I know this fantastic fly from an Italian friend. I use this fly for Winter grayling fishing. It is one of the best dry fly that I use in this period.
Materials:
Hooks: Demmon G900 BL #16-18
Thread: Textreme Pure Silk in olive, light olive, medium olive colors
Wing: CDC Khaki Campbell
Hackle: Whiting Brahma Hackle – one turn
Here are 3 flies for grayling that I use to fish in Central and East Europe:
Orange Neck Pheasant Tail Variant – is popular all European Countries like ( France, Spain, Italy, Czech Republic, Slovak Republic, Poland, Serbia, Croatia, Montenegro and Romania )
Orange Torax Pheasant Tail Variant is popular in Central Eastern Countries ( Czech and Slovack Republics, Poland and Romania )
Back Orange Phasant Tail Variant – is popular in Central Europe and Italy
…and all of them ready for fishing
This fly is one of the best nymph for fishing grayling using french style of nymphing.
For fishing trout I recommend to apply a layer of UV Resin from Deer Creek. In this way the body will be indestructible.
Materials:
Hooks: Maruto Dohitomi D82 BL size #16
Thread: 17/0 Uni Thread
Body: hand cleaned peacock quill -natural color
Tail: nutria guard hair -dark natural
Torax: mad rabbit dubbing in natural and yellow mixed
Legs: hen mottled barbs from Brahma hen
Back: cream and olive body thread from Devaux
happy tying 
Lucian