What's hiding between my clams?

Fire shrimp aka blood shrimp are reef safe.
I have two of them in my 120 w/ 6 clams and dont seem to bother them.
Very nice clams and the fire shrimp is a beauty too!
Okay, lets see if I have learned anything about the ID'ing of clams. The one on the right is a crocrea and the one on the left is a maxima. Right?

Well, even if I'm wrong, I really like the coloring of both, but I really, really like the one on the right!:D