Thanks to a bit of Googling, a bunch of old posts with some speculation and photo links that are long broken, along with a single post from James Fatheree on RC where he stated Anchistus miersi. At first glance, I don't see any photos, but one could probably locate some in the scientific literature.
As an edit that may help future searches, commensal shrimp, giant clam, tridacna clam.