This one pretty clearly keys to Kogotus, but it also looks fairly different from specimens I caught in the same creek about a month later in the year. With only one species of the genus known in Washington, I'm not sure about the answer to this ID.
These specimens were collected from a mating swarm from the east branch of the North Fork of the Touchet River, upstream from the Bluewood Ski Area turn.It was a sunny warm day, mating swarm as 4-8 ft. above this small stream. Four male spinners were collected.Stream photos were taken.
Entoman on Jul 15, 2011July 15th, 2011, 9:04 pm EDT
A-man,
The purpose of these long legs is to grasp the female in a way that proper leverage and balance can be utilized to make aerial copulation possible... Founders of the mile high club?
Kurt
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman