Unicorn Clubtail Dragonfly Habitats: Pointy Crest, Spearpoint Patterns

Summary: North American unicorn clubtail dragonfly habitats get dark-pointed mid-crests, green-yellow thoraxes, pale-streaked legs and red-yellow abdomens.

unicorn clubtail dragonfly (Arigomphus villosipes); Mason Neck West Park, Mason Neck, southernmost Fairfax County, Northern Virginia; Friday, June 3, 2016, 14:10: Judy Gallagher, CC BY 2.0 Generic, via Wikimedia Commons

North American unicorn clubtail dragonfly habitats avoid cultivators, not naturalists, in muddy distribution ranges from Maine through North Carolina, Georgia, Arkansas, Missouri, Illinois, Minnesota, Wisconsin, Ontario and New Hampshire and everywhere in-between.

Unicorn clubtails bear their common name for pointed, square-tipped or tooth-edged mid-crests and tip-widened abdomens and the scientific name Arigomphus villosipes ([crossbow arrow] bolt [is] hairy-legged). Scientific committee consensus in the Dragonfly Society of the Americas, whose 23rd Bulletin of American Odonatology covers Great Plains odonate distributions and diversity, confers common names. Descriptions by Michel Edmond de Selys Longchamps (May 25, 1813-Dec. 11, 1900), husband of Sophie Caroline d'Omalius d'Halloy (Sept. 18, 1818-Dec. 23, 1869), date from 1854.

Unicorn clubtail life cycles expect muddy-bottomed, slow-flowing, sometimes urban-degraded, sparsely vegetated artificial, beaver or semipermanent ponds and small lakes with inlets and streams with quiet reaches.

April through August function as earliest to latest flight seasons even though June and July furnish wildlife mapping opportunities throughout coastal and inland unicorn clubtail niches.

Each unicorn clubtail gets a 10-foot (3.05-meter) shoreline patrol and goes back and forth in fast, low patrols over water with clubbed terminal abdominal segments raised. Unicorn clubtails hanker after daily diets of small-sized dragonflies and daytime perches on algae mats, docks, lilypads, logs, low-lying vegetation, rocks and waterside mud and sand. They incline their abdomens upward to obelisk, interfere with solar exposure and interrupt temperature increases internally and ingest invertebrate prey immobilized within mobile labrum (lower lips).

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

Immature unicorn clubtails keep to dull, muddy lake-, pond-, stream-kind colors even though adults know blue, emerald, gray-green or turquoise eyes and red-, yellow-marked black-brown bodies.

Incompletely metamorphosing life cycles lead from round eggs laid by pollution-intolerant, unaccompanied, unguarded females in slow-flowing waters to larvae, naiads or nymphs and to molted tenerals. Multimolting, nonflying larvae metamorphose into shiny-winged, soft-bodied, weak-flying tenerals that manage permanent colors and physical and sexual maturation before mating and manipulating eggs into ovipositing sites. Aphids, beetles, borers, caddisflies, copepods, crane flies, dobsonflies, gnats, leafhoppers, mosquitoes, rotifers, scuds, water fleas and worms nourish pond clubtail members of the Gomphidae dragonfly family.

North American unicorn clubtail dragonfly habitats offer season-coldest temperatures, north- to southward, from minus 45 to 5 degrees Fahrenheit (minus 42.11 to minus 15 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 unicorn clubtails.

Black horn-like, square-tipped or tooth-edged projections on midcrests, dull gray-green eyes and egg-unclubbed abdomens with egg-filled ovipositors and yellowed lower sides qualify as adult female hallmarks. Males reveal aqua-blue, emerald, gray-green or turquoise eyes, pointed midcrests, black-striped green thoraxes, dense-haired, pale-streaked black legs, clear wings, clubbed red-and-yellow-marked black abdomens and yellow-brown claspers. Adults show off 1.97- to 2.28-inch (50- to 58-millimeter) head-body lengths, 1.46- to 1.61-inch (37- to 41-millimeter) abdomens and 1.14- to 1.41-inch (29- to 36-millimeter) hindwings.

Dark-edged projections on middle crests, green-and-yellow-striped thoraxes and red-and-yellow-marked abdomens tell blue-gray-green-turquoise-eyed, clear-winged, dark-bodied unicorn clubtails from other odonates in North American unicorn clubtail dragonfly habitats.

unicorn clubtail dragonfly (Arigomphus villosipes); Leesylvania State Park, Woodbridge, Prince William County, Northern Virginia; Thursday, July 5, 2012, image by Judy Gallagher, CC BY 2.0 Generic: Preservation Parks of Delaware County @PreservationParksDelawareCounty, via Facebook May 30, 2017

Acknowledgment

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

Image credits:

unicorn clubtail dragonfly (Arigomphus villosipes); Mason Neck West Park, Mason Neck, southernmost Fairfax County, Northern Virginia; Friday, June 3, 2016, 14:10: Judy Gallagher, CC BY 2.0 Generic, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Unicorn_Clubtail_-_Arigomphus_villosipes,_Mason_Neck_West,_Mason_Neck,_Virginia_-_27421719512.jpg; Judy Gallagher (Judy Gallagher), CC BY 2.0 Generic, via Flickr @ https://www.flickr.com/photos/52450054@N04/27421719512/

unicorn clubtail dragonfly (Arigomphus villosipes); Leesylvania State Park, Woodbridge, Prince William County, Northern Virginia; Thursday, July 5, 2012, image by Judy Gallagher, CC BY 2.0 Generic: Preservation Parks of Delaware County @PreservationParksDelawareCounty, via Facebook May 30, 2017, @ https://www.facebook.com/photo.php?fbid=10155490421308013

For further information:

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Available via James Cook University-Medusa @ https://medusa.jcu.edu.au/Dragonflies/openset/displaySpecies.php?spid=1018

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Bright, Ethan. "Arigomphus villosipes (Selys, 1854: 53 as Gomphus) -- Unicorn Clubtail." Aquatic Insects of Michigan > Odonata (Dragon- and Damselflies) of Michigan > Anisoptera Selys, 1854 -- Dragonflies > Gomphidae (Clubtails) > Arigomphus Needham, 1897 (Pond Clubtails).
Available @ http://www.aquaticinsects.org/sp/Odonata/sp_oom.html

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

Preservation Parks of Delaware County @PreservationParksDelawareCounty. "You can identify a Unicorn Clubtail (Arigomphus villosipes) by the horn like spines on the crest between the eyes." Facebook. May 30, 2017.
Available @ https://www.facebook.com/photo.php?fbid=10155490421308013

Sélys-Longchamps, M.Edm. (Michel Edmond) de. "Synopsis des Gomphines: 41. Gomphus villosipes, De Selys." Bulletins de l'Académie Royale des Sciences, des Lettres et des Beaux-Arts de Belgique, tome XXI (Série 1), IIme partie, no. 7: 53. Bruxelles (Brussels), Belgium: M. Hayez, 1854
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/39438405
Available via HathiTrust @ https://hdl.handle.net/2027/uiug.30112112254658?urlappend=%3Bseq=65

"The 2012 USDA Plant Hardiness Zone Map." The National Gardening Association > Gardening Tools > Learning Library USDA Hardiness Zone > USDA Plant Hardiness Zone Map.
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