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Catch the buzz about one of Ohio's most primitive insects
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Above, American Rubyspot.
Below, White-faced Meadowhawk. |
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Spend a summer day around most any Ohio waterway and you're likely to get "buzzed" – by a dragonfly that is – one of the most fascinating and ancient creatures on earth.
Well-known for their aerial acrobatics, dragonflies have been buzzing about for more than 250 million years. They belong to an "old order" of insects known as Odonata, which also includes damselflies.
Dragonflies and damselflies (odonates) display an array of eye-catching colors and patterns, including metallic blues, greens, bronzes and reds. Sunny summer days are particularly good times to spot these jewel-toned insects, as they hover over streams and ponds, cling to creek-side rocks and reeds, or flit across open meadows.
Worldwide there are more than 5,000 species of odonates. A study published in 2002 reported 162 of those species have been spotted here in Ohio. And, of that number, about 40 percent are considered to be common to our state.
Many of these insects have intriguing names that reflect their festive colorations, such as mocha emerald (dragonfly), American rubyspot (damselfly), and Halloween pennant (dragonfly).
All odonates share similar traits:
- large heads dominated by over-sized eyes;
- slender, elongated bodies; and
- two pairs of transparent wings.
During the "days of the dinosaurs," dragonflies and damselflies were not much different from the ones we see today, except that they were many times larger. Fossil remains reveal that some odonates had an amazing 2-foot-plus wingspan. Fortunately for Ohioans, and their windshields, the average Buckeye State odonate has a wingspan of about 2 inches.
The heavily veined wings of dragonflies and damselflies usually beat out of sequence, while the front pair is moving up, the hind wings move down. And, because of the way they are attached, each wing can be moved independently, allowing for extreme maneuverability.
Such attributes allow these artful dodgers to make abrupt stops, sharp turns and even fly backward. Experts estimate that some dragonflies can achieve bursts of speeds of 30 mph or more.
But, as in all families, there are differences.
The dragonfly is the huskier of the two, and the one that tends to race from place to place. By comparison, damselflies are dainty, flying through life at a more relaxed pace. A good way to tell them apart is by observing the wing position when they are at rest. The wings of a dragonfly remain straight out, like those of an airplane, while a damselfly holds its wings over its body.
It's also the wings that place both of these species apart from "modern-day" insects. Flies, mosquitoes and bees, for example, can both fold and lay their wings down on their bodies.
Odonates are meat eaters, dining on insects such as mosquitoes, gnats, flies and even butterflies. They hunt prey entirely by sight, which is why they have such large, compound eyes. It's believed each eye contains more than 28,000 lenses.
Even though they fly as adults, biologists consider dragonflies to be aquatic insects. This is because they live near water, and young odonates – known as nymphs – actually live in the water. In fact, because their lives are so intertwined with water, these beautiful winged creatures are excellent barometers of a healthy waterway.
Just as with birding, interest in dragonfly watching and photography is growing across the country. So, grab your binoculars and a camera this summer then head to the nearest waterway - it's sure to be buzzing with activity!
For more information, contact:
Laura Jones, ODNR Communications
614-265-6811