How to choose a healthy Crocea

[kevensquint]

I would prefer to try an easier clam as my first but around here, anything other than Crocea is hard to find. There is one in particular that I am looking at. The mouth is neither wide open nor closed, its mantle is clean and full, actually I don't know if this is good or bad, but the mantle is very big or extended. Its a clam thats about 5" long and the mantle extends out about 2 1/2" on each side. If thats ok, what else should I look for?

 

[Electrobes]

A couple of things.. I think I wrote something about it on my website - click the red house thingie.

Over extension of the clam's mantles means a lack of light. By what you say, I do not believe the clam you are looking at has this problem.
The wave and watching its reaction helps... if it does not react quickly but sluggishly then I would stay away from it.
Look at its shell closely on both sides. If you see dents or like the shell has been chipped away in a spot avoid it too as it could mean a number of things.
You don't want translucent spots on the mantle as it could mean a burn or lack of zooanthilae.
Look under the clam for the byssal opening. On croceas its hard to miss, with them having the largest one in porportion to their size. With the crocea that size it may be missing, but you are looking for any pyram snails or any other parasites. If it it just rubble from the substrate then it is fine. But if it does have a parasite than leave it be.
Um.. I got interuppted and forgot what else I was going to say.. but the above is a good gist.... have fun