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Phanogomphus graslinellus
Pronghorn Clubtail
Family: Gomphidae
Species account author: Robert Cannings.
Extracted from Introducing the Dragonflies of British Columbia and the Yukon (2002)


Photograph

© George Doerksen     (Photo ID #1037)

Map

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Distribution of Phanogomphus graslinellus 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 green; the thorax is grey-green to yellow, with two brown stripes of about equal width (both stripes are often divided into pairs of thinner ones); the abdomen is black with a yellow stripe on top of each segment, and yellow spots on the sides, larger near the tip. The English name comes from the shape of the male’s upper appendages: like the horn of a Pronghorn antelope. Length: ♂ 48 mm, ♀ 50 mm.


Flight Period

B.C., late May to early August.

Genus Description


A large genus, especially numerous in eastern North America, but only a single, rare species enters B.C. in the southern interior.

Biology

Family Description

A large family, but poorly represented in our region. B.C. has only six species and the Yukon appears to have none (although two species may live in the southeast). Compared to some other families, clubtails are not common here, but they are easily recognizable by their widely separated eyes and their green or yellow bodies striped in brown and black. The tip of the abdomen, especially in males, is enlarged, giving them their English name. Females lack an ovipositor and drop their eggs directly into clear streams and along the sandy shallows of larger lakes; they lay their eggs without the protection of their mates. Larvae burrow in the bottom sediments of these water bodies.
Field Notes

A rare species of warm lakeshores and streams. Larvae burrow in sand along wave-washed shores, especially where mats of water weeds grow offshore; when ready to emerge, they crawl only a few centimetres up the beach to metamorphose. Adults bask on sunny ground near water. When disturbed, they have a characteristic undulating flight.

Distribution


Transition. In B.C., found only in southern interior valleys.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
NativeS2S3BlueNot Listed



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