I just acquired my very first clam from someone tearing down their tank. I am assuming this is a squamosa. It is approx 10” in length. Small football size. Why does the mantle and incurrent siphon on this clam not look like any I am seeing online. I will post a pic in his tank first then one in mine. I’ve read about PMD but dosent look to me that this is what it is. Thanks in advance