Thursday, April 10, 2014

It's a show-stopper: the "common burrower" Ephemera guttulata

What else can you say?  This is a mayfly we don't see very often -- and it's really unique.  Ephemera guttalata, which will hatch as the "Eastern Green Drake."  But forget it fly fishermen -- this small stream in Sugar Hollow doesn't hold any trout.  It's a "common burrower" (Ephemeridae), and the only way to find them is to "burrow" in the substrate -- which is what my friend was doing while I sorted through leaf packs.  We were in the same stream where she found this E. guttalata -- much more mature (much darker with much longer wing pads) -- on May 1, 2012.

Beaty's description reads as follows:

guttalata -- nymphs up to 20 mm; frontal process long, notch deep, approximately half the length of the entire process; body brownish overall; both fore- and hind wing pads heavily blotched with irregular dark spots; abdomen broad, generally lacking any distinct color pattern, both dorsally and ventrally.  Collected mostly during spring and summer.  Mountains only.  Uncommon.  Recorded from GSMNP [Great Smoky Mountains National Park].  ("The Ephemeroptera of North Carolina," revised, October, 2013, p. 84)

Here is a look at the frontal process and the wing pads on the nymph that we found today.

But they show up much better on the nymph from 2012.

Abdomen without a distinct color pattern?  Absolutely.

Ephemera guttalata.  Tolerance value: 0.0.


But this little stream held some other treasures as well.  Like this caddis case-maker Pycnopsyche gentilis.

Take a close look at that case.  This is the species that often initially makes a three-sided case out of leaves...

But then changes to one that's made out of pebbles.

The one I found today was in the process of making the change.  The rear of the case is still made out of leaves; the front is now converted to pebbles.

Very cool!

One more treat.  a fully mature Perlodid stonefly, Malirekus hastatus.  We've found some lately that have been very close -- but here we have the black wing pads.


One other insect of interest.  We saw hundreds of Roach-like stoneflies, as we commonly do in these streams at this type of year.  But today, we may have had more than one species.

This one is genus Peltoperla for sure.  Note the three dark spots on the meso and metanotum.

And as you can see, there are "double" gills at the rear of the nota.

 This nymph is not Peltoperla: it may be Viehoperla ada.   Viehoperla nymphs have single gills on the thorax, and I could only see one on this nymph.

But to be certain of the ID, I should have preserved it.  Instead I dropped it into the leaves!

Lots of other insects around: pronggilled mayflies, Isoperla similis stoneflies;

 Ameletid mayflies as well (Ameletus cryptostimulus);

And it was a nice, sunny day.


Oh.  There are still a lot of Uenoids in this little stream: N. aniqua and N. mitchelli.  Caught this mitchelli crawling up over the Pycnopsyche case.

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