Thursday, January 9, 2014

Checking the Uenoids at Entry Run and South River: N. concinnus for sure and possibly N. ornatus

There's an experiment I've been wanting to try, so I went for it today -- never mind that it was 34 degrees when I went into the water.  I went back to Entry Run and South River up in Greene county.  Here's the location:

Entry run is a small, first order stream that flows into South River at a point where South River is already a second order stream.  My question was:  If I look at Uenoids in Entry Run, then do the same in South River at this location, then move 5-6 miles downstream to another site on South River, what species of Uenoids am I going to see in each of those locations.

The results in a moment.  First, some photos of my other findings today.

1) That beautiful stonefly in the photo at the top of the page: Acroneuria carolinensis.

2. Small minnow mayfly, Baetis tricaudatus.  I saw more than one.

3. Green stonefly (Chloroperlid), genus Sweltsa.  Saw quite of few of these nymphs.   They like Entry Run.

4. Large winter stonefly,  Taeniopteryx burksi/maura.

5. Large winter stonefly, Taenionema atlanticum.  What a beautiful color!

6. Flatheaded mayfly, Epeorus pleuralis  -- or possibly Epeorus fragilis.  I should have kept it to check it for sure.  In any event, the rocks in South River at the upper location are covered with Epeorus nymphs at the moment.

7.  And a pronggilled mayfly, genus Paraleptophlebia, species -- possibly mollis.  Many, many of them at the moment in Entry Run.

8. Perlodid stonefly, Isoperla montana/sp.


Now back to the question about the Uenoids.  What did I find?

1.  In South River at the upper location -- directly above that bridge in the photo above, i.e. before Entry Run enters the stream -- I found Neophylax consimilis.  Some pictures.  (Notice the little Diplectrona netspinnner holding on to the side!)

In this photo it's tough to see the "pale spot" on the frontoclypeus that is often found with this species.  But we can see that spot and the clavate ventral gills in this microscope view.

2. Five miles downstream from this site, I picked up two Uenoids which turned out to be Neophylax concinnus.

This marks a first for us, and this species will be added to our EPT list.  In a stream system, N. concinnus is typically found between less tolerant species upstream -- N. aniqua, N. mitchelli, N. consimilis -- and the downstream more tolerant species, N. oligius and N. fuscus.  N. concinnus larvae do not have clavate ventral gills, and at the ventral sa3 position, there are typically 2-4 setae.  Also, they typically have a "short median tubercle" on the frontoclypeus as in the photo above.  Voila!

For the detailed description of N. concinnus, see Vineyard,, The Caddisfly Genus Neophylax, p. 46.

3.  Now, back to Entry Run.  I found two Uenoid species: one we know, the other we don't.  One was N. consimilis, the same species that I found across the road in South River.  (Same elevation.)

But the other species is a mystery at the moment -- possibly N. ornatus, possibly N. atlanta.  In my tray, I thought both cases were empty since the larvae did not emerge.

However, when I turned one case over, I thought I could make out some legs sticking out at the top.

Both cases were inhabited, and through the microscope this was the view looking down on the head/face.

That's a very odd pattern of light and dark, and note the light muscle scars behind the eye.  Both larvae had clavate ventral gills, and the spines on the anterior of the pronotum were very pronounced: long and sharp.

I can't ID this one at the moment.  I'll need to send this to Beaty to help me with the ID. More on that when I hear something for sure.

Always worth freezing if you can find some new species!

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