Larry, What a lovely green lacewing you have there. I love green lacewings and think it would be hard to garden organically without them because they are voracious eaters of pest insects. Mark, It is one of the assassin bugs, as Helen said, and is related to the wheelbug. Almost all assassin bugs are good as they prey upon pest insects. There's about 150 known kinds of assassin bugs in North America, and the only one I can think of that is bad (from a human point of view) is the kissing bug, aka the cone-nosed assassin bug, because those do bite people. Some assassin bugs, and in particular the wheelbug, will bite a human if that human gets too close to it, but they are only doing that as self-defense. Wheelbug bites can be very painful---similar to a scorpion bite. Dawn

Mayfly. An adult aphid looks exactly like one that has just been born, only bigger. Aphids do not undergo a complete metamorphosis as some insects do.

I'm not going to discard any of my plants because of these, and don't think you should either. Their involvement with plants is transient, seasonal, not an indefinite infestation. This is about crops, but the graphic of their life cycle is helpful. Once the last generation hatches into winged adults, they fly away to hibernate. Similar to how butterflies work.

It belongs to the insect order Diptera. Common members of that group are flies, mosquitoes, midges, crane flies. Your creature doesn't fit the size or shape of potential pests of the order Diptera. Usually, very small fellows such as yours are simply part of the food chain. So, you say that you have a cloud of them flying in the yard. Sounds like a recent emergence of non-pests.