Somatochlora albicincta
(White-ringed Emerald)

Order: Odonata
Suborder: Anisoptera
Order Description:
Family: Corduliidae
Family Description: Emerald

   Naiad- This is a medium-sized naiad with a length of 13/16 to 1 inch (20 to 23.5 mm). The abdomen is rounded, giving it a short, stocky appearance known as the sprawler form. The color is uniform brown, and the sides of the thorax are unmarked. 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 3/4 to 2 1/16 inches (45 to 52 mm). It is a brilliant metallic green, with each side of the thorax marked with several wavy yellowish stripes or dashes. Each abdominal segment is ringed with yellowish white where it joins with the following segment. The eyes are bright green.

This species is found from Alaska east across Canada to Labrador, extending south to Washington and New Hampshire. In Idaho, it has been documented to occur only at the Roman Nose lakes in Boundary County, but it probably occurs in the mountains of the northern and central portions of the state.

This dragonfly can be found near mountain lakes.

Adult Flight Season:
Late June to September

   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.

The naiads live in submerged vegetation and woody debris on lake bottoms. They do not actively pursue prey but wait for it to pass by, a strategy which affords them protection from other predators. Naiads may require several years to mature, and typically emerge as adults at night. Although records are sparse, adults are believed to fly from late June to September.

The males establish and defend territories along the shores of mountain lakes, and actively patrol them in search of receptive females. Males on patrol can be very aggressive and will chase dragonfly species much larger than themselves. After males and females mate, the female flies singly, without the male attached, to lay her eggs by dipping the tip of her abdomen on the surface of the water while hovering above it.

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

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.

HTML by Marty Peck, 2001.