Saturday, July 21, 2018

Brown Spiketail Dragonfly Habitats: Dark Face and Legs, Paired Triangles

Summary: North American brown spiketail dragonfly habitats get blue eyes barely touching, brown bodies, paired stripes and triangles and spiked ovipositors.

brown spiketail dragonfly (Cordulegaster bilineata): Mike Ostrowski, CC BY SA 2.0, via Wikimedia Commons

North American brown spiketail dragonfly habitats anchor cultivators poorly in boggy soils but naturalists promisingly within distribution ranges from New Jersey through Alabama, Tennessee, Kentucky, Illinois, Michigan and Pennsylvania and everywhere in-between.
Brown spiketails bear their common name for background coloration and spiked ovipositors and the scientific name Cordulegaster bilineata (club-shaped belly [and] two narrow, thoracic, yellow side-stripes). Common names cap scientific committee consensus in the Dragonfly Society of the Americas, whose third Bulletin of American Odonatology considers corporal skimmers and forktail pond damsels. Scientific designations delve into descriptions in 1983 by Frank Louis Carle, Professor of Aquatic Entomology at Rutgers, The State University of New Jersey, in New Brunswick.
Brown spiketail dragonfly life cycles expect boggy, mucky or sandy sunlit seeps and trickles and imperceptibly to obviously flowing small sunny streams with open waterside woodlands.

March through July function as earliest to latest flight seasons even though April or May furnishes wildlife mapping opportunities for all North American brown spiketail niches.
Female and male brown spiketail dragonflies go to cool, daytime, near-ground hunting, patrolling and pre-mating niches in waterside woodlands and to evening and night-time resting roosts. They hang at angles of 45 degrees to low-lying perches on weedy stems and twigs, head back and forth over the same short stretches and hover. Immobilizing prey within dark, three-segmented legs and strong lower lips and identifying mates inspire intensive investigations with the same itineraries albeit atypically spiketail-like in wary inconspicuousness.
Ants, biting midges, ducks, falcons, fish, flycatchers, frogs, grebes, lizards, robber flies, spiders, turtles and water beetles and mites jeopardize North American brown spiketail dragonfly habitats.

Immature brown spiketail dragonflies keep dull, faded, light, pale colors on small bodies even though mature females and males know dappled-like browns, greens, whites and yellows.
Incompletely metamorphosing life cycles link brown spiketails as eggs laid by females' bouncy, sewing machine-like, up-and-down abdominal motions, as larvae, naiads or nymphs and as tenerals. Multi-molting, nonflying immature brown spiketails molt into shiny-winged, soft-bodied, weak-flying tenerals whose physical and sexual maturation manifests itself in mating and manipulating eggs into ovipositing sites. North American spiketail members of the Cordulegastridae family need aphids, beetles, borers, caddisflies, copepods, crane flies, dobsonflies, gnats, leafhoppers, mosquitoes, rotifers, scuds, water fleas and worms.
North American brown spiketail dragonfly habitats offer season-coldest temperatures, northward to southward, from minus 45 to 20 degrees Fahrenheit (minus 42.11 to minus 6.66 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 brown spiketails.
Black-crossbanded white faces, blue- or white-green eyes, clear wings, double side- and single- shoulder-striped brown thoraxes and paired triangle-patterned brown abdomens qualify as adult female hallmarks. Adult males reveal the same blue-green, brown, white, white-green and yellow combinations as mature females whose unclubbed abdomens remain thicker from retaining eggs and spiked ovipositors. Adults show off 2.16- to 2.68-inch (55- to 68-millimeter) head-body lengths, 1.65- to 2.05-inch (42- to 52-millimeter) abdomens and 1.34- to 1.69-inch (34- to 43-millimeter) hindwings.
Brown bodies, eyes briefly touching and paired yellow abdominal triangles and thoracic stripes tell brown spiketails from other odonates in North American brown spiketail dragonfly habitats.

brown spiketail dragonfly (Cordulegaster bilineata); photo by Rusty Moran/SmugMug: ChungKristinas @ChungKristinas via Twitter March 25, 2016

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

Image credits:
brown spiketail dragonfly (Cordulegaster bilineata); St. Mary's County, Southern Maryland; April 30, 2011: Mike Ostrowski, CC BY SA 2.0, via Wikimedia Commons @
brown spiketail dragonfly (Cordulegaster bilineata); Occoquan Regional Park, Fairfax County, Northern Virginia; photo by Rusty Moran/SmugMug: ChungKristinas @ChungKristinas via Twitter March 25, 2016, @

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; Oxford UK: Princeton University Press, 2005.
Beaton, Giff. Dragonflies & Damselflies of Georgia and the Southeast. Athens GA; London UK: University of Georgia Press, 2007.
Berger, Cynthia. Dragonflies. Mechanicsburg PA: Stackpole Books: Wild Guide, 2004.
Bright, Ethan. "Cordulegaster (Zoraena) bilineata (Carle, 1983: 61 as Zoraena) -- Brown Spiketail." Aquatic Insects of Michigan > Odonata (Dragon- and Damselflies) of Michigan > Anisoptera Selys, 1854 -- Dragonflies > Cordulegastridae Newman, 1853 (Spiketails) > Cordulegaster Leach, 1838 (Spiketails).
Available @
Carle, Frank Louis. "A New Zoraena (Odonata: Cordulegastridae) from Eastern North America, with a Key to the Adult Cordulegastridae of America." Annals of the Entomological Society of America: 76, no. 1 (January 15, 1983): 61-68. Cary, North Carolina: Oxford University Press, 1983.
Available via Oxford University Press @
ChungKristinas @ChungKristinas. "Brown Spiketail Dragonfly." Twitter. March 25, 2016.
Available @
"Cordulegaster bilineata." James Cook University-Medusa: The Odonata - Dragonflies and Damselflies > Anisoptera > Corduligastridae > Cordulegaster.
Available via James Cook University-Medusa @
Paulson, Dennis. Dragonflies and Damselflies of the East. Princeton NJ: Princeton University Press, Princeton Field Guides, 2011.

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