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Cordulegaster dorsalis
Pacific Spiketail
Family: Cordulegastridae
Species account author: Robert Cannings.
Extracted from Introducing the Dragonflies of British Columbia and the Yukon (2002)

Photograph

© Ian Lane     (Photo ID #1179)

Map

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Distribution of Cordulegaster dorsalis 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 face is yellow with a dark line; blue eyes barely meet at a point on top of the head. The body is black, with yellow stripes on the thorax and yellow spots on top of the abdomen. Length: ♂ 75 mm, ♀ 80 mm.


Flight Period

B.C., mid May to early September (most are seen in July).

Genus Description


Closely related to Common Clubtails, but fly later in summer and fall. Only one of twelve North American species lives in B.C., a rare inhabitant of the southern interior. Males often patrol back and forth over the water, then land on leaves and twigs that bend under their weight, leaving them hanging nearly vertically.

Biology

Family Description

Large black-and-yellow dragonflies with eyes meeting at a single point on top of the head. Spiketails live along streams where the males patrol steadily up and down for long distances. The English name comes from the female’s long, spike-like ovipositor, used for placing eggs in streambeds. The large, squat, hairy larvae bury themselves in the sediment to await their prey.
Field Notes

One of our largest dragonflies. Fairly common along small coastal woodland streams flowing from lakes; rare east of the Coast Mountains in southern B.C., and where it does occur, it flies along small warm streams, especially ones fed by springs. Egg-laying females hover vertically, moving up and down, shoving eggs into the sand and silt of the streambed. Perches vertically.

Distribution


Montane. Coastal valleys; southern interior to about 51°N.

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.