Plathemis lydia

(Drury, 1773)

Common Whitetail, Long-tailed Skimmer

Plathemis lydia, commonly known as the Common Whitetail or Long-tailed Skimmer, is a widespread across North America. The species exhibits striking : males possess a conspicuous white and brownish-black wing bands, while females have a brown body with different wing spot patterns. Research has documented significant wing morphometric differences between sexes, with males showing adaptations for faster and higher acceleration capacity, likely related to territorial and evasion. The species inhabits a variety of freshwater and is among the most frequently observed dragonflies in North America with over 110,000 iNaturalist records.

Plathemis lydia by (c) Michael J. Papay, some rights reserved (CC BY), uploaded by Michael J. Papay. Used under a CC-BY license.

Plathemis lydia by the Smithsonian. Used under a CC0 license.

Pronunciation

How to pronounce Plathemis lydia: //pləˈθiːmɪs ˈlɪdiə//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Males distinguished by white and checkered wing pattern; females resemble female Libellula pulchella (twelve-spotted skimmer) but can be separated by wing spot details. The combination of white abdomen (males) or brown body (females) with banded wings separates this from most sympatric skimmers. Wing morphometrics can distinguish sexes: males have relatively shorter, narrower-based hind wings with pointier tips and higher wing loading.

Images

Appearance

Males have a chunky white approximately 5 cm long, combined with brownish-black bands on otherwise translucent wings creating a checkered appearance. Females have a brown body with a different pattern of wing spots. Both sexes display 'pinstripes' on the . Male hind wings are narrower at the base and middle with pointier tips compared to females. Total body length ranges 38-45 mm with hind wing length averaging 30-35 mm.

Habitat

Freshwater including ponds, slow-moving streams, and rivers. One study site in Greenville, North Carolina involved public lands with accessible water bodies. The shows adaptability to various aquatic environments across its broad range.

Distribution

Widespread across much of North America; present in Middle America and North America including Vermont and throughout the United States. The is one of the most commonly encountered in North America based on observation frequency.

Seasonality

Active during summer months; field studies conducted during summer 2022 confirm activity in June-July period. Specific varies across the broad geographic range.

Life Cycle

Aquatic nymph stage with developed tracheal ; nymphs inhabit freshwater environments. emerge and are terrestrial/aerial. Specific details on laying, nymph development duration, and timing not documented in available sources.

Behavior

Males engage in territorial chases with other males, using their conspicuous white in these interactions but not during courtship with females. Males exhibit variable mate-guarding as a reproductive strategy, showing behavioral plasticity in mating tactics. performance differs between sexes: males are adapted for speed and agility (higher acceleration capacity), females for maneuverability. Males are more conspicuous to than females due to white coloration.

Similar Taxa

Libellula pulchellaFemale Plathemis lydia closely resembles female twelve-spotted skimmer in wing spot pattern; requires careful examination of spot details for separation
Pseudoleon superbusBoth are skimmers with banded wings; Filigree Skimmer has more extensive black on wings especially in males, more reticulated pattern in females, and is subtropical in distribution
Plathemis subornataDesert Whitetail is a congeneric with similar male white but differs in distribution and preferences

More Details

Wing Morphometrics Research

A 2024 study documented significant in wing : males have 18% shorter fore wings and 15% shorter hind wings relative to body size, with 20% lower wing area and 25% higher wing loading. These traits correlate with faster and higher acceleration capacity in males, advantageous for territorial chases and evasion.

Research History

Early anatomical work in 1916 described the tracheal distribution in nymphs. Behavioral studies since 1987 have examined variable mate-guarding tactics. Recent morphometric research (2024) has quantified adaptations linked to and territoriality.