Somatochlora minor
(Ocellated Emerald)


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

Description:
   Naiad- This is a medium-sized naiad with a length of 13/16 to 15/16 inch (20 to 22 mm). The abdomen is rounded, giving it a short, stocky appearance known as the sprawler form. The color is pale to dark brown, and the sides of the thorax are unmarked. It has small hooks on the tops of abdominal segments four through nine, and 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 2 inches (42 to 50 mm). It is a brilliant metallic green and is marked with several golden yellow spots on the thorax. The upper anal appendages of the males are straight and touch at the tips.

Range:
This species is found from British Columbia east to Nova Scotia, extending south to Washington, Wyoming, and New York. In Idaho, it occurs in the northern half of the state.

Habitat:
This dragonfly can be found near slow, clear streams. In Idaho and eastern Washington, this dragonfly is typically found along slow, willow-lined streams, often with sandy or muddy bottoms.

Adult Flight Season:
Early June to late July

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 debris on stream 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. Adults generally fly from early June through July.

Reproduction:
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.

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 Unpublished M. S. thesis.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.

HTML by Marty Peck, 2001.