Libellula (Plathemis) lydia
(Common Whitetail)


Order: Odonata
Suborder: Anisoptera
Order Description:
Dragonflies
Family: Libellulidae
Family Description: Whitetail

Description:
   Naiad- This is a medium-sized naiad with a length of 7/8 to 15/16 inch (21 to 24 mm). The abdomen is rounded, giving it a short, stocky appearance known as the sprawler form. There is a single, curved, sharply pointed hook on the tops of abdominal segments two through six, the tallest of which occurs on segment five. Additionally, there is a single, rear-facing spine on each side of abdominal segments eight and nine.
   Adult- This is a medium-sized dragonfly with a length of 1 11/16 to 1 7/8 inches (42 to 48 mm). The abdomen appears broad. Mature males have partially clear wings, with the central third portion of each wing marked with a large dark patch and a small dark spot at each wing base. The top and sides of the abdomen are pruinose white, with the white extending onto each hindwing along the bottom edge of the dark spot. The thorax may have several lines or spots of yellow. In females and immature males, each wing has a small dark patch at the base, at the center, and at each tip (the patch at the tip may be more yellowish). The thorax and abdomen is brown marked with yellow.

Range:
This species is found through most of the U. S. except for the desert Southwest, where it is replaced by the Desert Whitetail, Libellula subornata. In Idaho, it can be found throughout the state at lower elevations.

Habitat:
This dragonfly can be found near weedy, warm-water ponds and lakes.

Adult Flight Season:
Mid-June to late August

Diet:
   Naiad- Naiads feed on a wide variety of aquatic insects, such as mosquito larvae, other aquatic fly larvae, mayfly larvae, and freshwater shrimp. They will also eat small fish and tadpoles.
   Adult- The dragonfly will eat almost any soft-bodied flying insect including mosquitoes, flies, butterflies, moths, mayflies, and flying ants or termites.

Ecology:
The naiads live in submerged aquatic grasses and sedges. They do not actively pursue prey but wait for it to pass by, a strategy which affords them protection from other predators. Naiads emerge as adults at night. Adults generally fly from mid-June through most of August. This species is most abundant in late spring and early summer. The adults hunt from perches on vegetation. The white abdomen and wings patterned with black make it a very striking dragonfly.

Reproduction:
Males establish and defend territories at choice breeding locations. After males and females mate, the female flies singly, without the male attached, to lay her eggs. She doe this by dipping the tip of her abdomen along the weedy margins of lakes and ponds while hovering just above the water's surface.

Conservation:
Populations are widespread, abundant, and secure.
Status: Unprotected nongame species
Global Rank: G5
State Rank: S?

References:
Corbet, P. S. 1999. Dragonflies: Behavior and Ecology of Odonata. Cornell University Press, Ithaca, New York, USA, 829pp.

Logan, E. R. 1967. The Odonata of Idaho. Unpublished M. S. thesis. University of Idaho, Moscow, Idaho, USA, 105 pp.

Needham, J. G. and M. J. Westfall. 1955. Dragonflies of North America. University of California Press, Berkely, California, USA, 615 pp.

Paulson, D. R. 1999. Dragonflies of Washington. Seattle Audubon Society, Seattle, Washington, USA, 32 pp.

Walker, E. M. and P. S. Corbet. 1975. The Odonata of Canada and Alaska, Vol. III. University of Toronto Press, Toronto, Ontario, Canada, 307 pp.


Written by Mark Lung and Stefan Sommer, 2001
Photos by Dennis Paulson, 2001
Design by Ean Harker, 2001.