Cedar River at Landsburg Reach, King County, Washington, USA September 3, 2012 Size: 6 mm
I found quite a few of these crawling on the undersurface of several rocks lying in the stream bed. They ranged in size from 4 to 7 mm. At first I thought they might be stonefly nymphs, but they each had three cerci so I'm sure they are mayflies.
Contributed by Dick Palmer on 5 September, 2012 - 6:01pm Last updated 3 October, 2012 - 11:06pm
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