I am trying to learn my aquatic insects. I observed these today on a small, fast flowing mountain stream in Southern CA. The only book on entomology I have is Hatch Guide For Western Streams. I believe this is a small brown stonefly.
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Sorry for the bad picture on this one. And, it's a little beat up cuz I had to whack it out of the air with my hat. These weren't very impressive looking like blue winged olives. They just kind of hovered a few feet above head. I don't see anything in my book that looks like this with those crazy eyes and nasty looking anal hooks. Any ideas?
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This next one I didn't see flying. I found it on a rock. It is really small, about 1/2 the size of the monster above. And the picture has a yellow tint because I took it indoors. The 2 tails is throwing me because most of the mayflies in my book have 3.
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I know this next one is a terrestrial, but I've never seen anything like this beetle before. These were SWARMING on a few small trees beside the water. They were absolutely devouring the leaves. They had a nice shiny metallic green body. Unfortunately, it doesn't show up well under my crappy indoor lighting. It is 1/4" in length. I've seen Japanese beetles do this on the east coast, but they were brown.
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Any help is greatly appreciated.