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Magical Wings Herald Unique Airlift for Dragonflies
By Tor Hansen, iBerkshires columnist
05:28PM / Sunday, October 06, 2019
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Along the runoff stream at Greylock Reservoir, a male ebony jewelwing will perform an aerial ballet parading near the female. They are widespread from Florida to lower Canada and west beyond the Mississippi River.

A male widow skimmer (Libellula lactuosa) with its chalky blue-white abdomen may at first be confused with common whitetail and a saddlebags dragonflies.

Similar in external appearance, the Northern bluet is the larger with bold blue eyespots and marsh bluet is smaller with small blue eye spots. Like dragonflies their early stage is as a larval nymph confined to life underwater.

A female widow skimmer (Libellula lactuosa) inhabits the Greylock Reservoir and adjacent runoff brook.

A female common whitetail (Libellula lydia) inhabits streams at Mountain Meadow in Williamstown. The female will lay eggs by dipping her abdomen into pond water often guarded by male whitetail.

Male Painted skimmers (Libellula semifasciata) inhabitant well vegetated ponds and sluggish streams at Mountain Meadow.

The Eastern amberwing (Perithemis tenera) is common across New England and one of the smallest. It has an intriguing method of discharging fertile eggs into vegetated ponds.

A male blue and one female green darners are same species (Anax junius ); mating pair post 'a copula' is ova-positing fertile eggs into a pond.

Damselflies are in family Coenagrionidae and within the order Odonata with dragonflies and are so similar that to key out exact species requires astute expertise. Thus this mating pair is within the diverse genus Enallagma. Female is dark overall.



A mating pair of ebony jewelwings will remain coupled for hours in a bizarre configuration with the male attaching behind her head, and female attaching at first abdominal segments instead of conventional distal end.
As a boy of seven years outside in the flower garden teaming with life, I was free to observe the natural wonders of flying insects abounding at assorted flowers including tiger swallowtails, mourning cloaks, silver spotted skippers, and the many bees, paper wasps, from honey bees to hornets and cicada killer giants. Katydids and praying mantis, too.
 
Thanks to incentive provided by my dear parents, Leonard and Eleanor Hansen, my appetite for insect studies was further inspired shortly thereafter by repeated visits to the American Museum of Natural History and the Gilbert Hall of Science in New York City, hence the latter was the source of the beginner's microscope, simple in magnification but adequate to behold the amazing wings of dragonflies. Peering through the magnifying lens of my first microscope, I became captivated by the golden wings of a dead bumblebee. For minutes on end did I remain riveted by the articulate venation and associated membranes drawn so intricately by the chitinous veins. Just for starters of course, that led to studying the  overall anatomy of head, eyes and antennae.
 
Years later I could not help but notice the ingenious structure supporting the art of leaded windows of The Cloisters, also in New York, a superb museum of medieval art and reconstructed here with stone and wood elements from various abbeys and monasteries across Europe. These windows show precise attention to geometric frames linking panes of glass soldered into a uniform window as an outgrowth perhaps from reflections of a monk during the Middle Ages, who first looked seriously at the wonder of dragonfly wings as a source for such intricately designed leaded frames of fascinating stain glass windows adorning many church and home fenestra. 
 
The modern-day composer Ottorino Respeghi created the tone poems "The Birds" and "Church Windows" that reflect his love for nature in musical form, and respect for the artisans who made such wonder works of art that may have been inspired by diverse aerial acrobatics agile on their ample dragonfly wings.
 
Before long at age 8, I was filling empty cigar boxes with insects with orders spanning ants, beetles, to butterflies to wasps. My parents noticed my keen interest in butterflies from those attracted to our burgeoning flower garden in Englewood, N.J. My first butterfly net with green mesh came from a mail order from the American Museum complete with riker mount, display and glass-headed pins and papered specimens. 
 
Examine close up the wing venation of a dragonfly, and one has to be amazed how complex is the structural framework that enables it to glide and zip about, change direction in an instant, and hover over water (like a helicopter dropping freight) so to deposit eggs into a pond. So to create the next generation, a male must attach to a female and fertilize her eggs. Male spermatozoa pass into the female's receptive organ in a most unconventional and bizarre way, gripping his abdomen behind her head! And to be even more incredulous the female attaches to the male near the thorax, not at the distal tip of the expected abdomen. Fertilized eggs (the zygote) may remain incubating inside her for days until eggs are laid underwater in aquatic plants or in the primordial ooze. 
 
They grow into aquatic nymphs and by the process of gradual metamorphosis, shed their exoskeleton skins several times, climb out of the pond onto a pickerel weed, soon to emerge a winged lord of the air.
 
As far back as the Devonian Period, some 340 million to 400 million years ago, insects invaded the dry land, guided by a still mysterious force enabling an aquatic nymph to become a terrestrial flying dragon capable of feeding and reproducing its own species with certain ease.
 
Dragonflies evolved along certain lines quite different from other insects; not even cicadas that show gradual metamorphosis similarities, i.e. nymph to adult, bypassing the chrysalis and pupal stage, show this bizarre mating pattern. A good place to start is to acknowledge mutation in gene pooling may govern tissue and cellular changes that reroute reproductive organs and thus produce the instinctual and behavioral adjustments.
 
Here on Mount Greylock in our Berkshires I have located an enclave of spritely ebony jewelwings that with the afternoon slanting sunlight are busily living up to every bit of their zest in mating courtship. No doubt true courtship as we know it in higher vertebrates may be ritualized. About eight individual jewel wings are involved in mate selection, and adding live observation wants to add to the literature in wikipedia. Walking the grassy service road beside a babbling brook, created by the spillway from the Greylock Reservoir above, some time can pass before I see any activity, as these jeweled damselflies rest on stream side jewelweed, grasses or JoePye Weed growing lush from the shallow streambed itself.
 

A female ebony jewelwing with white wing dot will attract several males to initiate mate selection.
As the dappled sunlight dances over the green foliage single males and females take up adjacent roosting. The male may hover close to the female and entrance her with his shadowy wings beating like outstretched fans. If she appears to stretch her wings, he initiates "a copula." Additional males may appear and try to interrupt their ephemeral ballet, but usually the original male prevails. However The female may remove his eggs prior to mating with another male jewelwing. Spermatozoa can be stored, and fertilization may not be completed until just before eggs are laid underwater in aquatic plants. However strange their copulation may appear, their configuration has stood the test of time.
 
As simplified, evolution up through the tower of time may read "change through time." Dragonflies appear in the limestone fossil record at Solnhofen, Germany, as late as upper Jurassic period, perhaps 150 million years ago. But perhaps they diversified much earlier prior to the Devonian period in the Silurian times. They flourished in ancient lagoons and marshes.
 
Likely jewelwings evolved later from a central stock. Just when remains an educated guess when a fossil hunter uncovers more recent dragonflies preserved by mineral replacement, and correct age of the strata is confirmed by carbon 14 and barium analysis.
 
A real thought teaser arises when we question just how do ebony jewelwings, eggs, larvae, or adults survive significant drought, as evidenced by very recent longs days without any rains, right here at the same bone dry brook, no longer babbling. Perhaps this mystery can be solved by intricate search among the streambed stones where moisture beneath may protect the eggs laying dormant until new rains replenish the water column in the reservoir, as autumn leaves swirl down into the brook once again doused by a passing rain shower.
 
Tor Hansen is a naturalist writer, photographer, and musician, in North County.

 

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