Thursday, November 1, 2012

Damselflies in November? Really?

Guess so -- in Buck Mt. Creek, anyway.  It turned out to be the very same species that we see in the Rivanna during the summer, Calopterygidae (Broad-winged damselfly), Hetaerina americana, the American Rubyspot.  Surely this nymph was confused by the warm weather we had in October.  Not very warm now.

Now, for the second title to use for this entry -- "Did I Happen to Mention that They Grow Up in a Hurry?"

The Perlodid stonefly, Clioperla clio:

Even nicer than the one that I found here last week (10/25) and certainly much more developed than the one I found just two weeks ago (10/13) at the Doyles.  The mature colors and patterns are really starting to show.

And look at these two small winter stoneflies.  The long one measured 8 mm, and small winter stoneflies -- genus Allocapnia -- don't get a lot bigger.

For comparison, look at the photos of small winter stoneflies posted on 10/11 and 10/25.

Both of the small winters pictured above are Allocapnia in terms of the genus (look at the rear wing pads in the photo below).  I can't tell you the names of the species, that's something I'll work on over the winter.  But, I don't think these two are the same in terms of the species.   (There are 19 species of Allocapnia small winters in the state of Virginia.)   I'll make the case for that when I collect nymphs that are more mature.  Still, in the meantime, look at the differences in this microscope photo in which they're placed side-by-side.

The nymph on the left has tiny rear wing pads: those on the nymph to the right are much larger.  Then too, the front wing pads on the two nymphs do not overlap the rear wing pads in the same way.  And there's the different abdominal colors.

But Allocapnia species ID isn't easy, and I know from the reading I've done that outward appearance is not all that important in terms of the keys.  More on this later on: we'll be watching the small winters grow and develop in November and December -- even into the start of next year.

(Today's photos are not the best.  Still gray and cloudy -- no sun.)

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