One of the strangest critters we see in our streams -- some of them -- in the summer: a whirligig beetle larva (Gyrinidae), genus, Dineutus. The genus ID is determined by the shape of the head: if it's "elongate" it's Gyrinus; if it's "semi-circular" it's Dineutus. Hard to believe that this odd-looking thing turns into a black beetle that, as an adult, swims on the surface. (For pictures of Dineutus adults, go to: http://bugguide.net/node/view/95/bgimage?from=96.) The key feature in family ID is the four terminal hooks on the final abdominal segment -- which you can see in this photo if you click on it to enlarge it.
Actual size -- around 1" long.
Gyrinidae larvae inhabit the tangled, coarse vegetation that grows on a lot of the rocks in Buck Mt. Creek in the summer. So too do immature brushlegged mayflies and common netspinners, the two most common insects that I saw this morning. On the bottoms of the rocks, on the other hand, it was all flatheaded mayflies and small minnow mayflies. There are still a lot of Epeorus vitreus flatheads in Buck Mt. Creek -- they'll probably be here most of the summer -- and the Heptagenia marginalis nymphs are also showing up in pretty good numbers.
E. vitreus (a young one):
H. marginalis, also a young one:
On the small minnow mayflies -- I found the same two species I've been finding in my other "small minnow" streams: Baetis intercalaris and Beatis pluto.
B. intercalaris (male):
But, as the song says, "I still haven't found what I'm looking for": the small minnow mayfly Acentrella nadineae. This one (found in the Doyles River last year on June 23).
They're very distinctive with the orange/red splotches on the terga and the thorax, and by now, I've been to every stream where I found them last year: Powells Creek, the Doyles River, the Lynch River, and Buck Mt. Creek. I've not yet seen a one. Just have to keep looking.
Below: one of several small, common stoneflies -- genus Acroneuria -- that I found this morning. This one will mature over the winter.