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

Photograph

© Robert A. Cannings     (Photo ID #1023)

Map

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Distribution of Aeshna tuberculifera in British Columbia.
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Source: (for the static map) RBCM and BCCDC 2004 ©

Species Information


Description

Large and slender. Thorax stripes are green to blue; shape shown in figure. Its face is green, the face line thin and pale brown or absent. Segment 10 of the abdomen is all black, as the English name indicates. Female’s abdomen has blue spots, like the male’s. Male’s upper appendages simple with a tubercle underneath near the base; female’s appendages are large. Length: ♂ 73 mm, ♀ 75 mm.


Flight Period

B.C., mid June to early October.

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

An uncommon dragonfly of peatland pools and peat-margined lakes. Unlike most mosaic darners, females patrol like males and often lay eggs in vegetation above the waterline. Presumably, this behaviour reduces the amount of attention that males give them, allowing more time for uninterrupted egg-laying.

Distribution


Transition. Sparsely distributed across the moister regions of southern and central B.C.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
NativeS4YellowNot Listed



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