Clam Tumor


New member
I noticed a large 3x3cm mass adjacent to the incurrent siphon of one of my large(~10") derasa. The clam is wild harvested and otherwise healthy. It did have parasitic snails on arrival 2 months ago which were removed. These large clams have somewhat recessed viscera in comparison to my other smaller clams. This mass is definately not byssal gland or adductor muscle which can be seen further posterior when looking thru the siphon. It is smooth. No evidence of boring sponge or algae. Any thoughts? Adam

Sorry, couldn't resist throwing in the Arnold quote. (Vote for him by the way)

I'm not sure what that is as I've never seen that in a clam. Very interesting though. If the clam is healthy and kickin I wouldn't think twice about it.
I agree- I was thinking more of a symbiot that had encapsulated in the clam shell wall-not harmful to have gotten that large so far.
I wonder if Firechild may have some thoughts-Adam
I've been noticing something similar in one of my clams recently. Does it look like this:
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I thought it was the adductor muscle swollen but I'm really not sure.
Susan-I remenber your post and that pic-I don't think it's the same. This is definately distinct from the adductor and other viscera.
No I meant giant clam. Like an oyster when foreign material becomes trapped inside the shell the clam responds to the irritation by producing a nacre. This is a combination of calcium and protein. Which over time is a pearl.
The LARGEST pearl ever found is 14 pounds! 9.5 inches by 5.5 inches. Found in 1934 in a giant clam in the Phillippines.
This mass is pearly white and anterior. It's not anywhere near the byssus. I like the 'pearl' theory!
Yep, so was the one mine expelled. Part was pure white. I do not pretend to understand the internal structure of a clam, but there must be enough room or open cavity that connects the two areas. Give it time and I suspect it too will expel this tumor.