Big Bluet Damselfly Habitats: Bars Near Spots, Spear-Patterned Abdomens

Summary: North American big bluet damselfly habitats from coastal Maine through Mexico and in Tennessee get bars near eyespots and spear-patterned abdomens.

male big bluet damselfly (Enallagma durum); Occoquan Bay National Wildlife Refuge, Woodbridge, Prince William County, Northern Virginia; Sept. 4, 2016: Judy Gallagher (judygva), CC BY 2.0, via Flickr

North American big bluet damselfly habitats await brackish and coastal wetland-loving arborists, gardeners, naturalists and tree stewards within distribution ranges along Atlantic and Gulf coastlines from Maine through Mexico and in Tennessee.

Big bluets bear their common name as North America's largest bluet and for blue colors and the scientific name Enallagma durum (different [from Coenagrion and] hard). North America's bluets cluster into the Coenagrion (together [tandem ovipositing] damselfly) genus comprising more Eurasian temperate, than American northernmost, species or the primarily American Enallagma genus. Scientific designations discern descriptions in 1861 by Hermann August Hagen (May 30, 1817-Nov. 9, 1893), brother of mathematics professor Robert Hagen (Sept. 15, 1815-Aug. 19, 1858).

Big bluet damselfly life cycles expect the brackish waters of estuaries and lower reaches of slow coastal plain rivers and the sandy waters of large lakes.

February through December function as maximum, most southerly flight seasons even though July and August furnish wildlife mapping opportunities throughout all Mexican and United States' niches.

Female big bluet damselflies go for shoreside-grounded perches on such emergent vegetation as grass, rush and sedge beds whereas big bluet males go to riverside perches. They hunt as gleaners, like pond damsels other than sallying dancers, by heading from foraging perches after low-flying, low-lying passersby and by harvesting flushed, opportunistic prey. Immobilizing food sources within black-spurred, black-striped pale legs and lower lips is a daytime activity until late afternoon impels females and males back to night-time roosts.

Ants, assassin flies, biting midges, ducks, falcons, fish, flycatchers, frogs, grebes, lizards, spiders, turtles and water beetles and  mites jeopardize North American big bluet damselfly habitats.

All immature big bluets keep dull, faded, light, pale colors and small sizes even though adults know blue-colored male or blue-, brown- or green-colored female bodies.

Eggs laid underwater by upside-down females lead to nonflying larvae, naiads or nymphs and to shiny-winged, soft-bodied, weak-flying tenerals that leave watery locations within 30 minutes. Tenerals manage permanent colors and sexual maturation within seven to 21 days of manifesting themselves as emerged adults from the little adult-like, immature stage's last molt. Bluet members of the Coenagrionidae pond damsel family need aphids, beetles, borers, caddisflies, copepods, crane flies, dobsonflies, gnats, leafhoppers, mosquitoes, rotifers, scuds, water fleas and worms.

North American big bluet damselfly habitats offer season-coldest temperatures, northward to southward, from minus 15 to 30 degrees Fahrenheit (minus 37.22 to minus 1.11 degrees Celsius).

Beech, bellflower, birch, bladderwort, cattail, daisy, grass, greenbrier, heath, laurel, madder, maple, nettle, olive, pepperbush, pine, pondweed, rush, sedge, water-lily and willow families promote big bluets.

Blue carinas (upper ridges); dark-topped tan eyes; blue, brown or green thoraxes with pale line-divided black median stripes; and black abdomens qualify as adult female hallmarks. Males reveal black-capped blue eyes and heads; dark-striped blue faces; black-ringed, black-striped, blue-ridged blue thoraxes; black-striped blue to tan legs; and black-marked, black-spotted, blue-tipped blue abdomens. Adults show off 0.94- to 1.73-inch (24- to 44-millimeter) head-body lengths, 1.10- to 1.38-inch (28- to 35-millimeter) abdomens and 0.67- to 0.98-inch (17- to 25-millimeter) hindwings.

Occipital bars near pale eye spots, brackish habitats and spear- or torpedo-patterned abdomens tell big bluets from other damselflies in overlapping North American big bluet damselfly habitats.

female big bluet damselfly (Enallagma durum); Leesylvania State Park, Woodbridge, Prince William County, Northern Virginia; July 30, 2011: Judy Gallagher (judygva), CC BY 2.0, via Flickr

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

male big bluet damselfly (Enallagma durum); Occoquan Bay National Wildlife Refuge, Woodbridge, Prince William County, Northern Virginia; Sept. 4, 2016: Judy Gallagher (judygva), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/52450054@N04/30338034633/

female big bluet damselfly (Enallagma durum); Leesylvania State Park, Woodbridge, Prince William County, Northern Virginia; July 30, 2011: Judy Gallagher (judygva), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/52450054@N04/7538391804/

For further information:

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Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/1321559
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