Mahogany Dun
Imitates: Adult Paraleptophlebia mayfly (Mahogany Dun)
Quick Reference
- Best Sizes
- #16-18
- Best Season
- September through October (peak fall hatch)
- Best Conditions
- Cloudy fall afternoons, slow tailouts, mixed BWO hatches
- Water Temp
- 48-58°F
- Recommended Tippet
- 5X-6X mono
How to Rig It
Single dry on a 12 ft leader for spooky fall fish. Trail a small BWO emerger 14" behind during mixed hatches.
How to Present It
Dead-drift through soft seams and back eddies. Fall fish are leader-shy and eat slowly — long natural drifts beat short aggressive ones.
Why It Works
Mahogany Duns are the signature fall mayfly across the West and East — reddish-brown body, dark dun wings, hatching alongside BWOs on cool overcast afternoons. Trout are bulking up before winter and eat them deliberately on top.
History
Recognized as a distinct mayfly hatch by Western anglers in the 1970s. The pattern became standard on rivers like the Bighorn, Missouri, and Madison once tiers stopped lumping fall mayflies together as 'BWOs.'
Pro Tip
If BWOs are hatching but fish are refusing your size 20 BWO, try a #16 Mahogany Dun on the same leader. Often the bigger Mahogany is what they're keying on, even when smaller BWOs are also on the water.
Frequently Asked Questions
What is a Mahogany Dun?+
A Paraleptophlebia mayfly — reddish-brown body, dark dun wings, size 16-18. The signature fall mayfly hatch on Western and Eastern trout rivers.
When does the Mahogany Dun hatch?+
Mid-September through October on cool overcast afternoons. Often overlaps with fall BWO hatches but emerges in slightly slower water.
Not sure if Mahogany Dun is right today?
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