Another hitchhiker anemone and clam-like organism

[muntwo]

Didn't want steal the last guy's thread on hitchhiker anemone, so I started a new one. This hitchhiker is only about 1 cm in diameter and looks kinda like a rock anemone. Any thoughts?

Also, there is a shell above the anemone in the photo that looks like it is part of the live rock, but there is something living inside... it opens just a crack periodically and closes when I touch it. The odd part is that it opens toward the rock, as opposed to toward open water.

 

[muntwo]

see photo

 

[Herbie]

I'd say the clam is a Brachiopod:
"Brachiopods: HARMLESS
Hard to find an ID on these, but they look like little clams (rounded edges sometimes rippled) imbedded in your rocks. They are bivalves and are on a hinge and look similar to clams, and mussels. They are filter feeders."

I don't know anemones, but it sort of looks like "Aptasia & Mejano: HARMFUL
These are a big time PITA. They move around pop up out of nowhere. They can sting corals and if big enough eat small gobies and such. There are different kinds and colors, and all hard to kill. Aptasia are stronger than Mejanos but still can harm corals. Some people like Mejanos lol and actually buy them… they are kinda pretty lol."
http://www.nano-reef.com/forums/index.php?showtopic=132956

 

[muntwo]

Oh cool, thanks! Good link! Looks like it could be a mejano and I do like how it looks. If it starts spreading like common aiptasia, I'll use aiptasia-x on it.