ID crab found on acropora coral

[Poorcollegereef]

Hey, I need some help IDing this crab that piggied backed on a acropora that I bought a couple of days ago. The picture isnt that good but the crab is about 1/4-1/2 inches wide, very thin, pink/flesh tone in color, has a dark band running from eye to eye, it has a small dark dot on each of his jointed legs, his claws are long and narrow-the pinchers are small but the arm is nearly as long as his body. I have not seen it move from the coral since I bought it. Im not in a rush to remove it unless it damages my acropora because it isnt very large. It is smaller than a few zebra dwzrf hermits that I have. Thanks for your help

http://reefcentral.com/gallery/showphoto.php?photo=155833&papass=&sort=1&size=medium&thecat=

if the image doesnt pop up, here is a link http://reefcentral.com/gallery/showphoto.php?photo=155833&papass=&sort=1&size=medium&thecat=

[The steven liu]

picture is too blurry and low in resolution, please provide a better picture so we can see. Thanks

[LeslieH]

Reefcentral isn´t letting me see your picture but from your description I´m pretty sure it´s a Tetralia or a Quadrella. Both of them are known as acropora crabs because they´re always associated with acropora. They mainly live on the mucus produced by the corals although they will occasionally eat polyps, they also help defend the coral against other predators.