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Crawlies with Cri: Common Whitetail Dragonfly (Plathemis lydia)

This week’s crawly is big, bold and beautiful. Meet the common whitetail dragonfly (Plathemis lydia).
Whitetails are in the skimmer Family (Libellulidae). Skimmers earned their common name from the females who skim over the water to deposit eggs.
The “whitetail” name comes from the males who, as you can see, do have white tails. They are dark brown when they hatch and turn white fairly quickly as they age. The white pruinescence is formed by a waxy substance they create.
Females don’t get this waxy glow but remain dark brown and have three spots on each wing versus the males who have only one large black spot on each wing. Between the two, the males are easier to identify as the females look quite like some other dragonfly species.
If you hang out around ponds, lakes or slow-moving streams this summer, you have a good chance of spotting a whitetail. First, they are large, with bodies that are one and three-quarter inches and wingspans of one and one quarter inches. Second, they like to perch near water, then zip out to grab a meal, then perch again to eat.
Common whitetails have also adapted to suburban and urban living, parking lot hunting around puddles, storm drains and culverts, drainage ditches and urban canals.
They’ll use their legs to grab flying insects then perch and munch down with their serrated mandibles. Those chompers give the dragonfly Order its name. Dragonflies are in the Order Odonata, which means “toothed one” in Greek.
That said, dragonflies don’t go around chomping on people. While one might take a nip in self defense, their teeth, while great for munching insects, aren’t strong enough to break people’s skin.
Female whitetails may lay up to 1,000 eggs while skimming over a pond, lake or stream. Once those eggs hatch, whitetail nymphs immediately become a mosquito’s worst enemy as they voraciously chow down on mozzie larvae. Nymphs may take up to two years to mature and will eat a lot of mosquitoes and other aquatic arthropods during that time.
Adults dine on adult mosquitoes as well. Between nymphs and adults, whitetails will eliminate 100+ mosquitoes per day.
Though male whitetails do prefer to lounge in the sun most of the day, they are quite territorial and will patrol their 500 sq. ft. patch periodically and defend it against other male whitetails and other dragonfly species.
While in flight, males will raise their white tails as a warning sign. If the interloper doesn’t back down, the males will attack. While whitetails can live for up to three months as adults, many males don’t make it more than a week because of their propensity for fighting. They often kill each other.
The males are so territorial, they have developed special fight muscles for their skirmishes. Generally, the fights will be centered more around females than territory or available food, so females are the pacifists of the whitetail world.
Whitetails will be on the wing until at least the end of August, so be on the lookout for those bright white tails as you enjoy the outdoors once the weather cools a bit.