The plan was to go to Buck Mt. Creek where I'm sure the winter insects -- H. amplum small minnow mayflies, Clioperla clio Perlodids, etc. -- are fairly mature. But BMC is still high, fast, and off-color. I'm still restricted to the small, first order streams in Sugar Hollow: I'm not even sure that the Rapidan is doable yet.
My choice today was a small stream that spills into the Moormans not far from the first bridge. This is only the second time that I've stopped there. I sure didn't have to look very hard to find lots of interesting insects. While here, too, the E. dorothea spiny crawlers dominated my findings, I was most excited about this free-living caddisfly larva, Rhyacophila carolina, one that I've only seen in a few of our streams. Tolerance value: 0.4.
There are three features that distinguish this species, one is the color of the head and pronotum: golden brown (Beaty, "The Trichoptera of North Carolina," 60). That's very clear in all of my pictures.
Number two -- there are no ventral teeth (denticles) on the anal claws.
And number three -- the sides of the head are "rounded," not "parallel." Compare R. carolina with R. nigrita.
R. carolina, according to Beaty, is the "second most common Rhyacophila in NC."
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For the rest, pretty much what we'd expect to find in a small mountain stream at this time of year.
1. Spiny crawler mayflies, E. dorothea. As I did at the Whippoorwill last week, I found both the large nymphs that are dark brown with a pale dorsal stripe, nymphs that are already fairly mature,
and some much smaller nymphs that still have a long way to go. However, these E. dorotheas were not so much "speckled" -- as those at the Whippoorwill were -- as highly patterned, and one was a very odd color, very orange.
2. A Limnephilid (Northern case-maker), genus Pycnopsyche -- the one with the three-sided case made out of segments of leaves.
3. Common stonefly, Eccoptura xanthenses. I saw quite a few -- this was their kind of stream.
4. And as you can see in that photo, I found some Uenoids, including two very small Neophylax aniqua. Here is a close-up of the one in the photo above. The blunt tubercle on the head is visible even though the larva was only 2.5 mm.
Here's a second N. aniqua: this one was 3 mm long.
I also found two N. concinnus Uenoids: the photos of this one were the best.
N. concinnus larvae have a small, rounded tubercle on the head which you can see if you enlarge this photo. They also have a "spiculate" pattern on the frontoclypeus and fairly large spines on the anterior of the pronotum.
And no clavate gills.
Note the difference in size of two of the E. dorotheas.
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