance, Miller.

Another picture of the infected leaf

Earwigs have pincers though and these don't seem to have that.