:?: I have used the search feature to no avail in my quest for a recipe for a mahogany dun. Can someone aid in my search? A step by step tutorial would also be helpful. Thanks in advance for any assistance that you can give me. Jim
From Hatches II:
Wings, tails and hackle should be dark grey with a dark brown or mahagony body on a size 8 or 10 hook. One way to tie it would be to use dark moose mane for the tails which are allways hard to find big enough hadkle for on big dries. Make a small ball of dubbing ( brown rabbit?) and divide them with a couple of fibers on each side. From there on you can tie it just like an adams with brown dubbing and dun hackle tip wings and dun hackle.
8 to 10 hook? That must be refering to a different bug than I’m used to calling a mahogany dun. I think of the paraleptoplebia and it’s more like a 14 to 16. Since your in WA I would assume that’s what your looking for. I would tie your favorite style dun (parachute, comparadun, thorax…) with a brown body and a light dun wing.
Rainbow, thanks but I think Jay has it .
Jay, if I understand it is sort of like a BWO but with a brown body. Am I correct on that? Or, are the hackle tip wings a necessary part of the fly form a catching fish equation. You were dead on with the size.
Jim
:oops: That’s why Caucci and Nastasi favor latin names for insects. I just looked up mahogony dun in their index and found only two eastern/midwestern mayflies in the Isonychia genus covered by the same pattern that share that name.
Yes, as much as I butcher the pronunciations, the latin names do cut down on east/west confusion. 
They hatch in spring and fall. I fished a hatch of them a couple of weeks ago. I used a brown parachute with a light dun turkey flat wing. I think my fly was a little too dark in the body, but worked OK.
In Western Mayfly Hatches, Hafele & Hughes list the following Dun characteristics:
wings light smokey-gray
body light blue dun to deep reddish brown
body length 6 - 12mm (1/4 - 1/2 in.)
plus some other stuff about the wings and tails.
They list four patterns for the dun stage, Red Quill, Blue Quill, Mahogany Sparkle Dun and Mahogany Thorax Dun, all in sizes 12 - 18.
Good luck.
I prefer quigley cripple when mahogany duns are emerging. For an adult you can use something like a parachute adams that is brown, or if they’re a little bigger, an extended body drake.
My pattern for this hatch is as follows.
Hook size 14 dry fly
tail: pheasant tail
wing: deer hair
body: pheasant tail, tied like a pheasant tail nymph
This is basically a pheasant tail comparadun. Pheasant tail is extactly the right color for the mahogany dun here in Montana. This is a super easy fly to tie, 2 materials. If you can tie a pheasant tail nymph and a comparadun you can tie this fly. It works great too. If you want to make it more complicated use microfibbets for the tail.
Hey, Ron that is just great. I will try it here in Washington on The Yakima. Thanks. Jim
Mahogany dun here in the east is an isonychia dun … or the smaller being a paralept the larger tied on a size 8 or 12 the smaller 14-16.Dark dun for wing post, mahogany dubbing ribbed with brown floss ,dun tail, hackled with dark barred ginger, tied with burnt orange thread…