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 VIVID
DANCER
Argia vivida
Family Coenagrionidae - Narrow-Winged Damselflies
Order Odonata - Dragonflies and Damselflies
Risk Status
Official status
The Vivid Dancer has been assigned Threatened
status (CDC = G5 S2)
in British Columbia.
Image Credits: Vivid Dancer sketch
by Hannah Nadel in 'Rare Invertebrates of the South Okanagan' brochure;
photo by George Doerksen
Distinguishing features
Most North American damselflies belong to a family called Narrow-winged
Damselflies (Coengrionidae). These small insects, (28-43 mm long)
are brightly coloured with usually clear wings, which they hold
together vertically over their bodies when at rest.
Unlike broad-winged damselflies, narrow-winged damselflies have
wings so narrow at the base that they appear stalked. In most species,
males are more brightly coloured than females. Naiads,
to 25 mm long, have leaflike gills at the tip of their abdomen and
usually inhabit quiet waters.
Argia species generally have purple and blue bodies with
a few black markings, or brown to yellow with many black markings.
The tibiae bear 2
rows of stiff bristles and the clear wings are stalked only to the
level of the first crossvein.
The Vivid Dancer (Argia vivida) is a beautiful, intensely
(i.e. vivida = vivid) blue damselfly. In British Columbia,
it lives in a number of localities in the southern Interior.
Distribution
Map
Red dots indicate specimen records or confirmed breeding sites.
British Columbia
In British Columbia, the Vivid Dancer is known only from streams
flowing from springs. All but two of the localities are creeks and
ponds associated with hotsprings and therefore under tremendous
pressure from commercial development. In the Okanagan the main sites
are a cool spring near Madeline Lake, west of Penticton, threatened
by cattle trampling, and a second spring-fed stream near Okanagan
Falls.
Outside of the Okanagan, Vivid Dancer has
only been recorded from Field and Fairmont in the Rocky Mountains,
Meager Creek Hotsprings, Nakusp Hot Springs, Albert Canyon and a
few other hotsprings.
North America
The Vivid Dancer ranges from eastern British Columbia and the Rocky
Mountains of Alberta south to Texas, California and Mexico.
Habitat
This is a very local insect found around pools near springs or
spring-fed streams inhabited by larvae. The species is associated
with warm springs at Banff and Fairmont but with cool springs in
the Okanagan Valley. It has been said that this species is so dependent
on springs in BC that its presence anywhere may be taken as proof
that a spring is nearby.
Why is it endangered?
Rare invertebrates of the south Okanagan and Similkameen valleys
such as this species are threatened not by direct exploitation,
but by loss or degradation of their habitats. They are at risk because
their ecosystems are at risk.
The grasslands of the southern interior of the province are a
valuable agricultural resource, and their rich soils have been ploughed
and irrigated to produce tree fruits, grapes, and vegetables. Pesticide
use has probably had a great impact on native insects living in
around agricultural areas. As well, heavy grazing has altered the
plant composition of grasslands, changing the invertebrate communities.
Most accessible hotsprings in British Columbia have already lost
their unique flora and fauna by water diversion into swimming pools.
The only population of Vivid Dancers not associated with a hotspring
are in serveral small cool springs near Penticton in the South Okanagan.
Some are affected by cattle or horse trampling around their margins.
The massive diversity of invertebrate species in British Columbia
makes it very difficult for entomologists to do a literature or
collection survey to determine which species are endangered or threatened.
Specialized, detailed surveys will be required for almost every
species that is suspected of being endangered. Despite a general
ignorance about invertebrate distribution, information is known
about a number of species that are confined to threatened habitats
of very limited extent in the Thompson-Okanagan valleys.
Biology
Argia females lay eggs in aquatic vegetation or wet wood,
often submerging themselves in the process for half an hour or more.
Meanwhile, the males protect their mates from the attentions of
other males by retaining their mating hold of the female's thorax
and standing stiffly at attention. Larvae are usually found in running
water.
The aquatic larvae cling to the undersides of stones and roots
in the small, trickling streams and muddy pools. The adults rest
on stones or bare earth nearby, or make low foraging flights after
small insect prey. They are alert, seldom resting long in one place
and will dodge into vegetation if alarmed frequently.
Adult feeds on smaller soft-bodied insects. Larvae prey on aquatic
insects.
Sources for more
information
Related On-line Sites to Visit
Living
Landscapes
Publications
Cannings, R.A. 1990. List of invertebrates of special interest.
In South Okanagan conservation strategy 1990-1995, ed by D.A. Hlady.
Appendix 4.
Cannings and Stuart. 1977. The Dragonflies of British Columbia,
RBCM Handbook No. 35.
Cannings, R.A. 2002. Introduction to the dragonflies of
British Columbia and the Yukon. Royal BC Museum, Victoria.
Biodiversity of BC, Cannings, Ch4, p. 48, 1994
Rare Invertebrates of the South Okanagan, brochure, MOE, March
1995
The Audubon Society Field Guide to North American Insects and
Spiders, Milne and Milne, 1980.
Museum Specimens
this section sponsored
by: 
Industry Canada
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