Lysmata wurdemanni is the correct species, some of the other species are not so nice to coral. There are several "imposters", Rhynchocinetes durbanensis will eat coral if given the chance, but they're actually used to eat flatworms off of Acropora and do it very well if applied correctly: http://www.korallen-zucht.de/index.p..._id=52&clang=1
More info on other "imposters": http://fish.suite101.com/article.cfm...rimp_imposters
FWIW, I have spotted several different species of these guys being sold as "peppermint shrimp" at LFS in our area Rob.