Saturday, October 13, 2012

Clioperla clio: Another Perlodid Shows Up for the New Season

I saw a real mixture of insects at the Doyles River this morning, including more, tiny, small winter stoneflies and very small Perlodids, Helopicus subvarians (look at the previous entry).   But this was the new one, making its debut for the season: the Perlodid stonefly, Clioperla clio.  It was a small one, all of 4 mm.

I was not surprised to see this nymph in this river, C. clio Perlodids show up in big numbers here every winter.  They're beautiful stones, but they're vicious:  if you monitor streams, don't put them in the same tray with small minnow mayflies -- they'll gobble them up in the blink of an eye!

So, at the moment they look like this,

but in a couple of months they'll be very colorful insects.  (This photo was taken in December last year.)


Here's a look at the rest of the day's findings.

A. Stoneflies

1. Perlodid stonefly: Helopicus subvarians.  This one was a little bit bigger than those that I found on Thursday, measuring 4 mm.  And note how the colors and patterns are already starting to change.

2. Common stonefly: Acroneuria abnormis.  A real beauty.

3. And another tiny small winter stonefly -- about 3 mm.  I expected to see a lot of them: this is the only one that I found.


B. Small minnow mayflies

1. Plauditus dubius, female and male

2. Baetis intercalaris, male.  These seem to be in the streams from the start of the spring 'til the end of the fall.

3. Baetis pluto, male.  The pale color of the 5th tergite gives this species away.


I should note that I am not taking photos of the most common insects I'm seeing: small brushlegged mayflies (both in Buck Mt. Creek and in the Doyles), small flatheaded mayflies -- no way I could identify them, and fingernet caddisfly larvae, also fairly small at the moment.

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