Thursday, August 14, 2014
And it's another, unidentified, summer Lepidostomatid: Doyles River this time
I wasn't sure where to go to this morning, and I'm not terribly thrilled with my choice. Still, I haven't looked in the Doyles for a long time, and I was expecting to see lots of small minnow mayflies. I didn't. I saw one, small, Baetis intercalaris. Mostly, I saw tiny flatheaded mayflies and common netspinner larvae.
Just this one item of interest. I spotted what looked to me like a case on the side of a rock and put it into my bowl hoping to see a caddis larva stick its head out. Nothing. It took about 20 minutes before I saw a little head and some legs.
Off to the car to get my camera and set up my gear. Then I waited and waited and waited -- nothing ever came out of the case. Still I took some photos, and as you can see in the photo at the top of the page, the larva did at least peek outside of its case. A few more views. (Look closely at the opening at the top.)
Of course when I put it into a vial for preservation it immediately emerged.
It was a very small larva -- about 6.5 mm. But like the larva I found last week at the Rivanna, it was genus Lepidostoma. Whatever the species, it clearly differs from those that we find in the winter. I'd venture a guess that this larva was also distinct from the one I found at the Rivanna.
Remember that Beaty lists over 20 species of Lepidostoma in North Carolina, most of which remain undescribed. A very distinctive feature of this particular larva -- dark head, pronotum, and mesonotum with very pronounced light colored muscle scars throughout. I wish I could show that to you with photos, but I dropped the tray in my lab, and there was no way to find such a small larva on a light colored speckled rug. Oh joy. Still, you can see the muscle scars on the head in the one photo I managed to take.
Very unusual. I hope to do the Rapidan River tomorrow. Sunday, it's off to Montana!