Sunday, February 18, 2018

Vesper Bluet Damselfly Habitats: Green, Orange, Yellow Evening Fliers


Summary: North American vesper bluet damselfly habitats in Canada and the United States get black, blue, brown, green, orange, yellow bodies flying evenings.


vesper bluet damselfly (Enallagma vesperum); Grand River at Glenshire Road, Summit Township, Jackson County, south central Michigan; Aug. 15, 2014: Don Henise (Kiskadee 3), CC BY 2.0, via Flickr

North American vesper bluet damselfly habitats avert cultivation in wet woodlands but not naturalism in Atlantic and Gulf distribution ranges from Nova Scotia through Texas, Nebraska, Colorado, Minnesota, Quebec and everything in-between.
Vesper bluets bear their common names for evening flights and blue colors and the scientific name Enallagma vesperum (together [in ovipositing] damselfly [that flies during] evenings). Common names correlate with scientific committee consensus in the Dragonfly Society of the Americas, whose first Bulletin of American Odonatology issue considered New York state's odonates. Scientific designations defer to descriptions in 1919 by Philip Powell Calvert (Jan. 29, 1871-Aug. 23, 1961), author in 1893 of the model for regional insect study.
Vesper bluet damselfly life cycles expect lakes, ponds, slow stream reaches and slow-flowing rivers with emergent, floating and subsurface vegetation and with nearby or waterside woodlands.

February through November function as maximum, most southerly flight seasons even though June through July furnish wildlife mapping opportunities throughout coastal and inland vesper bluet niches.
Vesper bluet damselflies go to low-lying foraging, patrolling, pre-mating perches on water-lily pads, sometimes by midafternoon, typically after dark, at dusk or one hour before sunset. They head out from hidden roosts in nearby or waterside herbaceous or woody vegetation and hover over open water before hastening back after the early evening. They immobilize flushed or opportunistic, low-flying or low-lying, motionless or moving prey within dark-striped orange-yellow legs and lower lips like gleaning pond damsels, not sallying dancers.
Ants, biting midges, ducks, falcons, fish, flycatchers, frogs, grebes, lizards, robber flies, spiders, turtles and water beetles and mites jeopardize North American vesper bluet damselfly habitats.

Immature vesper bluets keep to pale blue-colored, small sizes even though adults know blacks, blues, yellows as males and blacks, blues, green, oranges, yellows as females.
Incomplete metamorphosis leads vesper bluets from rod-shaped eggs laid in stems just below water surfaces to multi-molting, non-flying larvae, naiads or nymphs and to molted tenerals. Pale blue, shiny-winged, soft-bodied, weak-flying tenerals manage color and sexual maturation before mating for 20 minutes away from water and manipulating eggs into subsurface ovipositing sites. 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 vesper bluet damselfly habitats offer season-coldest temperatures, northward to southward, from minus 45 to 30 degrees Fahrenheit (minus 42.11 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 vesper bluets.
Black abdomens, shoulder and upper thoracic stripes, blue, green, orange or yellow heads, legs, sides, thoraxes and tips and orange-brown yellow eyes quicken adult female identifications. Males reveal bars connecting small eyespots, blue-segmented, pale-ringed, slender, yellow-sided black abdomens, orange-yellow eyes, yellow thoraxes with brown-, narrow-striped midlines and shoulders and yellow-faced black heads. Adults show off 1.14- to 1.46-inch (29- to 37-millimeter) head-body lengths, 0.04- to 1.18-inch (24- to 30-millimeter) abdomens and 0.59- to 0.83-inch (15- to 21-millimeter) hindwings.
Black, blue, brown, green, orange, yellow color combinations and evening matings and ovipositings tell vesper bluets from other damsels in North American vesper bluet damselfly habitats.

vesper bluet (Enallagma vesperum) in teneral state of imago (last stage of metamorphosis); teneral is a pale, soft-body state taking place immediately after moulting; the exoskeleton has not hardened and final coloration has not occurred; Grand River at Glenshire Road, Summit Township, Jackson County, south central Michigan; Aug. 15, 2014: Don Henise (Kiskadee 3), 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:
vesper bluet damselfly (Enallagma vesperum); Grand River at Glenshire Road, Summit Township, Jackson County, south central Michigan; Aug. 15, 2014: Don Henise (Kiskadee 3), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/kiskadee_3/14862291298/
vesper bluet (Enallagma vesperum) in teneral state of imago (last stage of metamorphosis); teneral is a pale, soft-body state taking place immediately after moulting; the teneral's exoskeleton has not hardened and final coloration has not occurred; Grand River at Glenshire Road, Summit Township, Jackson County, south central Michigan; Aug. 15, 2014: Don Henise (Kiskadee 3), CC BY 2.0, via Flickr @ https://www.flickr.com/photos/kiskadee_3/15045833031/

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.
Berger, Cynthia. Dragonflies. Mechanicsburg PA: Stackpole Books: Wild Guide, 2004.
Bright, Ethan. "Enallagma vesperum Calvert, 1919: 380 - Vesper 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. "Gundlach's Work on the Odonata of Cuba: A Critical Study: Enallagma vesperum new species." Transactions of the American Entomological Society, vol. XLV, no. 4 (December 1919): 380-385. Philadelphia PA: The American Entomological Society at The Academy of Natural Sciences, 1919.
Available via Biodiversity Heritage Library @ https://biodiversitylibrary.org/page/7268442
"Enallagma vesperum." 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=3691
Paulson, Dennis. Dragonflies and Damselflies of the East. Princeton NJ: Princeton University Press, Princeton Field Guides, 2011.


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