The bluets form a group of about 17 similar species in Wisconsin in which the males usually share the characteristics of having blue and black stripes on the thorax, and blue and black markings on the abdomen. In-hand examinations are usually needed to identify them, although they can be grouped into subcategories based on the amount of black showing on the abdomen. Males are easily identified, under magnification, by the shape of their terminal appendages. Females are generally duller than males, and they are more difficult to identify, which is accomplished by subtle differences in the shape of the mesostigmal plates on the top of the thorax. Generally, males are bright blue while the females are green or yellow-green or blue. There are some species that are yellow-orange, a mix of various colors, or black with some blue.
The male of this strikingly colored species is a black-type bluet because of its predominantly black abdomen on top. The body length of the rainbow bluet varies from 1.1 to 1.3 inches. With an orange face and the top of the eyes blue, the males thorax has black shoulder stripes, greenish sides, and yellow legs with small black stripes. The abdomen is greenish on the sides with dorsal black markings and blue on the tip. The blue tip has a black spot. The female is similar except for the color which is pale yellow green. The tip of the female's abdomen is black with a small pale spot.
Ranging from central to eastern United States and southeast Canada, this species prefers ponds, slow streams, or lakes near stream inlets or outlets, with abundant emergent vegetation. In Wisconsin, it is fairly common and widely distributed throughout most of the state.
Typical flight season is from early June to late July in Wisconsin.