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Image Credits: Vivid Dancer sketch by Hannah Nadel in 'Rare Invertebrates of the South Okanagan' brochure; photo by George Doerksen 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 inhabit quiet waters. The 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 found in the southern Okanagan.
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British Columbia Outside of the Okanagan, Vivid Dancer has only been recorded from Field and Fairmount in the Rocky Mountains, Meager Creek Hotsprings, Nakusp Hot Springs, Albert Canyon and from Glacier in the Selkirk Range.
North America
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 two small cold springs near Penticton in the South Okanagan. Both are being severely impacted 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. 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. Related On-line Sites to Visit
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