The medium-sized, dark brown striped emeralds have some pale markings on the thorax and abdomen, black legs, clear wings and brilliant green eyes. The thorax has a metallic bronze-green sheen and the abdomen is dark metallic black-green. Most species are uncommonly seen, but this may be largely due to their secretive nature. When flying, most species look alike which is why in-hand identifications of their anatomical features are often needed.
This emerald varies from 1.9 to 2.0 inches in the length. The thorax has two bright lateral stripes on each side. The abdomen has few markings except near the end of the abdomen for the males. Females have yellow lateral stripes along most of the abdomen. The face is yellow. The female ovipositor is a short perpendicular spout.
Found in northern mid United States, especially northern Great Plains, the plains emerald prefers small prairie or woodland streams and ditches. This species is known in Wisconsin from just a few eastern counties.
Throughout its range, the typical flight season is from mid-June to mid-August.