Wednesday, February 6, 2013

Finally sunshine -- finally back to the streams

The weather's been working against me.  I returned to VA last Thursday, to streams that were high and off-color, to gray cloudy days, and to temperatures that didn't get up to freezing.  At last, today it was sunny and warm.

This morning, I made a quick stop at the Doyles River, then I moved to Sugar Hollow to look at a small stream to which I've not been for a year.  Let me start there with a report on the insects I found.

1. In the photo at the top of the page, one of the most common things that I found, a Lepidostomatid case-maker caddis.  (According to Thomas Ames, by the way, the common name for this type of caddis is the "scaly-mouth caddisfly.")  I saw a lot of them -- always in leaf packs -- and most were in the "multi-media" cases: partly grains of sand and partly four-sided sections of leaves.

It's their time of year in these small mountain streams.

2. The common stonefly, Eccoptura xanthenses.  I saw several of them -- also a small mountain stream taxon -- and was surprised by their size.

3. Green stoneflies (Chloroperlids, genus Sweltsa).

4. And a Uenoid caddisfly larva, Neophylax mitchelli.  This is the one with the long, thin, backward pointing tubercle on its head.

I also saw quite a few flatheaded mayflies, the species we expect to see in this kind of stream at this time of year: Maccaffertium merririvulanum, Maccaffertium pudicum, and Epeorus pleuralis.  And there was a fair number of large winter stoneflies, Taeinionema atlanticum.

Now, back to the Doyles.  The Doyles is still running high from all of the rainfall last week, but I did manage to find a few things of interest.

1. The large winter stonefly, Strophopteryx fasciata.  I did not see any Taeniopteryx burksi/maura -- they might be hatching.

2. The small minnow mayfly, Heterocloeon amplum.  I found quite a few, but they're still pretty small.  Still no sign of the rich colors we'll see later on.

3. And the spiny crawler mayfly, Ephemerella invaria.  You'll recall that this is the species we see in the winter: the spiny crawler "hordes" that invade our streams in the spring are E. dorothea.

Most E. invaria spiny crawlers have two visible distinguishing features: 1) the pale yellow line that runs between the eyes, and 2) paired tubercles on the posterior edges of abdominal segments 3-8.  On this nymph, each tubercle shows up as a light colored dot.

A closer look reveals those tubercles, as well as the posterolateral projections on segments 4-9.

4. I also found Uenoids at the Doyles River.  I only kept one, since I was sure they were N. oligius.  I was wrong, and I need to do some work on this larva before I decide on the ID.  I now wish I had kept a few more!


Good to be back in business.  Sunshine again on Saturday -- or so they say at the moment.

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