Dragonflies…On the Fly
Checkered Setwing (Male, Red-faced) All photos by Eva Frost
In October, 2018, we published our first online edition of The Hays Humm. Our feature article that month was Dragonflies…On the Fly by Master Naturalist Eva Frost. Eva’s scientific summary and photo-rich content about dragonflies set a high bar for us. We’ve learned a lot about website publishing over the last four years, and with a few minor edits and extra photos, here is her article again. I hope you enjoy it as much as I do.
—Betsy Cross, Hays Humm Editorial Team
Eva Frost, Hays County Master Naturalist
Checkered Setwing (Female)
Dragonflies were the first winged insect to evolve 300 million years ago. Their four wings are 2-5 inches long now, but back then, they were 2-4 feet long. Meganeura, a genus of extinct insects from the Carboniferous Era, was the largest insect known. It is believed that the high oxygen levels in the Paleozoic, until the end of the Permian Era, attributed to their large size.
Dragonflies evolved from this creature. Some nicknames for dragonflies include snake doctor, devil's darning needle, spindle, ear sewer, and my favorite, the skeeter hawk.
Females leave eggs in waterways or swampy waters. Even if she dies, her eggs will still survive, hatch in the water, and become predators of anything they can eat. They are called naiads. They have a voracious appetite and will even eat small fish and other naiads. They do this for about a year or two.
They shed a few times before the larvae, or naiads, climb up on a stick and shed their exoskeleton. This could happen quickly…
...or it could take an hour or longer. You can usually find little exoskeletons going up the sticks in the water.
Then the new "teneral" dragonfly hangs sometimes for another hour or longer. This is a time for "pumping up," leaving them in a very vulnerable state. Some adults live a few weeks, some a few years.
Amberwing with exoskeletons at the launch pole.
Dragonflies have to reach a temperature of 63 degrees to get moving. And these voracious eaters can only eat when they are flying, which they are extremely good at. They literally consume everything, including other dragonflies. On a good note, one dragonfly can put away 30 to hundreds of mosquitoes in a day. They have a small "arm" hanging beside their mouth to assist in holding the prey or cleaning the face.
Its head is all eyes, and they have 360-degree vision, which begs the question, "Why are they always flipping their head back and forth?" Actually, a dragonfly can pick one individual flying insect from a group of flying insects and calculate its speed and trajectory to catch that exact fly. So, I guess it's doing math!
Four-spotted Pennant - obelisking
Hundreds of different species will gather for feeding or migrating in the early morning on a freshly mown wet yard or near a swampy area or water catchment. They do like it hot too, so in the afternoon, they are found perched at the tip of bare sticks or the points of a century plant. Agaritas, Red Yuccas, and the tops of trees are good perches. They regulate their body temperature by abdomen obelisking.
Dragonflies and damselflies are in the Order Odonata, from the Greek meaning "the toothed one." Dragonflies are in the infraorder Anisoptera. The damselfly is from the Zygoptera. You can tell them apart, because the damselflies are smaller and sit with wings folded up. They seem to have two large separate eyes. Damselflies will also sit on a rock or a stick for a while, as dragonflies are more on the move. Their presence is the sign of a healthy ecosystem and clean waters!
Blue Duet (damselflies)
More Interesting Facts
The Halloween Pennant (shown here) is the butterfly of the dragonflies.
Dragonflies are a snack in Indonesia.
Some Indians revere them as gods, as others believe they are Satan or bad luck.
The Globe Skimmer has the longest migration of any insect - 11,000 miles back and forth across the Indian Ocean.
When mating, a male can only place his "pincers" on a female of the same species.
Males can remove the sperm of previous dragonflies before mating.
The incredible flying skills of the dragonfly are being studied and applied to robots and other aero-dynamic applications.
The wing venation in the sunlight makes them light up.
Dragonflies and damselflies are a sign of a good habitat and great water quality!
A Slideshow from Eva’s Dragonfly Collection
THE MASTER NATURALIST LOGO
Excerpt from information about the Texas Master Naturalist Logo by Michelle Haggerty
When the [Texas Master Naturalist] program was implemented statewide in 1998 we chose the Cyrano Darner as the program logo from several other species drawings which are also represented in the program today.
At the time, we wanted a logo that wouldn’t be confused with those of other nature organizations and since dragonflies were not yet seen very often in logos—unlike oak leaves, horned lizards, bluebonnets and other emblems of Texas flora and fauna—we chose it. Of course dragonflies are everywhere now, but who knew?!?