Saturday, June 1, 2013

Rapidan River, Pt. I.: everything "but" the Isoperla orata

I have no doubt that I found Isoperla orata -- Perlodid stonefly -- this morning at the Rapidan River.  Actually, I saw 4-5 of the nymphs.  But in this entry let me post photos of everything else that I found: I want to make the full case for the I. orata ID in a separate entry using Beaty and Frison (the entomologist who first described this as a new species).

1. Limnephilidae (Northern case-makers), Pycnopsyche scabripennisis (TV, 2.5).  I was expecting to see them, and I found three.  I was hoping for more elaborate cases, but we take what we can get.  The two in the photos below both constructed the "hot dog" case -- two long twigs on the sides, filled in with bits of wood and bark.  (The I. orata nymph on the back of the case is 8 mm which will give you some sense of the size of the case.)



2. A very nice, very large Epeorus vitreus flatheaded mayfly.  Here as elsewhere they were all over the bottoms of rocks.  Like the orange color.

3.  Spiny crawler mayfly, E. dorothea.  Still a lot of them at the Rapidan river in clumps of twigs, roots and leaves.

4. Perlodid stoneflies - Isoperla holochlora.  The bug of the day without any doubt.  They were simply all over the place.

5. And a common netspinner caddisfly larva, Ceratopsyche slossonae, tolerance value, 0.0.  This is the one that has the single pale dot in the middle of its head -- well, face.


Now, full attention tomorrow (Part II.) on our new addition to the EPT list, Isoperla orata.

1 comment:

  1. Hope you don't stop writing your blog any time soon. To me it's so interesting. I look forward to it.

    I was wondering something. You show lots of photos of Isoperla. I've looked at these stream's insects alot more in the adult stage than the nymph. Is this Isoperla the little yellow stone fly I see? I've also seen a little green stonefly about the same size. Chloroperla? Thanks again for your good work.