Yeah, they are good guys/algae eaters. I think it's the same species that Brian Plankis has been working on ID'ing. Quite a few people seem to have them in their tanks, and they apparently reproduce fairly easily in reef tanks.. but nobody seems to know where they originated. Whichever species it is, it's not one that is well known outside the aquarium hobby. It is probably going to be one of several similar species from the Panamic region/eastern tropical Pacific.
Don