Damselflies (order Odonata, suborder Zygoptera) look a lot like dragonflies (order Odonata, suborder Anisoptera). One notable feature that separates them is that damselflies rest with their wings vertically above their backs while dragonflies rest with their wings held horizontally. Damselflies also tend to be smaller and thinner, and have eyes that are widely separated.
A number of these broad-winged damselflies (family Calopterygidae) were buzzing around the edge of the River Raisin near Blissfield Michigan. They kept resting for a few seconds on some fallen branches, giving me brief opportunities to photograph them.
You usually find damselflies near the water. The young nymphs are aquatic, vaguely resembling wingless adults. The nymphs are carnivorous and eat a variety of aquatic invertebrates, including mosquito larvae. With each molt, the nymphs become more and more adultlike before finally leaving the water as fully-developed adults. They then feed on adult insects, including mosquitoes, and mate. Females lay their eggs in the water, and the process repeats.