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 species is an intermediate-type bluet because of roughly equal amounts of the blue and black on the abdomen. Similar to the boreal bluet and northern bluet, the length of an alkali bluet varies from 1.1 to 1.5 inches. The male's thorax is blue with a black mid-dorsal stripe and black shoulder stripes. The female is similar but with pale colors tan or pale blue and an abdominal pattern with more black.
Found throughout northern and western United States and southern Canada, the preferred habitats for the larvae are not well known. It seems to prefer saline and alkaline waters, although it also has been found at freshwater lakes with little vegetation. This species was documented in Wisconsin for the first time in 2004, in Douglas and Bayfield counties, near the Lake Superior shore.
Throughout its range, the flight season starts in mid-May to late August.