Slender Bluet Damselfly Habitats: Big Eyespots, Pale Blue, Thin Stripe

Summary: North American slender bluet damselfly habitats in southeastern Canada and the eastern United States get big eyespots, occipital bars and thin stripes.

a pair of slender bluet damselflies (Enallagma traviatum), with male (above) and female (below); a distinctive field marker is the blueness of the head's postocular, dumbbell-shaped spot, with the male's dark blue and the female's light blue; Jackson Miles Abbott Wetlands Refuge (JMAWR), Fort Belvoir, Fairfax County, Northern Virginia; June 14, 2016: Walter Sanford @Geodialist via Twitter Oct. 24, 2016

North American slender bluet damselfly habitats affix cultivation along clean water and naturalists within distribution ranges from Maine through Florida, Texas, Nebraska, Missouri, Wisconsin, Michigan and New Hampshire and into Ontario, Canada.

Slender bluets bear their common name for slim, trim abdomens and blue colors and the scientific name Enallagma traviatum (together [in ovipositing] damselfly) for two subspecies. The eastern nominate subspecies carries the scientific name Enallagma traviatum traviatum from descriptions in 1876 by Michel Edmond de Sélys Longchamps (May 25, 1813-Dec. 11, 1900). Binghamton University Geology Professor Thomas W. Donnelly's descriptions in 1964 dedicate Enallagma traviatum westfalli to Florida-based entomologist Minter Jackson Westfall, Jr. (Jan. 28, 1916-July 20, 2003).

Slender bluet damselfly life cycles expect permanent lakes and ponds with abundant or sparse emergent, floating, submergent and waterside vegetation and with open or vegetated waters.

April through October function as maximum, most southerly flight seasons even though May or June furnishes wildlife mapping opportunities in all Canadian and United States niches.

Slender bluet subspecies get one geography east of the Alleghenies and the Appalachians and of the southern Mississippi River and another west of the mountain chains. They have the same behavior of hovering over open water and of hunkering amid low-level, waterside vegetation and the same anatomy excluding the westerner's thicker claspers. Both subspecies imprison low-flying, low-lying passersby within projectable, retractable lower lips and three-segmented legs like pond damsels involved in gleaning hunter lifestyles and unlike sallying dancers.

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

Immature slender bluets keep dull, faded, light, pale-colored small sizes even though mature females and males know respectively blue-green with black-brown and blue with black-colored forms.

Incomplete metamorphosis leads from rod-shaped eggs laid in emergent or submerged vegetation to immature, little adult-like, multi-molting, non-flying larvae, naiads or nymphs and to molted tenerals. Shiny-winged, soft-bodied, weak-flying tenerals manage colors and sexual maturation within three weeks, mate over one long session or several short and manipulate eggs into 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 slender bluet damselfly habitats offer season-coldest temperatures, northward to southward, from minus 15 to 20 degrees Fahrenheit (minus 26.11 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 slender bluets.

Blue-banded, blue-ringed, blue-sided, blue-tipped black abdomens, blue-green thoraxes with brown-black shoulder and upper stripes, blue-green-tan, fine-striped eyes, clear wings and large eyespots qualify as female hallmarks. Adult males reveal black-lined, blue-, blue-green eyes and large eyespots with connecting bars, blue-sided, buoy-patterned black abdomens and blue thoraxes with thin-striped shoulders and tops. Adults show off 1.14- to 1.26-inch (29- to 32-millimeter) head-body lengths, 0.95- to 1.02-inch (24- to 26-millimeter) abdomens and 0.59- to 0.75-inch (15- to 19-millimeter) hindwings.

Large eyespots, occipital bars, pale blue colors and thin-striped shoulders tell slender bluets from other bluets and pond damsels in North American slender bluet damselfly habitats.

The first sighting of Westfall's slender bluet (Enallagma traviatum westfalli), one of two slender bluet subspecies, in Canada happened in July 1991 in Southwestern Ontario's Pinery Provincial Park: Jason King ‏@jasonjdking via Twitter Nov. 11, 2017

Acknowledgment

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

Image credits:

a pair of slender bluet damselflies (Enallagma traviatum), with male (above) and female (below): Jackson Miles Abbott Wetlands Refuge (JMAWR), Fort Belvoir, Fairfax County, Northern Virginia; June 14, 2016: Walter Sanford @Geodialist via Twitter Oct. 24, 2016, @ https://twitter.com/Geodialist/status/790479133847326720

The first sighting of Westfall's slender bluet (Enallagma traviatum westfalli), one of two slender bluet subspecies, in Canada happened in July 1991 in Southwestern Ontario's Pinery Provincial Park: Jason King ‏@jasonjdking via Twitter Nov. 11, 2017, @ https://twitter.com/jasonjdking/status/929356505358524417

For further information:

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Available @ https://twitter.com/jasonjdking/status/929356505358524417

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Available via HathiTrust @ https://hdl.handle.net/2027/hvd.32044093256832?urlappend=%3Bseq=541

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Available @ https://twitter.com/Geodialist/status/790479133847326720