mayfly id

Discussion in 'Fly Fishing Entomology' started by triploidjunkie, Aug 21, 2012.

  1. This guy fluttered onto the job site near the river. Crappy pic but I thought someone may have some idea. Yellow body with blue eyes. At least size fourteen

    Attached Files:

  2. I would guess PMD. Could be a PED though.
  3. hi triploidjunkie-

    Have cropped and rotated your photo so it can be more easily seen:

    This male subimago is of genus Maccaffertium, and would be called a Light Cahill.
  4. Thanks taxon. All I have is my phone, so fixing the pics wasn't easy for me. Are those cahills common in wa? I thought they were further east.
  5. hi triploidjunkie-

    No, they are uncommon in WA. The only one (of which I am aware having been officially recorded) in WA is Maccaffertium terminatum, records of which are as follows:

  6. I was working beside the okanogan river. Saw a few of them last week. Only one held still for a pic. I was thinking some kind of sulfur but thought it was an east coast species.
  7. hi triploidjunkie-

    Mayflies of genus Maccaffertium are mostly found in the eastern half of the US. Please see the this distribution map, which is available on BugGuide:

  8. Out of curiosity, what do you make of these. They were all take in SE Washington, which fits with your "official" recording. I've clumped them by what I think are the species, but I'm not sure. The first group (1-4) all have large, brown eyes (male?), three striped tails. The next (5-9) looks a lot like the cahill posted above, but 3 tails, and I assume #5 is a spinner of same?;

    The last two... Light wings--#10 is very yellow winged--but olive body, not eyes like the others (is that just male/female?). But it seems that #10 might have three tails, and #11 only has two.I'm not seeing the small wing on #11, but it looks like it might be there only damaged/crumpled of. But if I remember correctly, at the time I wasn't thinking it was small like a BWO. (I should have taken notes. Back then I was more intrigued by their beauty and trying to get photos than I was of their taxonomy.) And looking at it now--though w/o scale--it's body doesn't seem BWO slender to me.

    #12 appears to be the same blue-eyed bug posted above, but I'm noticing it has two long tails. Longer than the the other yellow/pink/orangy bugs it seems, and only two of them.

    These were all taken on the same day in 2009, late may. The very last pic was taken almost 3 years later to the day.

    Three tails means crawler? Two means clinger or swimmer?

    Attached Files:

  9. hi tkww-

    01 Ephemerella excrucians male subimago
    02 Ephemerella excrucians male subimago
    03 Ephemerella excrucians male subimago
    04 Ephemerella excrucians male subimago
    05 Ephemerella excrucians female subimago
    06 Epeorus female subimago
    07 Ephemerella excrucians female subimago
    08 Ephemerella excrucians female subimago
    09 Ephemerella excrucians female subimago
    10 Centroptilum female subimago
    11 Epeorus female imago

    For the winged lifestages of mayflies, if one were to ignore the burrowers, that rule of thumb would be correct. However, some burrowers have two tails (Hexagenia and male Ephoron), and some burrowers have three tails (Ephemera, female Ephoron, Anthopotamus, and Pentagenia).
  10. Many thanks!!

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