These nymphs are really cool. I remember that their "gait" (if you can say a bug has a gait) seems as though they've got just a little bit of walking stick in them.
Gonzo had some good information on these
in another thread.
All the other information I've found on this species from an angling standpoint is on my
E. septentrionalis page, and it's not much at all. It sounds like they just blend in with the other
Ephemerella sulphur hatches and most people don't notice a few goofy, gangly ones amidst thousands of near-identical
invarias.
I have been meaning to send Jason a note asking him on how accurate is the color of the naturals he photographs to their true color? Are these their true colors or is something lost in translation?
It's usually pretty accurate, especially in the pictures from 2005 or later. I shoot a lot of pictures (including this nymph) against a white background or with some white object in the frame. If the white thing actually looks white or neutral gray (without some colored tint) you can assume the bug's colors are pretty accurate, too. The main thing to account for is that there's some translucency in a lot of them, especially in the thin parts like legs. When you see the very light olive legs on this nymph, be aware that they'd look pretty different against a dark background.
Also, there's a lot of natural variation in the colors of many nymphs, especially in
Ephemerella. Several species come in a wide range of olives and browns in the same stretch of the same stream. I didn't capture enough
septentrionalis nymphs to show that, but it's evident in my
invaria and
subvaria specimens and you could probably expect it for these, too.
Long store short: A PT nymph would probably do it.