Found this urchin i believe it to be Echinometra mathaei oblonga

[Poseidon Johnson]

Is this a rock boring urchin and is it safe or poisonous?

 

[Poseidon Johnson]

So far in this live rock I've found a lime green mantis shrimp, a red emerald crab I think it's a Helmet crab and this fuzzy death spike urchin thing.

 

[Poseidon Johnson]

Here's the crab

 

[Poseidon Johnson]

 

[Poseidon Johnson]

I believe these to be feather duster worms.

 

[Poseidon Johnson]

This is the best shot I could get of the slippery little mantis shrimp

 

[kjkszpj9]

crab looks like a red mithrax crab

 

[Poseidon Johnson]

crab looks like a red mithrax crab

I think you're right. Thanks