Tail: Mallard, three fibers
Body: Rat’s back fur, mixed with yellow mohair
Hackle: Grey
Wing: Grey mallard
Head: Peacock herl
Grey Drake from The Art of Angling by William Blacker. The one above is tied in hand on a vintage blind-eye hook, while the three below all are tied for fishing on Ahrex FW580 #10.
I have neither mouse or rat in my material-stash, but I chose some grey mole that should be close enough (without me knowing the exact qualities of rat).