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Macromia magnifica
Western River Cruiser
Family: Macromiidae
Species account author: Robert Cannings.
Extracted from Introducing the Dragonflies of British Columbia and the Yukon (2002)


Photograph

© Jamie Fenneman     (Photo ID #4617)

Map

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Distribution of Macromia magnifica 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 dark brown marks. Its grey eyes meet broadly on top of the head. The body is dark brown with a single yellow stripe on the side of the thorax and yellow bands on top of the abdominal segments. The thorax is faintly metallic, thinly pruinose with age. The legs are unusually long. Populations around Shuswap Lake and in the Fraser Valley are darker than those from drier valleys – the yellow bands on abdominal segments 3 to 6 are reduced to small, divided spots; they were once considered a separate species, Macromia rickeri. Length: ♂ 69 mm, ♀ 71 mm.


Flight Period

B.C., early June to late September.

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 brown-and-yellow dragonflies of rivers and wave-washed lakeshores, where the adults fly out over the water. The thorax is encircled between the wings by an oblique yellow band. Larvae sprawl on the bottom silt and sand; they have long spider-like legs and a horn-like projection between the eyes.
Field Notes

Uncommon along warm lake margins and sandy rivers. Males patrol with a swift, direct flight, low over the water, but like other large dragonflies, cruisers often feed in open areas far from water. Females lay eggs alone, striking their abdomens on the water surface. Both sexes perch vertically on vegetation.

Distribution


Montane. Fraser Valley; southern interior valleys south of 51°N; not recorded in the Columbia or Kootenay river valleys.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
COSEWIC
NativeS3BlueNot Listed



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