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Western Flying Adder (Cordulegaster dorsalis)

Detailing the identifying qualities of the Western Flying Adder, including physical features and territorial reach.

 Updated: 2/10/2014; Authored By Staff Writer; Content ¬©

  Western Flying Adder  
Picture of Western-Flying-Adder

Western Flying Adders are long, hairy dragonflies that are quite at home in the Pacific Northwest.

The Western Flying Adder is part of the very common summer flying insect generically grouped as "dragonflies". They appear quite large when compared to most insects measuring about 70mm to 85mm in length. With their wings spread, they can hit widths of up to 135mm. Coloring on these creatures is quite impressive, yielding an almost brown to black surface with accents of yellow at intervals.

Western Flying Adders, like most other dragonflies, can be found near streams and woods. This particular species is "western" thanks to a range that lies west of the Rocky Mountains and north into Canada. Unlike other dragonflies, Western Flying Adders are not particularly aggressive toward other species of dragonflies.

In early spring, females will insert their eggs into soft wood or plants near creeks or streams using a long syringe-like ovipositor. The young, hairy naiads (juveniles) hatch and then make their way to into water and burrow into the sandy or silty bottom. They emerge from these hiding spots to feed on other aquatic insects using their large spoon-shaped lower lip. They mature rather quickly and are fully developed adult by late spring.

Western Flying Adder Information

Category: Dragonfly or Damselfly
Common Name: Western Flying Adder
Scientific Name: Cordulegaster dorsalis
Other Name(s): Pacific Spiketail

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Odonata
     Arrow graphic Family: Cordulegastridae
      Arrow graphic Genus: Cordulegaster
       Arrow graphic Species: dorsalis

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 70 mm to 135 mm (2.73 inches to 5.265 inches)
Identifying Colors: green; black; yellow
Additional Descriptors: flying, hairy

North American Territorial Reach (Though Not Limited To): California, Idaho, Montana, Nevada, Oregon, Washington

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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