Delta-Spotted Spiketail Dragonfly Habitats: Paired Yellow Triangles

Summary: North American delta-spotted spiketail dragonfly habitats get black bodies with green eyes barely touching and paired yellow stripes and triangles.

delta-spotted spiketail dragonfly (Cordulegaster diastatops); Lost Land Run, Garrett County, westernmost Maryland; Saturday, June 18, 2016, 10:55: Judy Gallagher, CC BY 2.0 Generic, via Wikimedia Commons

North American delta-spotted spiketail dragonfly habitats avoid cultivation near boggy seeps but not naturalism in distribution ranges from Nova Scotia through Ontario and Wisconsin, through Virginia, Ohio and Michigan and everywhere in-between.

Delta-spotted spiketails bear their common name for triangle-patterned abdomens and for the females' spiked ovipositors and the scientific name Cordulegaster diastatops (club-shaped belly [and] separated eyes). Common names consolidate the consensus of scientific committees convened by the Dragonfly Society of the Americas, whose second Bulletin of American Odonatology considers Floridian odonate distributions. Descriptions in 1854 by Michel Edmond de Sélys Longchamps (May 23, 1813-Dec. 11, 1900), Chambre de Représentants (Chamber of Representatives) member-elect from Waremme, drive scientific designations.

Delta-spotted spiketail dragonfly life cycles expect small streams and sunny seeps with boggy spring runs and skunk cabbage in open or wooded glens and powerline corridors.

April through August function as earliest to latest flight seasons even though June and July furnish wildlife mapping opportunities for all coastal and inland delta-spotted niches.

Male delta-spotted spiketails go from night-time resting roosts to daytime foraging patrolling, pre-mating perches on weedy stems and twigs near sunlit forest edges and sunny clearings. They hang at angles of 45 degrees to daytime perches before and subsequent to heading downstream and upstream and hovering low over mossy and open waters. Hunting for invertebrate prey to imprison within clawed, dark, three-segmented legs and powerful lower lips and patrolling for mates inspire intensive investigations during 2-plus-yard (1.83-plus-meter) itineraries.

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

Immature delta-spotted spiketail dragonflies keep dull, faded, light, pale colors on small bodies whereas adult females and males know bright black, green, white and yellow colors.

Incomplete metamorphosis links rod-shaped eggs laid by upright females' sewing machine-like, up-and-down abdominal motions above floating moss, multi-molting, nonflying larvae, naiads or nymphs and molted tenerals. Shiny-winged, soft-bodied, weak-flying tenerals mature physically and sexually away from molting places before moving back for mating and for ovipositing in shallow pools, seeps and streams. Spiketail members in the Cordulegastridae (club-bellied) dragonfly family need aphids, beetles, borers, caddisflies, copepods, crane flies, dobsonflies, gnats, leafhoppers, mosquitoes, rotifers, scuds, water fleas and worms.

North American delta-spotted spiketail dragonfly habitats offer season-coldest temperatures, north- to south-ward, from minus 45 to 0 degrees Fahrenheit (minus 42.11 to minus 17.77 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 delta-spotted spiketails.

Black, thick abdomens with protruding ovipositors and yellow backward-pointing triangles and side-stripes, black-crossbanded white faces, sea-green eyes and yellow-striped black thoraxes qualify as adult female hallmarks. Adult males reveal bright green eyes reunited at one point and yellow foreheads on bodies that otherwise resemble females whose abdomens remain thicker, unclubbed and yellower. Adults show off 2.32- to 2.56-inch (59- to 65-millimeter) head-body lengths, 1.65- to 1.93-inch (42- to 49-millimeter) abdomens and 1.42- to 1.65-inch (36- to 42-millimeter) hindwings.

Black bodies, green eyes briefly touching and yellow abdominal triangles and thoracic stripes tell delta-spotted spiketails from other odonates in North American delta-spotted spiketail dragonfly habitats.

delta-spotted spiketail dragonfly (Cordulegaster diastatops); Rivière-du-Loup, southeastern Quebec, eastern Canada; Monday, July 6, 2015, 17:20: André-Philippe Drapeau Picard, Public Domain (CC0 1.0), via Wikimedia Commons

Acknowledgment

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

Image credits:

delta-spotted spiketail dragonfly (Cordulegaster diastatops); Lost Land Run, Garrett County, westernmost Maryland; Saturday, June 18, 2016, 10:55: Judy Gallagher, CC BY 2.0 Generic, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Delta-spotted_Spiketail_-_Cordulegaster_diastatops,_Lost_Land_Run,_Garrett_County,_Maryland_-_28070381856.jpg; Judy Gallagher (Judy Gallagher), CC BY 2.0 Generic, via Flickr @ https://www.flickr.com/photos/52450054@N04/28070381856/

delta-spotted spiketail dragonfly (Cordulegaster diastatops); Rivière-du-Loup, southeastern Quebec, eastern Canada; Monday, July 6, 2015, 17:20: André-Philippe Drapeau Picard, Public Domain (CC0 1.0), via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Cordulegaster_diastatops.JPG

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