Murph.
Teal flank feather is a favourite of mine for wet flies on the Irish loughs tied as a full colar and dyed different colours, claret and golden olive (Irish) being the best, as it is a soft feathef it envolopes the wet fly as it is stripped.
But it could be used as a wing post or managed as a Mayfly wing also. It is also good tail material on dabblers.
Goose biot, used as body on very small dry flies, is the best i can think off as turkey biots are used for same. Or white biot used as midge wings tied in lying close to the body.
Regards
Dave