Magically Appearing Crab ID?

[Jeremy Snyder]

OK I haven't added any rock or anything in like 6 months. Just some Gulf Pipefish and Feeder Shrimp. None of which contained a "visible" crab. Upon looking in my tank this magically appearing crab showed up. Where it came from, no clue? Can anyone tell me what kind of crab it is?

 

[Peter T]

It looks similar to an acropora crab. Do you have any acropora in there?

 

[Jeremy Snyder]

nope, zoanthids, mushrooms, trumpets

 

[BEASTIEPENDENT]

Hi Jeremy,

that is really an unusal crab You found. To be honest I can't sort it in right now. I thought of maybe Pinnotheridae, the Pea Crabs, but it doesn't fit either. Until now it surely has hidden, that for certain is NOT unusual.

 

[Jeremy Snyder]

Its has kind of a cube body. Its eyes are on the front face, and are not pertruding. EXTREMELY slow, was easy to catch (now isolated). The rim of the shell is raised along with like a raised mohawk. Above his eyes are two raise shell areas. He's like a transparent white except for the pink markings.

 

[Peter T]

Hmm..acro crabs have eyes that protrude on eye stalks. This is a pic of a pea crab I pulled out of an oyster awhile back. It is transparent, just looks dark in the pic. What you describe sounds like a pea crab (behavior and all), but the shape is a just little off. Eye structure almost the same. Except for instead of two raised areas above the eye, it was two whiskers (you can see it in the pic). I honestly have no idea though lol

 

[Jeremy Snyder]

According to this site it is a pea crab. Picture is like perfect:
http://www.chucksaddiction.com/hitchcrabs.html
Reefsafe? I just lost recently a flame scallop, after reading pea crabs, It makes sense.

 

[Peter T]

It does look like the one on that site. I guess there are many different species of pea crabs. I kept mine after taking it out of the oyster for mantis food. It kept on crawling on all my corals blindly ( it reacted to no visual stimuli) and aggravating them before the mantis finally decided to eat him. Glad you got a PID!

 

[Jeremy Snyder]

I think since hes soooo slow and easy to catch, I'll put him back in tank and watch. My pistol shrimp will probably use him for target practice anyhow! HAHAHa

 

[LeslieH]

It is a pinnotheridae & quite possibly the same species in the genus Durckheimia as on Chuck's website. There are 3 or 4 species in the genus. They are internal commensals of bivalves, not parasites, and don't really harm their hosts. I feel sorry for the little guy, after all, he/she just lost his/her home.

 

[Jeremy Snyder]

UPDATE: Pea crab is doing excellent in my dwarf seahorse tank. It has no predators and scares away my dwarves long before he gets close to them. The best part is, he is ALWAYS eating red slime algae. I actually have thought about trying to find another.