This black and blue damselfly is distinguished by the bright yellow marks on the lower sides of thorax. Its wings are partly spread when perched, which is a distinct characteristic from other damselflies in this family. The female's pattern is similar to the male's, but light brown to gray compared to blue in the male. The length of the body varies from 1.2 to 1.5 inches.
Known throughout eastern United States and parts of Canada, this species is usually found at small,vegetated, spring-fed brooks and streams, swamps, spring pools, and clean ponds or lakes. This damselfly does not move much in its adult stage and it is common throughout Wisconsin.
Late May to late July in Wisconsin.