crab ID - Page 2

Markarian421 · 05/04/2006, 08:35 PM

Which crab? The black one I have never touched any corals. The other one certainly did.

Our black one is very shy, it never comes out in light and even in the dark stays at the back of rocks or close to them. We tried all kinds of traps with no luck. We finally caught him when we were rearranging part of our tank and had a bunch of bare rocks -- at midnight the other night I saw him on one of those rocks, and my wife pulled the rock out the the tank as I followed with a net, and it dropped off the rock into the net.

If your crab is attacking corals though, no need to be nice unless you really want to. Go after it with an ice pick.

spankey · 05/05/2006, 05:49 AM

Well after doing alot of research. I came to find that this might be an emerald (mythrax) crab that is black. I have seen emeralds in all shades of green to even so dark they look black. This is copyied from "LiveAquaria".....

"The hardy Emerald Mithrax Crab, also known as Emerald Crab or Emerald Mythrax Crab, has a shiny green, flat, compact body and hairy legs.
It requires a mature aquarium with plenty of rock work and hiding places. The Emerald Mithrax Crab eats algae and various types of meaty items it can scavenge. It can be harmful to small fish, but unlike many other animals, it will eat bubble algae and is useful for cleaning tanks of this potential problem. They are an opportunistic feeder, and if food is not available to them, they may turn to supplementing their diet with corals or invertebrates.
If there is insufficient algae, their diet should be supplemented with dried seaweed, chopped meaty items or a quality pellet food. "

I think what this crab is, is just a large long lived emerals crab. Now my only option is how the heck can we catch it????
Thanks
Spankey

spankey · 05/05/2006, 05:53 AM

My crab is the on in the picture that has the hairy legs and is all black. It does have some white in between its joints. Its just like the one from the crab from Melv's page?????
After seeing all types of pics of emeralds, that is exactly what my crab looks like, but black. Could just be a bad coloration. They do claim that they are great for reef tanks when small, but when they get full size, look out!!!

I am in NO way being nice to this crab when I get the chance to get it. Although its not the crabs fault. The thing is, how do I feed this monster, just shove some seaweed between my rocks and pray it finds it before my fish do????
Thanks
Spankey

Eugene Ciccimaro · 05/05/2006, 07:01 AM

In my experience no crab (except hermits) are truly reef safe. Even an emerald may start eating soft coral when hungry. I've seen it with me on eyes. (That last sentence should be read in a pirate voice).

Eugene Ciccimaro · 05/05/2006, 07:02 AM

on=own

Markarian421 · 05/05/2006, 08:43 AM

I used to feed ours by giving it a rolled up piece of nori with tongs. It would come out at feeding time anyway to get food, and became less and less shy. But once fish started to vanish, keeping it well fed with nori didn't seem to matter.

spankey · 05/05/2006, 10:30 PM

Ok,

I got him tonight! The drinking glass trick worked!!!

I took a tall glass and laid it against the rock enough of an angle that it could climb down in and when it did it would slide down to the bottom of the glass and thus not be able to get traction to get back out. At first he was leary, but then fell for it. He it GONE now..

I wrapped some seaweed around a small rock with a rubber band to coax him in..

Thank god this thing is out of there. His coral eating days are over. I actually caught him grab a hermit crab and start to eat the shell around the little hermit..

His claws were longer than his body when stretched in front of him. This is one mean looking dude!!!

Outa here!
Thanks
Spankey

Newflavor · 02/03/2007, 12:24 AM

do you have a pic of thiscrab?

spankey · 02/03/2007, 06:41 AM

No I deleted it some time ago. It was an emerald crab that when in adult stage they get huge and sometimes eventually turn black... If you look at emerald crabs thier claws look scoop like at the tips.. Thats what this was

vangoghfish · 06/15/2007, 11:43 PM

I have one like Dr4g0nf1y's photo of crab in hand, what kind is it, got one as a hitchhiker on a nice piece of live rock I just recently got, preditor, or ok, mine is about 2-1/2", nice size.

Markarian421 · 06/16/2007, 05:02 AM

It's some kind of mithrax. Mine was ok for a long time, a great algae eater, but it eventually started to pick off chromis.

4218kris · 12/18/2007, 08:04 PM

does anyone know what kind of crab this is? [IMG] http://reefcentral.com/gallery/data/...97100_1161.jpg[/IMG]

Dr4g0nf1y · 12/18/2007, 11:30 PM

Start here http://reefkeeping.com/issues/2003-12/rs/index.php

Pay attention to the portion of the article that deals with body shape to identify species.

steel3470 · 05/30/2008, 11:58 AM

im always looking to get those types of crabs for my crab only tank.

