ID Please

[oh207]

I have several of these in my tank. Some of them are cut in half, but still moving on the class.
What is it and is it reef safe?

Thanks!

 

[cmantis]

Astrea (sp?) Starfish - harlequin shrimp

 

[oh207]

Hi cmantis, I don't have a harlequin shrimp. I do have 3 small peppermint and one fairly large blood shrimp. I also have a lot of hermit crabs and 4 emerald crabs.
Maybe they are nipping at them?
Are they safe? I see them on some of the zoa frags too.