Thursday, February 21, 2013

Yet another small stream in Sugar Hollow


Love that case.  Uenoid caddisfly larva, Neophylax aniqua.

This morning, my friend in Sugar Hollow took me to yet another new stream -- or rather, a new section of a stream to which we've gone before.  We decided to go further upstream -- despite the risk of seeing some bears!  At the moment, we're seeing pretty much the same insects in all of these small mountain streams, and as I found out on Monday, it's rare that you turn over a rock without seeing a bunch of flatheaded mayflies, Epeorus pleuralis.  Some photos of these later on, but let's begin with the Uenoids since I found three different species today.

1. Neophylax aniqua.  Remember that we ID this one by looking for two different things: a short, blunt tubercle on the head, and a lack of clavate ventral gills on segment one.  We actually see the short tubercle in this photo.


I loved the case with that very large pebble on the left side.


Uenoid cases vary from stream to stream -- and from larva to larva -- since they make use of the materials they find at hand.  I was reminded of this yesterday when a friend sent me a link to an article on the work of French artist Hubert Duprat.  Duprat has removed caddis larvae from their cases and put them into a tank with pieces of gold and various jewels.  The new cases they make are really something to see.  (See http://www.cabinetmagazine.org/issues/25/duprat.php.)

2. Neophylax mitchelli.

A good chance to see just how varied those cases can be.  I was starting to think that N. mitchelli cases were mostly tubelike, sort of boring, but I was wrong.  N. mitchelli larvae have long, pointed tubercles on their heads, and they have clavate gills.  Also note how much lighter in color the legs are vs. those of N. aniqua.


The tubercle is easy to see on this one,


but it's not so clear on the others that I collected -- all of which were very small.




3. Neophylax consimillis.

This was the largest of the Uenoids I found, and what gives this one away is the pale spot/stripe in the center of the head.


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And now for the rest.  First, let's have a look at some of those E. pleuralis nymphs that are clogging up these streams at the moment.  Three different colors; three different sizes, going from the most to the least mature.

#1


#2


#3

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Three more photos.

1. Small minnow mayfly, Baetis tricaudatus.  They were plentiful but immature.


2. Rolled-winged stonefly, genus Leuctra.


3. And an Ameletid mayfly, Ameletus lineatus.  These were also fairly common.

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Monday, February 18, 2013

Along the way...just couldn't resist taking some photos


I was on a mission this morning -- to check elevation and mileage at some of the local sites where I've been finding Uenoids.  I hope, in the near future, to sum up my findings on the Uenoids I've found over the winter: which species are found where?   And by the way, the season is pretty well over; pupation is underway.  I saw more cases this morning that were sealed up than those that were open for business.

But while I was out and about, I couldn't resist looking around.  Here are some of the photos I took.

Doyles River at Rt. 674.

1. The beautiful, fully mature, male Heterocloeon amplum small minnow mayfly in the photo above.  More views.



2. At the same site, a Perlodid stonefly, Diploperla duplicata.


3. And also at the same site, a Uenoid caddis, Neophylax oligius (pale stripe down the face).


Microscope view of the face.

Sugar Hollow, small, 1st order stream, elevation 1200 ft.

1. Uenoid caddisfly larva, Neophylax mitchelli.

#1

Close-up of tubercle on the head.
Microscope view of tubercle.


#2


2. Uenoid caddisfly larva, Neophylax aniqua.

#1

Close-up of tubercle on the head.
Microscope view of tubercle

#2


N. aniqua larvae appear to be much smaller than N. mitchelli: 3 mm vs. 5-6 mm.  And I suspect that they're only found at high elevations in 1st order streams.

3. Ameletid mayfly, Ameletus lineatus.


4. And a Rolled-winged stonefly, Leuctridae, genus Leuctra.


Friday, February 15, 2013

Color comes to the Doyles as the Spring insects start to mature


It's an E. invaria spiny crawler.  It's not the first one we've seen, but it's the first one we've seen with the beautiful colors of a nymph that's almost mature.  Here are three more photos of the same insect.




My plan was to venture up to South River this morning, but in the end I headed off to the Doyles.  First stop -- up at the very top of the valley, but this spiny crawler was further downstream at Blufton Road.  So too was this colorful, male, Heterocloeon amplum small minnow mayfly.



One more beautiful insect I found at that location: Perlodid stonefly, Clioperla clio.  Note how the wing pads are starting to spread away from the body.


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At my upstream site on the Doyles, I found a totally different group of insects.   Under the rocks, the flatheaded mayfly, Epeorus pleuralis.



In all of the streams that I visit that are in or close to the mountains, E. pleuralis nymphs own the rocks at the moment.  Turn a rock over and you won't see much of anything else.  They are really prolific at this time of year in this part of Virginia, and where there are trout, they provide mighty good fishing when they hatch as the Quill Gordons.

Also at the upper Doyles site, lots of large winter stoneflies, Strophopteryx fasciata.  Look in the leaf packs.  I can't swear that the Taeniopteryx burksi/maura large winter stonefies are "gone" (= hatched), but it's been awhile since I've seen them.



Look at the length of those antennae!

Three other things.

1. Perlodid stoneflies, Isoperla namata.  They're all over the place at the moment, and we'll be seeing them in large numbers from now well into April.


2. A less mature H. amplum small minnow mayfly, also a male.  Note how at this stage they seem to have four eyes, two on each side.  These eventually merge forming large red eyes that we see when they're mature.



3. And can I make a report at the moment without a few shots of at least one Uenoid?  Upper Doyles -- the rocks were covered with them: just walk through the stream and look down.  I kept three larvae to check for the species ID.  They were all Neophylax consimilis.  Note the pale orange stripe on the head.





Up to South River on Monday.  Until then, it's back to the clouds and the rain and the snow.  Ugh!