Clam ID

[jimmy 4]

Im not even sure if this is a clam. I bought some zoas and realized that they were on a clam after I put it in the tank. I removed the zoas. Should I keep this guy? My tank is only 20 gallons.
also the little white bump on the top left of it opens up as well. What is it, another "clam"?

 

[renogaw]

probably some cleaner clams. keep em. i had one pretty big one for a few years until it died...boy did my clean up crew have a feast!!