2012/4/3 CDC Peacock Beetle
In summer time, mountain stream in Japan become quite simple once insects fallen from trees become abundant. Very simple and effective pattern that should stay in your fly box especially when you go after chars.
You could wrap a hackle in parachute style to improve buoyancy, but that will make the profile larger and tends to turn off cherry salmons who love think shape object.
Hook: Gamaktasu C14-BV (eye opens sideways) #12-18
Wing: CDC natural colour
Under Body: Dark coloured dubbing
Over Body: Peacock herl (use 3 or more strands to make fat body)