well megadon, im pretty sure that its not anemonia majano. to tell you the truth it looks more like a corallimorpharia, of the genus corynactis, or possibly Pseudocorynactis. these guys are fairly small, an dare often light red, brown or white, and do have very powerful stinging cell, although they arent harmful to us. to tell you the truth i think its one fo these guys, but who knows. how big is it? i would leave it in there if i were you. i just dotn think its a majano anemone, cause i have these all over in my 135 and i have a ton of shrimp in there as well, and they have never gotten a shrimp!
good luck
jon