Double-Striped Bluet Damselfly Habitats: Dual-Striped Midline, Shoulder

Summary: North American double-striped bluet damselfly habitats in Canada, Mexico and the United States get blue tips and double-striped midlines and shoulders.

double-striped bluet (Enallagma basidens); G. Richard Thompson Wildlife Management Area, Linden, Fauquier and Warren counties, Northern Virginia; May 12, 2012: Judy Gallagher, CC BY 2.0, via Wikimedia Commons

North American double-striped bluet damselfly habitats appose cultivators along water and naturalists within distribution ranges from Connecticut through Mexico, California, Utah, Colorado, Nebraska, Iowa, Wisconsin, Michigan, Ontario, New York and everything in-between.

Double-striped bluets bear their common name for shoulder stripes and blue colors and the scientific name Enallagma basidens (together [in ovipositing] damselfly [with] basal tooth [clasper]). Common names confirm scientific committee consensus in the Dragonfly Society of the Americas, whose Nick and Ailsa Donnelly fellowship covers DSA meeting travel and travel-related expenses. Scientific designations delve into descriptions in 1902 by Philip Powell Calvert (Jan. 29, 1871-Aug. 23, 1861), President of the American Entomological Society in Philadelphia, Pennsylvania, 1900-1915.

Double-striped bluet damselfly life cycles expect emergent vegetation in, open vegetation near and open water over lakes, ponds, reservoirs and slow reaches of rivers and streams.

February through November function as optimum, southernmost flight seasons even though May through August furnish wildlife mapping opportunities in all Canadian, Mexican and United States' niches.

Double-striped bluets go out between 10 a.m. and 4 p.m., with females getting onto perches away from, and males gripping low-lying perches that give onto, water. Males hover over open water and hunt, but often in swarms, as gleaners, like pond damsels other than sallier dancers, of flushed, opportunistic and stalked prey. Hovering and hunting involve females and males investigating imprisoning food sources within black-striped blue or cream legs and lower lips before late afternoon invokes nightly roosts.

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

Immature female and male double-striped bluets keep dull, faded, light, pale colors and low size ranges even though they know multiple molts between hatching and maturing.

Immature, nonflying double-striped bluet larvae, naiads and nymphs link incompletely metamorphosed life cycles between egg-hatchings on floating filamentous algae or sedges and shiny-winged, soft-bodied, weak-flying tenerals. Tenerals move within 30 minutes of molting to mature within one to three weeks away from water, mate and manipulate eggs into floating in submergent vegetation. 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 double-striped bluet damselfly habitats offer season-coldest temperatures, northward to southward, from minus 25 to 30 degrees Fahrenheit (minus 31 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 double-striped bluets.

Tan eyes; blue, brown, green or tan heads and thoraxes; black double-striped shoulders; and blue-tipped black abdomens with blue W-patterned segments qualify as adult female hallmarks. Immature tan-bodied males retain blue-segmented abdomens whereas adults reveal blue eyes; black-and-blue heads; blue thoraxes with black, paired, thin shoulder stripes; and black spear-patterned, blue-tipped abdomens. Adults show off 0.83- to 1.10-inch (21- to 28-millimeter) head-body lengths, 0.67- to 0.87-inch (17- to 22-millimeter) abdomens and 0.39- to 0.59-inch (10- to 15-millimeter) hindwings.

Black-, double-, fine-striped midlines and shoulders and blue-sided, blue-tipped abdomens tell double-striped bluets from other bluets and related dancers in North American double-striped blue damselfly habitats.

successful predation of double-striped bluet (Enallagma basidens) by robber fly (Asilidae family); Lake Scott State Park, Scott County, west central Kansas; July 6, 2013: Sarah Zukoff (entogirl), 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:

double-striped bluet (Enallagma basidens); G. Richard Thompson Wildlife Management Area, Linden, Fauquier and Warren counties, Northern Virginia; May 12, 2012: Judy Gallagher, CC BY 2.0, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Double-striped_Bluet_-_Enallagma_basidens,_Richard_G_Thompson_Wildlife_Management_Area,_Linden,_Virginia_-_7185755366.jpg

successful predation of double-striped bluet (Enallagma basidens) by robber fly (Asilidae family); Lake Scott State Park, Scott County, west central Kansas; July 6, 2013: Sarah Zukoff (entogirl), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/entogirl/9264326379/

For further information:

Abbott, John C. Dragonflies and Damselflies of Texas and the South-Central United States: Texas, Louisiana, Arkansas, Oklahoma and New Mexico. Princeton NJ; and Oxford UK: Princeton University Press, 2005.

Beaton, Giff. Dragonflies & Damselflies of Georgia and the Southeast. Athens GA; and London UK: University of Georgia Press, 2007.

Berger, Cynthia. Dragonflies. Mechanicsburg PA: Stackpole Books: Wild Guide, 2004.

Bright, Ethan. "Enallagma basidens Calvert, 1902: 114 - Double-striped Bluet." Aquatic Insects of Michigan > Odonata (Dragon- and Damselflies) of Michigan > Zygoptera Selys, 1854 > Coenagrionidae, Kirby, 1890 (Pond Damselflies) > Enallagma Selys, 1875 (Bluets).
Available @ http://www.aquaticinsects.org/sp/Odonata/sp_oom.html

Calvert, Philip P. (Powell). "8. Enallagma basidens, sp. n." Biologia Centrali-Americana: Insecta. Odonata (Forming Introduction and Pages 17-420 of Volume "Neuroptera"): 114. London, England: R.H. Porter; Dulau & Co., 1902
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/595867
Available via HathiTrust @ https://hdl.handle.net/2027/mdp.39015061414291?urlappend=%3Bseq=138

"Enallagma basidens." James Cook University-Medusa: The Odonata - Dragonflies and Damselflies > Zygoptera > Coenagrionidae > Enallagma.
Available via James Cook University-Medusa @ https://medusa.jcu.edu.au/Dragonflies/openset/displaySpecies.php?spid=3649

Kickin Chicken Photography @KickinChickenPhotography. "Double-striped Bluet in the backyard." Facebook. Aug. 9, 2015.
Available @ https://www.facebook.com/photo.php?fbid=869210379839002

Paulson, Dennis. Dragonflies and Damselflies of the East. Princeton NJ: Princeton University Press, Princeton Field Guides, 2011.

"The 2012 USDA Plant Hardiness Zone Map." The National Gardening Association > Gardening Tools > Learning Library USDA Hardiness Zone > USDA Plant Hardiness Zone Map.
Available @ https://garden.org/nga/zipzone/2012/