Tuesday, May 24, 2016

Some awesome photos today: back to Sugar Hollow

Tough to know where to begin today: we found some beautiful insects.

Above, our as yet unidentified species of Isoperla ("stripetail") .  Consequently,  Beaty et.al. have it labelled Isoperla sp. VA.  As I noted last time, we're on the lookout for some nymphs that are fully mature, nymphs we can rear to point that they hatch.  This one's not quite there, but the "tan" wingpads are one instar before they turn black.  So I kept him just in case I get lucky.

The stream that we went to today -- the little gem where my friend lives -- was loaded with them.  I took two nets and had 10-12 in my tray.  Have to look next week for some that are fully mature.

And then we have the Leucrocutas.  What a gorgeous insect.  Pretty sure this is L. juno, but as you'll remember, entomologists want to hold off on species ID until more work has been done.  In any event, they too were abundant today.  I took photos of this mature nymph and one that's still sort of young.


Finally, a young Stenacron nymph.  You might recall that the distinguishing feature of Stenacron nymphs is the shape of the gills: they come to a point.

Beaty: "Abdominal gills 1-6 with apex pointed, seventh gill filamentous; three caudal filaments." ("The Ephemeroptera of North Carolina," p. 22)

This nymph is Stenacron carolina, and the key thing to examine is the pale spot on the head.  "S. carolina -- nymphs 10-13 mm; length of pale triangular spot anterior to median ocellus approximately 2X it's basal width (provisional) ...dorsum of abdomen grey-brown without conspicuous markings; caudal filaments all light grey brown with no banding.  Usually in small mountain streams.  Collected spring to summer.  Uncommon." (p. 22)

You can see that "pale triangular spot" very well on almost all of my photos.

And here's a microscope view.


So satisfying to find some good insects and get decent photos.  Up to the Rapidan River tomorrow.

Oh, by the way.  Steve Beaty joined us at this stream last month.  That's him on the right.

No comments:

Post a Comment