What kind of crab is this and why doesn’t he move?

[bensoo00]

Just dropped him in after acclimation, a friend gave him to me after breaking down his tank. He hasn’t moved all day and I am unsure how to take care of him because my friend doesn’t know what he is either so I think he bought him on a whim. Anything helps, thanks. He’s in a 50 gallon with medium flow in that spot and his tanks mates are a spotfin butterfly, 2 ocelaris, diamond watchman, skunk cleaner, coral banded shrimp, and long nose hawk fish.

 

[old salt reefer]

Bet he moves tonight when the lights go out.

 

[Reefing102]

I believe that’s a Strawberry Crab. I don’t have much on the care but they may need a dry area (I could be wrong).

 

[EeyoreIsMySpiritAnimal]

Bet he moves tonight when the lights go out.

Yeah, he's probably in survival mode, trying to not get noticed by any predators by moving.

 

[bensoo00]

I believe that’s a Strawberry Crab. I don’t have much on the care but they may need a dry area (I could be wrong).

I see. Do you think that this would be a problem then if he has no land? I could try making something but it’s kinda hard with the way my tank is.

 

[fishywishy]

I believe that’s a Strawberry Crab. I don’t have much on the care but they may need a dry area (I could be wrong).

Strawberry crabs are different. That isn’t a strawberry crab

 

[Stomatopods17]

That's uca. species. Fiddler Crab.

Its probably already dead, they need to surface for air. Some sites sell them as red burrowing crabs.

 

[bensoo00]

Bet he moves tonight when the lights go out.

Yep, he’s an enigma. I’ll walk around and he’ll just be in some random spot on a rock staring at god knows what. I still wonder what type of crab he is but if he’s ok then all is well I suppose!

 

[littlefoxx]

That's uca. species. Fiddler Crab.

Its probably already dead, they need to surface for air. Some sites sell them as red burrowing crabs.

Do they have a good survival rate in captivity?

 

[blaxsun]

You could gently try prodding him with a feeder, stick, etc.

 

[Reefering1]

You could gently try prodding him with a feeder, stick, etc.

My kind of answer right there. "Poke him with a stick"!!

 

[ISpeakForTheSeas]

Do they have a good survival rate in captivity?

Considering that fiddler crabs are semi-terrestrial, they have bad survival rates in traditional aquaria; but this crab isn't a fiddler crab (or a strawberry crab).

Unfortunately, I don't know exactly what species this is, but - going by body shape and the eyes - it's most likely either a Grapsoidean crab (taxonomic superfamily Grapsoidea) from either the Grapsidae family or the Sesarmidae family, or it's a Macrophthalimid crab (taxonomic family Macrophthalimidae).

Either way, there's a good chance that this crab is terrestrial or semi-terrestrial, so prodding it with a stick and trying to check if it's actually still alive is a good idea.

 

[bensoo00]

Considering that fiddler crabs are semi-terrestrial, they have bad survival rates in traditional aquaria; but this crab isn't a fiddler crab (or a strawberry crab).

Unfortunately, I don't know exactly what species this is, but - going by body shape and the eyes - it's most likely either a Grapsoidean crab (taxonomic superfamily Grapsoidea) from either the Grapsidae family or the Sesarmidae family, or it's a Macrophthalimid crab (taxonomic family Macrophthalimidae).

Either way, there's a good chance that this crab is terrestrial or semi-terrestrial, so prodding it with a stick and trying to check if it's actually still alive is a good idea.

Yeah he move around and is still alive. I’m just gonna try and feed him, does he still need dry land or is he good underwater?

 

[ISpeakForTheSeas]

Yeah he move around and is still alive. I’m just gonna try and feed him, does he still need dry land or is he good underwater?

If they're still alive and moving at this point, then they are either semi-terrestrial or a marine species rather than a terrestrial one; if that's the case, then they may be alright under water long term, but if they're a semi-terrestrial species, then they may need access to dry land as well.

Personally, I'd say (if you can with your setup) to provide it some sand to burrow in/walk on just above or right at the waterline for the tank so that it can pop in and out of the sand if it wants to, but it may be unnecessary.