Dragonfly or Damselfly?

About 5,000 species of odonata — the insect order that includes both dragonflies and damselflies — exist in the world. Michigan has 162 different species. Though the majority are found in the southern part of the state, Northern Michigan is still a hot spot for sighting them; its range of habitat — we’ve got forest, lakes, dunes, interdunal ponds, bays, rivers, bogs, fens and springs galore — and tip-of-the-mitt flyway position makes for major dragonfly and damselfly diversity.

Dragon or Damsel? Dragonflies tend to be bigger, bolder and more daring in their acrobatics than the more slender and skittish damselflies, but the easiest way to tell the two apart is by watching them at rest: a dragonfly’s wings will lie flat, at right angles to its body; a damselfly can hold its wings together or spread in a slight V shape.

Mating Ritual: If you see a pair of dragonflies linked together in midair, you’re privy to some not-so-private procreation. Called the copulation wheel, the mating act works like this: The male grabs the female’s head with his end appendage, a hook called “the clasper.” Like a lock to a key, notches and grooves in the female’s head and the male’s clasper fit precisely, ensuring each sex mates only with its own species. The female then curls her abdomen under her, reaching forward with the tip of her abdomen to pick up the sperm from the males second set of genitals (yes, they have two) under his abdomen. Damselflies do it much the same way, though they most often complete the copulation on vegetation, sometimes flying together in tandem until they find a suitable site. The shape the pair makes when linked like this resembles a heart; some believe it is the original source of the heart’s symbolic meaning for love.

Operation Egg Drop: Post-copulation, some males will stick around, guarding the female to ensure she lays the eggs fertilized with his sperm. (If a new male comes along before she has oviposited, he has the ability to scrape away her already fertilized eggs, then fertilize a new bunch himself.)

Other males will go so far as to remain attached until she has laid at least some eggs. Depending on the species, the female may insert individual eggs into vegetation — dead wood or reeds perhaps — or drop them into the water. Sometimes the pair will dive into the water — the fine hairs on their body create a protective coating of air that enables them to breathe — to deposit the eggs below the waterline.

Lynda Twardorski is assistant editor of Traverse, Northern Michigan’s Magazine. [email protected]

Note: This article was first published in June 2006 and was updated for the web February 2008.

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