Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
This specimen appears to be of the same species as this one collected in the same spot two months earlier. The identification of both is tentative. This one suffered some physical damage before being photographed, too, so the colors aren't totally natural. I was mostly photographing it to test out some new camera setting idea, which worked really well for a couple of closeups.
CalebBoyle on Mar 30, 2007March 30th, 2007, 2:53 pm EDT
Hello all,
This is my first time posting and I must agree with everyoen, this is the best aquatic entomology site by far for the flyfisherman. I have a mayfly hatch from my aquarium that is quite unique in its coloration. I'm pretty sure its a maccaffertium species, but I'm not sure which one. Anyone have some ideas?
Konchu on Mar 30, 2007March 30th, 2007, 3:01 pm EDT
or Stenacron??? I just moved and all my notes/books are tucked away in boxes, but that is my initial guess based on your photos. Nice pictures, by the way.
CalebBoyle on Mar 30, 2007March 30th, 2007, 3:07 pm EDT
It Could be. Is there a good key to look for in the s to seperate the stenacron and Macc? The only thing I can find in my book by Cormier and Knopp, is the shape of the gills.
Troutnut on Mar 30, 2007March 30th, 2007, 3:16 pm EDT
I think that prominent black spot on the wing means it's Stenacron.
I have no clue how to tell one Stenacron species from another, but the one most commonly referenced is Stenacron interpunctatum, so that's as good a guess as any.
Jason Neuswanger, Ph.D.
Troutnut and salmonid ecologist
GONZO on Mar 31, 2007March 31st, 2007, 6:53 am EDT
CalebBoyle-
Beautiful female dun--nice photos. The dark area in the third space on the wing (between R1 and R2) is usually a good character for distinguishing between Stenacron and Maccaffertium or Stenonema adults. It is expressed either as a black dot, as in your specimen, or, more commonly, as a dark patch that connects or nearly connects two or three crossveins.
Distinguishing the Stenacron species as adults is pretty tough and usually requires a male specimen (for penes differentiation) or rearing adults from identified larvae. This specimen lacks the dark spiracular marks (spiracles are the little breathing holes along the abdomen) and the dark streak below the wing base that one often sees on Stenacron interpunctatum. But, as far as I know, these may not be definitive characters.