I've fished small felt crab patterns I bought down in Islamorada. Essentially they are small eyes on a hook with rubber legs tied madamX style and a small grizzly hackle 'claw', then a pad of felt is glued on (top in tan).
My experience has been that when fish are tailing in skinny water they are actively feeding and stealth is the biggest factor to success. As of this writing I've only done 10 bonefish trips but it seems any decent fly placed correctly without detection gets eaten.
Your question gets me all fired up - I love pursuit of tailing bonefish like few things in fishing. I've literally have laid on my stomach on marl mounds to get my profile down and cast more tenderly than in any spring creek to place a weightless fly (like the one Adrian gave me) in their lane of advancement with great success when the presentation is right.
As the light fades on the flat, I found light colored flies less effective and a dark colored fly (with more contrast at least) fared much better so it pays to have more than one.
I can't wait to see silver tails waving in the low angle light again!
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