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Boreal bluet

Boreal bluet (Enallagma boreale)
Photo © Paul Dacko

Features and Behaviors

FEATURES
Boreal bluets are mostly blue and are found abundantly north of Illinois and up into Canada. Spots behind the eye are large and shaped like a dumbbell. Males have blue eyes capped with black. The thorax is blue in males and sometimes brown in females, with a wide black stripe in the center and a narrow black stripe on each side. There is an umbrella-shaped bar on the 2nd segment of the abdomen, and black rings on the third through fifth segments. The sixth and seventh segments are mostly black. The eighth and ninth segments are blue. The last (tenth) segment, the tip of the tail, is black on top. Females are either brown or blue with similar thorax markings to males. The female abdominal markings are mostly black on top with pale brown or blue spots at the beginning of each of the third through eighth abdominal segments with spots being larger on the eighth segment. The ninth and tenth segments are black on top. Boreal bluets are virtually indistinguishable from Northern and Vernal Bluets, except by magnification of structural differences.

BEHAVIOR
Boreal bluets prey on mayflies and small flies. Males fly over the open water or perch on emerging vegetation. Boreal Bluets form pairs away from the water, sometimes in open wooded areas. The mating duration is around 23 minutes. The females explore sites to lay eggs for around 11 minutes. Pairs lay eggs in tandem on the surface for around an hour or underwater for around 23 minutes. Reproducing adults have a life expectancy of four to 17 days. They are found in ponds and margins of lakes with emerging vegetation, such as cold bog ponds and muskegs (a North American bog or swamp comprised of water, dead vegetation, and usually a layer of moss). Typically restricted to fishless ponds in the East, but not so in the West. They are found along the northern edge of Illinois, just beyond the borders with Wisconsin and Iowa, and northward into Canada. Also distributed throughout the West, including Canada, California, Rocky Mountain uplands, and south into Mexico.

Illinois Range

Taxonomy

​Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Odonata
Family: Coenagrionidae

Illinois Status: common, native