Common Whitetail

Plathemis lydia — the common whitetail — is one of the most widespread and most-recognized dragonflies in North America and one of the most striking examples of gender dichromatism in North American Odonata. The species is widespread across all of North America from southern Canada south through the eastern US to Mexico, and is one of the most common dragonflies at pond margins, lake shores, and slow streams. Adults are 4-5 cm body length, 6-7 cm wingspan. Adult males have a striking CHALKY-WHITE ABDOMEN (the source of the common name — the white coloration is created by waxy pruinescence that develops gradually over the first 1-2 weeks of adult male life), framed by broad BLACK WING BANDS at the middle of each wing (a wide brown-to-black band on each forewing and hindwing). Females have a completely different appearance — brown-and-yellow striped abdomen, with each wing marked with THREE WHITE PATCHES (a basal patch, a middle patch, and a tip patch). The female pattern superficially resembles the twelve-spotted skimmer (Libellula pulchella) and is a common source of misidentification. The dramatic gender dichromatism makes male and female whitetails look like completely different species — a common cause of confusion among casual dragonfly observers. The species' identifying behavior is the WHITE-ABDOMEN TERRITORIAL DISPLAY: mature males perch on prominent pond-margin substrates (rocks, twigs, exposed soil) and FLICK THE WHITE ABDOMEN UP AND DOWN at rival males, with the white pruinescent surface flashing against the dark wing bands and dark surroundings. The display signals territory ownership and quality to passing females. Common whitetails are major beneficial mosquito predators — adults consume hundreds of mosquitoes per day, and naiads consume mosquito larvae and other aquatic invertebrates over a 2-3 year aquatic development period. The species is one of the most widespread dragonflies in North America and one of the most-photographed in NA macro nature photography because of the dramatic visual contrast of the white abdomen against the dark wing bands.