While traipsing through the local fish stores, we came across a beefy Tridacna squamosa clam and noticed it had another little bivalve attached to the side of its shell. The small hitchhiker appears to be a scallop, and it is tucked away in between some of the lateral scutes on the side of the much larger squammie. This little scallop and other hitchhiking clams are commonly found on imported live rock, corals, and clams. They often go unnoticed because they blend in very well with the rocky substrate, however the hitchhiker shown above stands out like a sore thumb. Fortunately, the scallop can be easily removed without harming the clam.
Picture of the Week, Clam on Clam Action0