Monday, December 12, 2011

Looking for "big" Small Winter Stoneflies at the Doyles River

I didn't find any.   When I went to the Doyles on 10/25 (see the entry) I found a lot of small, small winter stoneflies.  So, I felt sure that I'd find some mature ones today.  Not so.  I did find some -- but they were not very big, and my photos aren't really worth showing.

But I did find a lot of Clioperla Perlodid stoneflies (e.g. the one in the photo above), and some of them were very big indeed!  Notice the rich colors and patterns, and note how the rear wing pads are spreading away from the body.  I'm still very surprised that the Clioperlas (Clioperla clio, to be exact) are this large in this early part of the season.

My other findings today were large winter stoneflies (genus Taeniopteryx) which are also getting mature, small winter stoneflies (which were surprisingly immature), a fair number of Diploperla Perlodid stoneflies, and one lonely Chloroperlid (Green stonefly).  I didn't see a single mayfly -- not even a flathead.

Some photos.

1. Large winter stonefly (genus Taeniopteryx)

2. Perlodid stoneflies (Diploperla duplicata)

3. Chloroperlid stonefly (genus Sweltsa)

The Chloroperlid was in the river at Doylesville (bridge at Blufton Road); I've never seen this stonefly family further downstream where I sample (below the bridge at Rt. 674).

The difference in size in color of this Chloroperlid with the one that I found yesterday is dramatic and striking.  But, I was in a high mountain stream yesterday where things are a little behind what we find down in the valleys.  This Chloroperlid may turn out to be a Sweltsa lateralis and look like this nymph that I found on May 4th in the Rapidan River.

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