Need help identifying hitchikers on LR

[PreetSu]

Im brand new to the hobby and just got part 1 of "thepackage" from tampabaysaltwater.com for my 29 gal tank. Well i have been hearing popping/clicking noises. Upon investigation we found the rock they were coming from (we think)!! Only found some crabs on there. From reading and googling, i was expecting a mantis shrimp. Well havent found him yet. Could it be anything else? Are these crabs reefsafe? Or should i take them to my LFS? Any advice would be greatly appreciated.

 

[Sapelo]

Gorilla crab. Get rid of them.

 

[Ron Reefman]

Gorilla crab. Get rid of them.

I'd have to research to try and figure that out. But I can say for sure those are 2 different crabs.

So which one do you think is a gorilla crab? And what is the other one?

Five minutes later:
And after a little research and discussion with my snorkeling partner, we think the one on the left is a stone crab (bad) because it has the right body shape and the black tips on the claws. The one on the right is a porcelain crab (good). Even with what look like big claws, it's a filter feeder. Just Google the names and look at the pics.

 

[billdogg]

I'd have to research to try and figure that out. But I can say for sure those are 2 different crabs.

So which one do you think is a gorilla crab? And what is the other one?

Five minutes later:
And after a little research and discussion with my snorkeling partner, we think the one on the left is a stone crab (bad) because it has the right body shape and the black tips on the claws. The one on the right is a porcelain crab (good). Even with what look like big claws, it's a filter feeder. Just Google the names and look at the pics.

^^^What he said^^

The stone crab can go in the sump if you are so inclined.

 

[Dogshowgrl]

The one on the right is a nice porcelain crab! People pay good money for them! The other is a stone crab mine go in my mantis shrimp tank but otherwise they can go to the sump! Good luck!

 

[Finland]

The popping/clicking noise can be coming from little pistol shrimp. They range from 1/2-3/4 inch long and can be difficult to spot. When I received my TBS rock, I was amazed how loud the clicking was from such a tiny pistol shrimp. It could be a mantis shrimp also. In your pic, as already stated, the left one is a rock crab(sump time) and the right crab is a porcelain crab(good crab).

 

[PreetSu]

Thanks a lot

Thanks a lot

Thank you for your help. Is my first experience with LR, and hitchikers. I looked at the pics but still couldnt say for sure. You all are life savers!