E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

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

Photo of species

© Jamie Fenneman  Email the photographer   (Photo ID #4369)

E-Fauna BC Static Map
Distribution of Aeshna umbrosa in British Columbia
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Species Information


Description

Similar to the Paddle-tailed Darner, but darker and more slender. Thorax stripes are yellow to green, often blue above and outlined with dark brown; shape shown in figure. The face is pale green with a pale brown line or no line; the rear of the head is partly pale. Spots on top of the abdominal segments are green or blue; segment 10 is usually black on top. The underside of the abdomen has pale blue spots. The pale areas on females are green, yellow or, rarely, blue. Male’s upper appendages flattened. Length: ♂ 70 mm, ♀ 68 mm.


Flight Period

B.C., mid June to mid November.

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

More common in the south; rare in the southern Yukon. Partial to forest lakes and slow-moving streams; as its name suggests, it likes shady habitats. Often found alongside the Paddle-tailed Darner, its close and usually more common relative. The Shadow Darner is one of the latest flying species in B.C., especially in the south.

Distribution


Transition. Widespread in B.C. and the southern 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.

Additional Photo Sources

General References


Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2021. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2021-10-18 7:55:27 PM]
Disclaimer: The information contained in an E-Fauna BC atlas pages is derived from expert sources as cited (with permission) in each section. This information is scientifically based.  E-Fauna BC also acts as a portal to other sites via deep links.  As always, users should refer to the original sources for complete information.  E-Fauna BC is not responsible for the accuracy or completeness of the original information.


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