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Ischnura cervula
Pacific Forktail
Family: Coenagrionidae
Species account author: Robert Cannings.
Extracted from Introducing the Dragonflies of British Columbia and the Yukon (2002)

Photograph

© Kathryn Clouston     (Photo ID #69651)

Map

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Distribution of Ischnura cervula in British Columbia.
(Click on the map to view a larger version.)
Source: (for the static map) RBCM and BCCDC 2004 ©

Species Information


Description

Male’s thorax has blue sides and a black top with two pairs of pale dots; appendages shown in figure. Female’s thorax is sometimes coloured like the male’s (dots elongated), but more often green or tan to pink with dark lines of variable thickness above; the abdomen has a blue tip. Most females darken with age; they often have a vulvar spine. Length: ♂ 29 mm, ♀ 30 mm.


Flight Period

B.C., early April to late October.

Genus Description


Found almost everywhere dragonflies live, though mostly absent from boreal habitats; distribution in North America is decidedly southern. B.C. has four species, but only the two most widespread – the Pacific Forktail and the Western Forktail – are encountered often. None are found in the Yukon. Male forktails in B.C. are mostly black, blue and green. The abdomen is black above and has a blue tip; the last segment bears a distinct forked projection on top, which gives the group its English name. Females may be the same colour as males or may have a tan, pink or orange thorax when immature; they may darken with extensive pruinescence as they age. Larvae are similar to those of bluets, but the gills usually have long, tapered tips.

Biology

Family Description

Small damselflies that normally perch with wings closed above the abdomen. Most males are blue marked with black, but the main colour may be green, yellow, orange, red or purple. Females often have two colour forms per species, one similar to the male (usually blue). Females lay eggs in the tissues of water plants, sometimes completely submerging themselves for a long time while laying. Larave are not as long as spreadwing larave and have short labia, unstalked at the base. There are six genera and 18 species of pond damsels in our region. The American Bluets (Enallagma) and forktails (Ischnura) are the most common groups.
Field Notes

One of the most common damselflies of low and moderate elevations across southern B.C. Most common around marshes and the marshy edges of small lakes and ponds; the only dragonfly that often flies among dense cattails and bulrushes. Prefers neutral and alkaline waters. It has one of the longest flight seasons of any dragonfly in B.C., and is usually the first to appear in spring.

Distribution


Montane. Widespread in the southern half of B.C., to about 55°N.

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.