We all see them at the end of the trout season and the beginning of Autumns. In fact they hatch nearly all year round.
I am talking about Needle Flies or Willow Flies as they are sometimes called.
I have been using this pattern pretty successfully. I have experimented with photo colours. Hope you like it.

Hook: Partridge Extreme Klinkhamer Size 20.
Thread: Black Uni Thread 8/0
Bead: Size 3/32 Gold Tungsten (if you look carefully at the middle of the picture you will see one with two blackbeads. This is a heavy version
Tail: 2 Olive Goose biots split by olive dubbling
Body: Virtual Nymph Flexibody strip (1mm) - Olive
Thorax: Olive dubbing
Legs: Olive Goose biots tied a the beginning, the middle and head of the thorax
Wing case: Virtual Nymph Flexibody strip (2mm) - Olive