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

Aeshna juncea
Sedge 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 #4618)

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


Description

Thorax stripes are yellow-green below, blue above and bordered with black; shape shown in figure. The face is yellow to yellow-green with a black line. Pale spots mark the undersides of the abdominal segments. The pale areas on females are usually green or yellow-green, but on some they are blue. Male’s upper appendages simple. Length: ♂ 66 mm, ♀ 65 mm.


Flight Period

B.C., mid June to early October; Yukon, late June to mid 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

Uncommon in southern valleys in B.C. More common at higher elevations and northward, it is the most common darner in the Yukon. Lives in a variety of habitats, mainly containing acidic waters, but it is most abundant in peatlands dominated by extensive stands of sedges.

Distribution


Northern; also across northern Eurasia. Widespread in B.C. and north almost to the treeline 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.

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: 2021-10-22 12:06:10 AM]
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.


© E-Fauna BC 2021: An initiative of the Spatial Data Lab, Department of Geography, UBC