Numbers
4 Families:
Broad-winged: Calopterigidae
Spread-winged: Lestidae
Threadtails: Protoneuridae
Pond Damsels: Coenagrionidae
Identification
Forewing and hindwing similar size and shape, held at rest above body (except Spreadwings.) Very slender abdomen. Male has four terminal appendages and female has well-developed ovipositor.
(1)
Broadwinged damsels (Jewelwings, Rubyspots) have wider wings than Pond Damsels and may have colored or spotted wings (most Pond Damsels have clear wings except for pterostigma.)
Spreadwings are readily identified because they do not fold the wings together snugly--they also typically "hang" from a perch, with wings slightly spread.

The Great Spreadwing is our largest damselfly.
Males and females are typically different in color, with the male showing more brilliant color, though some female damsels are also brightly colored. In some species females have both a male-form and a female-form color pattern.
(2) plate 6f and others.
Identification is made by noting details of markings on head, thorax, and abdomen.
Habitat
Damselflies require water for reproduction, and are often found near ponds, streams, etc., but some species may be found at a distance from water, especially near the ground in grass, woods, etc.
Season
Generally, warm weather. Some emerge early in spring, others in midsummer; in many locations, species follow a sequence through the warm part of the year.
Food
Damselflies are predators on smaller invertebrates.
See Also
Dragonflies, suborder Anisoptera, usually hold wings spread at rest.
Print References
Borror & White, pp. 74-75
(1)Internet References
Odonata Central This excellent guide covers North America including Canada and Mexico, and includes checklists down to county, maps, and many images.
Dragonflies and Damselflies of the United States This is also an excellent site but covers only the United States and not all species are illustrated.
Dragonfly Biodiversity Dennis Paulson's excellent odonate site, with many maps, images, and checklists.
West Virginia Zygoptera Site with images and some life history information.
Southwest Dragonflies - Information and images.