clam, scallop, alien?

[wader]

This was found off Kona, I believe I was at 2-step, around 30' water. 12-15 inches in diameter.

Are the orange thingies part of this or are they just hanging out by it? There were 2 of these about 20 feet apart, but this was the better picture.

 

[RussWalters]

They look like some sort of oyster. The orange thing on top is s small sponge.

 

[smellzlikefish]

I believe that's a black-lipped Pearl Oyster (Pinctada margaritifera)

 

[wader]

I didn't know oysters got that big! I guess i missed out on a huge pearl