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Aeshna interrupta
Variable Darner
Family: Aeshnidae
Species account author: Robert Cannings.
Extracted from Introducing the Dragonflies of British Columbia and the Yukon (2002)

Photograph

© Jeremy Gatten     (Photo ID #5914)

Map

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Distribution of Aeshna interrupta in British Columbia.
(Click on the map to view a larger version.)
Source: (for the static map) RBCM and BCCDC 2004 ©

Species Information


Description

The scientific name comes from the distinctly broken thorax stripes, usually on males found on B.C.’s coast; interior populations normally have complete narrow stripes. This variation gives the species its English name. The stripes are usually yellow-green below and blue above. The face is green-yellow to pale blue with a black line. Pale areas on females are usually green or yellow, but some are blue. Male’s appendages simple. Length: ♂ 70 mm, ♀ 66 mm.


Flight Period

B.C., late May (though uncommon before July) to early November; Yukon, late June to early September.

Genus Description


Mosaic Darners are common in B.C. and the Yukon; they fly everywhere dragonflies are found. All 11 B.C. species are large and can usually be distinguished by their variations on a basic colour pattern. Generally, the body is brown, and each side of the thorax has a pair of blue, green or yellow stripes – their shape is important in identification. Look also for the colour of the face and the line across its middle. Viewed from above, the forehead bears a distinctive T-shaped mark, called the “T-spot”. The abdominal spots on males are usually blue, and on females green, yellow or blue. Male upper appendages come in three types.

Biology

Family Description

Large, swift-flying dragonflies, usually marked with blue, green or yellow. Adults hunt tirelessly for insects over ponds, lakes and streams, and wander widely in search of prey. Most species rest in a vertical position, but a few sit flat on the ground. Females have a prominent ovipositor and lay eggs in water plants or floating wood above or below the water line. Larvae are slender and sleek, with flat labia lacking bristles; they are rapacious hunters among water plants. Recently, A. californica and A. multicolor have been transferred from Aeshna to Rhionaeschna.
Field Notes

Common in B.C. and southern Yukon valleys; rare in the Porcupine basin. Lives in many habitats from northern and mountain peatlands to cattail marshes and temporary pools. It is the characteristic darner of grassland ponds.

Distribution


Northern. Widespread throughout B.C. and to the Porcupine River drainage in the Yukon.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
NativeS5YellowNot Listed



BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.