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3. central penna mayfly nymphs

i am finally figuring out how to use my macro setting.
i seined these in mid may on a spring creek.
after the photo session, i caught a bunch of fish sight nymphing an unweighted biot body nymph that looked something like the larger specimen.
sorry about the palm of my hand, roger. i honestly do keep reminding myself to bring along a white lid. i think i left it in the right front inside pocket of spence's vest, next to the space blanket...

Hey, you are getting there with macro shots!

The larger one looks like Maccaffertium (could be vicarium), it's definitely a clinger. The smaller nymph looks like Ephemerella (could be subvaria).... Hendrickson.

Tony,

I was wondering where that extra lid came from!!! You know I have problems already...Carry your own damn lid! Hell...Now that I think about it, one never knows when an extra lid may come in handy...I think I can squeeze it in...somewhere.

Spence

Hmmm, Tony, I would have thought better of you!

sorry that there is no size reference in the photo. the Ephemerella was around a size 20. my thought was dorothea. the clinger is beyond my limited ability to even guess. what are the common cahill species in this region. plenty of dorothea and invaria hatching and dropping that evening. also a good number of "lt. cahills". could these be ithaca or canadense nymphs?
i'll be without my computer for the next few days - gotta go and chase some Megalops atlanticus, but i look forward to your thoughts.
if i start trying to identify shrimp and crabs down to the genus and species i'll need a psychiatrist (or spence) to help bring me back to sanity...
maybe (hopefully!) some photos to follow

That is my thought as well, though it is impossible to be sure from the photo. (It is a mature nymph--a "blackwing"--and if the "dorothea" that you were seeing had unmarked tails, the ID would seem probable.) I agree with John that the "clinger" is probably Maccaffertium. If you can remember to flip the flattened clingers over and photograph the undersides, the species can often be recognized by the ventral markings. (You can put that reminder on the same list as remembering to retrieve your white lid from Spence's vest, assuming that it can be found amid all the paraphernalia he carries. That man is a human Swiss Army knife!)

What would be other possibilities, out of curiosity? I was pleased with myself that I immediately thought March Brown and subsequently found that that's what you guys meant by Maccaffertium. But in the interest of confusing myself, I'd like to know the other options.

-Shawn

Shawn,

Stenacron, Maccaffertium, and Stenonema (femoratum) nymphs all look pretty similar. All are "flattened clingers" with broad rounded heads, flattened femurs, three tails, and slender (or "threadlike") 7th gills. One way to make sense of the current taxonomic scheme of this group is to remember that the other gills are pointed at the tip in Stenacron, squarish (truncated) at the tip in Maccaffertium, and rounded at the tip in Stenonema (femoratum).

Within Maccaffertium, PA species include vicarium (March Brown/Grey Fox), ithaca (sometimes called a Grey Fox, but also called a Ginger Quill), modestum, mediopunctatum, terminatum, pulchellum, and a few less common species. (Members of the last group are most often referred to as "Light Cahills," but that name is also used for Stenacron species.)

Are you confused yet?

So my little taxonomic scheme of robust PT or slender PT and Big, Medium, little and tiny yellowish white bugs probably wouldn't work?
Just don't tell the trout they eat my big yellowish bugs just fine! ;)
John