I had recently purchased this incredible and healthy looking Teardrop Maxima from a friend of mine at a LFS here in Columbia. It was an incredible clam with a good healthy-looking byssal opening with no visible defects. Here is one of the last pics I got of it:
The only thing I noticed was that for a clam that large, it really did not open the mantle very wide. I had the clam for about 3 weeks, and it appeared healthy for the most part. It was very responsive to shadows and to the cycle of the 250-watt Metal halides and actinic dusk/ dawn. As I mentioned, the byssal tissue appeared undamaged and healthy- something to always look for when selecting clams.
The other night I noticed that the clam did not open much at all, and that the incurrent siphon was limp all around the edge so that instead of a frilly-edged opening it was a big round gape. I also noticed the peppermint shrimp getting excited about the clam and sniffing around it. (They never have bothered any of my healthy clams.)
The next day the clam was dead. Of course, being the reefer I am, I had to open it up and try to decipher what went wrong. (the other dozen clams are all perfectly healthy)
Upon opening the clam, I found a very large (1"-1.5"), jagged piece of liverock INSIDE the clam. See this pic:
My opinion is that the clam was broken off of a piece of live rock, at which time it pulled all the byssal cords into the open hole around the damaged base- pulling this hunk of jagged rock into the shell itself through the damaged byssal opening.
The clam had completely healed AROUND the rock. There was no visible sign of anything but healthy tissue from the outside. My guess is that eventually there was internal damage as the clam tried to expand the mantle fully or close the shell.
After gawking at this a minute, I noticed a movement in the other half of the shell.
There were two shrimp living INSIDE the clam! They are mostly translucent, with dark spots visible on them. I was able to capture both shrimp alive and I still have them available to study and photograph. I had heard of commensal shrimp living in large Tridacna clams, but this is the fist time I have seen pictures. Here they are:
I sent a message to Dr. Ron, who agrees that these are commensal shrimp that live in the clams peacefully. He believes that they feed on mucous that healthy clams slough off when feeding. I thought this was so cool to be able to photograph them. They were shot above in a white bowl so that their transparancy would not prevent you from seeing them.
Just a few moments ago, I read a post by a friend of mine, Minh Nguyen discussing problems with the collection of these teardrop clams.
Here is a link to the post : http://reefs.org/phpBB2/viewtopic.php?t=23356
Poor collection methods could certainly explain why my clam had a large hunk of rock deep inside that it had healed over, although I suppose it could have happened naturally also. Sorry for the long post, but I found this all very interesting.
(although sad)
The only thing I noticed was that for a clam that large, it really did not open the mantle very wide. I had the clam for about 3 weeks, and it appeared healthy for the most part. It was very responsive to shadows and to the cycle of the 250-watt Metal halides and actinic dusk/ dawn. As I mentioned, the byssal tissue appeared undamaged and healthy- something to always look for when selecting clams.
The other night I noticed that the clam did not open much at all, and that the incurrent siphon was limp all around the edge so that instead of a frilly-edged opening it was a big round gape. I also noticed the peppermint shrimp getting excited about the clam and sniffing around it. (They never have bothered any of my healthy clams.)
The next day the clam was dead. Of course, being the reefer I am, I had to open it up and try to decipher what went wrong. (the other dozen clams are all perfectly healthy)
Upon opening the clam, I found a very large (1"-1.5"), jagged piece of liverock INSIDE the clam. See this pic:
My opinion is that the clam was broken off of a piece of live rock, at which time it pulled all the byssal cords into the open hole around the damaged base- pulling this hunk of jagged rock into the shell itself through the damaged byssal opening.
The clam had completely healed AROUND the rock. There was no visible sign of anything but healthy tissue from the outside. My guess is that eventually there was internal damage as the clam tried to expand the mantle fully or close the shell.
After gawking at this a minute, I noticed a movement in the other half of the shell.

There were two shrimp living INSIDE the clam! They are mostly translucent, with dark spots visible on them. I was able to capture both shrimp alive and I still have them available to study and photograph. I had heard of commensal shrimp living in large Tridacna clams, but this is the fist time I have seen pictures. Here they are:

I sent a message to Dr. Ron, who agrees that these are commensal shrimp that live in the clams peacefully. He believes that they feed on mucous that healthy clams slough off when feeding. I thought this was so cool to be able to photograph them. They were shot above in a white bowl so that their transparancy would not prevent you from seeing them.
Just a few moments ago, I read a post by a friend of mine, Minh Nguyen discussing problems with the collection of these teardrop clams.
Here is a link to the post : http://reefs.org/phpBB2/viewtopic.php?t=23356
Poor collection methods could certainly explain why my clam had a large hunk of rock deep inside that it had healed over, although I suppose it could have happened naturally also. Sorry for the long post, but I found this all very interesting.
(although sad)