What is this on my clam??

[livinlifeinBKK]

Hey guys, I noticed a strange yellowish growth on my usually happy clam and I'm concerned about what it may be. It seems to be attached to the shell and not flesh but it certainly hasn't been there for long. He has been acting normal with the exception of drawing his mantle in a little more than usual for short periods of time. This has only been going on maybe a week. Here are some pics... Any help is appreciated!

 

[Ricksreeefs]

Looks like a big pineapple sponge to me. Not sure though bummmpp!

 

[livinlifeinBKK]

Looks like a big pineapple sponge to me. Not sure though bummmpp!

I don't mind it naturally growing there if it's natural and harmless...I just want to make sure its not some type of parasite

 

[Bfragale]

+1- Look like a sponge to me. My clam grows sponge as well. Should be harmless

 

[G Santana]

Agreed on sponge!