I made a quick trip to the Lynch River today, hoping to find some small square-gill mayflies. None around. I did see a fair number of small minnow mayflies -- Acentrella turbida -- the same species on which I reported in entries posted on 9/30. So, I thought I'd at least get some nice photos of them.
This was the most uncooperative group of small minnow mayflies I've run into all year. To begin with, I only found one that was mature (actually, ready to hatch), and it was crawling around in a leaf pack -- which they don't normally do -- so it was covered with mud! Still, if you look closely you can see the setae (hair) on the tibiae of the second set of legs. Remember that long, dense setae on the femora, tibiae and tarsi is key to identifying this species.
Not a photo that elicits oohs and aahs! As for the rest of the nymphs I collected, they were all very small, and they were constantly on the move in my tray! I couldn't get them to settle down and pose. When they did take a respite, they flipped up their abdomens -- like the nymph in the photo at the top of the page: not the view I was after!
I was anxious to get some good shots of these squirts because they were as broad (thorax) as small minnows can be. Had you seen them scooting around in my tray, you might not have guessed that they were small minnow mayflies: they were virtually as wide as they were long. Very odd looking things -- but very clearly Acentrella turbida since that broad thorax is one of the things that gives that species away.
A few other "failures" -- for what they're worth.
1) Almost a good shot, as one of the little nymphs crawled atop the mature nymph, which had flipped on its back!
2) And another near miss, as two of the little ones decided to wrestle!
3) And finally -- well, who knows what they were doing?!
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