I'm a newbie gardener and in the past 2 weeks have had some issues I'm trying to solve. First my cucumbers had a light powder coating. They're Diva which I thought were resistant to mildew. I've sprayed them a couple times with insecticidal soap and baking soda, and that seemed to have gone away. Now the lower leaves are just mottled with yellow spots. Undersides are fine. They do eventually die (shrivel up brown and die) along the bottom. Now, I've noticed some of my squash (right next to cucumbers) also have this.

Now yesterday, I've noticed the cucumber leaves, squash leaves (same 4x4 bed) and eggplant and beans (nearby but different 4x4 bed) all have holes eaten in them, with brown thin patches and some white splotches (excrement??). Doing some googling brought me to the idea that it was cucumber beetles that gave them bacteria wilt!

I've been out this morning looking and have found no such beetles.

The only thing I found was this one..which when I look in my books and online doesn't look like a squash beetle (I don't think anyways). Could this be causing my problems?? Does anyone know what this is? He was sitting on my eggplant leaes this morning.