Overview:  Dennis Paulson, of Puget Sound University, was the first to describe the Columbia (or Lynn's) clubtail in 1983.  The Columbia clubtail is a member of the Anisoptera sub-order, which includes all North American dragonflies.  Dragonflies have very keen eyesight and are able to move each of their four wings independently, enabling them to maneuver through the air with unparalleled speed and agility.  These insect aerialists pursue flies, mosquitos, butterflies, midges and other dragonflies--nabbing them in mid-air with specialized legs, which can form a sort of basket to hold their prey.  Its larvae, or nymphs, are aquatic and also carnivorous, feeding on other aquatic invertebrates, tadpoles and even small fish.  The mouth of a dragonfly nymph is specially equipped with a long, double-hinged, toothed appendage (labium), which serves to grasp and immobilize prey while the forelegs tear it apart for consumption.  Female Columbia clubtails lack ovipositors and drop their eggs directly into clear streams that have relatively open canopies.  When they hatch, the nymphs will burrow into the silt or mud, leaving only their head and tail-end exposed.  The streams that provide suitable habitat for Columbia clubtail are threatened by continued water drainage and diversion for irrigation and development purposes, as well as stormwater run-off containing pesticides.  The Yakima River population is threatened by increased numbers of carp, an introduced species that may be lowering stream productivity by stirring up sediment, which muddies the waters.  Increased numbers of mosquitofish pose another threat to Columbia clubtail populations because they compete with dragonfly nymphs for small aquatic organisms.

Distribution: In Washington, sightings of Columbia clubtail have only been confirmed along the Yakima River in Benton County, Washington.  Oregon sightings of Columbia clubtail include locations along the John Day River and Owyhee River in Grant, Malheur and Wheeler Counties.  Populations are suspected to occur along the Grande Ronde River as well, but this has not yet been verified.