Ahall003 · 03/28/2012, 08:56 PM

Can anyone help ID this guy, I found him on st Augustine beach fl, thanks!
http://www.facebook.com/photo.php?fb...5&l=e41817289b

bunzaroo · 03/29/2012, 07:50 PM

Looks like a ghost crab

anaya · 03/29/2012, 08:29 PM

I have two in my tank and I love em! Well mine look identical to them except they are an awesome purple color. I get mine to come out by feeding the rest of my tank first, then I locate them with a flashlight if necessary. After finding them I simply get there attention with a chunk of fish flesh. I usually tease them enough to get them to come out of there hide spot and onto the sand-bed. I would think you could do the same but have a small piece of plexiglass and a net at the ready. Once it is on sand bed keep it distracted with the food, slip the plexi between it and the rocks, blocking his escape route, using the net to scoop it up. Best of luck, try to not kill it if your LFS will take it back. People like me would love to have the little monster.

Antonio

Kazza77 · 07/21/2015, 08:18 AM

I'm just setting up marine after a decade away, this little fella hitchhiked in on my live rock.

The claws on it are telling me he is not a friend?

Any advice on what he is & if I should get him out my tank ASAP ?

Thanks

mina_miyoko · 08/28/2016, 07:41 PM

I found this crab in far rockaway beach, new York beach 67. I was wondering what kind of crab is it?

05/05/2006, 05:49 AM	#27
spankey Registered Member Join Date: Dec 2004 Location: Eastern Pa Posts: 2,671	Well after doing alot of research. I came to find that this might be an emerald (mythrax) crab that is black. I have seen emeralds in all shades of green to even so dark they look black. This is copyied from "LiveAquaria"..... "The hardy Emerald Mithrax Crab, also known as Emerald Crab or Emerald Mythrax Crab, has a shiny green, flat, compact body and hairy legs. It requires a mature aquarium with plenty of rock work and hiding places. The Emerald Mithrax Crab eats algae and various types of meaty items it can scavenge. It can be harmful to small fish, but unlike many other animals, it will eat bubble algae and is useful for cleaning tanks of this potential problem. They are an opportunistic feeder, and if food is not available to them, they may turn to supplementing their diet with corals or invertebrates. If there is insufficient algae, their diet should be supplemented with dried seaweed, chopped meaty items or a quality pellet food. " I think what this crab is, is just a large long lived emerals crab. Now my only option is how the heck can we catch it???? Thanks Spankey __________________ 75RR. 6x54w T5. Vortech, Reef Octopus Recirc Skimmer, RKL Controller.. On a restocking Frenzy ;0

05/05/2006, 05:53 AM	#28
spankey Registered Member Join Date: Dec 2004 Location: Eastern Pa Posts: 2,671	My crab is the on in the picture that has the hairy legs and is all black. It does have some white in between its joints. Its just like the one from the crab from Melv's page????? After seeing all types of pics of emeralds, that is exactly what my crab looks like, but black. Could just be a bad coloration. They do claim that they are great for reef tanks when small, but when they get full size, look out!!! I am in NO way being nice to this crab when I get the chance to get it. Although its not the crabs fault. The thing is, how do I feed this monster, just shove some seaweed between my rocks and pray it finds it before my fish do???? Thanks Spankey __________________ 75RR. 6x54w T5. Vortech, Reef Octopus Recirc Skimmer, RKL Controller.. On a restocking Frenzy ;0

05/05/2006, 07:01 AM	#29
Eugene Ciccimaro Registered Member Join Date: Dec 2004 Location: Outside Phila. Posts: 136	In my experience no crab (except hermits) are truly reef safe. Even an emerald may start eating soft coral when hungry. I've seen it with me on eyes. (That last sentence should be read in a pirate voice). __________________ I think its becoming a mental disorder. Current Tank Info: 50g display, 10g sump, 10g fug, PC orbit

05/05/2006, 07:02 AM	#30
Eugene Ciccimaro Registered Member Join Date: Dec 2004 Location: Outside Phila. Posts: 136	on=own __________________ I think its becoming a mental disorder. Current Tank Info: 50g display, 10g sump, 10g fug, PC orbit

05/05/2006, 10:30 PM	#32
spankey Registered Member Join Date: Dec 2004 Location: Eastern Pa Posts: 2,671	Ok, I got him tonight! The drinking glass trick worked!!! I took a tall glass and laid it against the rock enough of an angle that it could climb down in and when it did it would slide down to the bottom of the glass and thus not be able to get traction to get back out. At first he was leary, but then fell for it. He it GONE now.. I wrapped some seaweed around a small rock with a rubber band to coax him in.. Thank god this thing is out of there. His coral eating days are over. I actually caught him grab a hermit crab and start to eat the shell around the little hermit.. His claws were longer than his body when stretched in front of him. This is one mean looking dude!!! Outa here! Thanks Spankey __________________ 75RR. 6x54w T5. Vortech, Reef Octopus Recirc Skimmer, RKL Controller.. On a restocking Frenzy ;0

05/04/2006, 08:35 PM	#26
Markarian421 Premium Member Join Date: Dec 2003 Location: EastSFBay, CA Posts: 340	Which crab? The black one I have never touched any corals. The other one certainly did. Our black one is very shy, it never comes out in light and even in the dark stays at the back of rocks or close to them. We tried all kinds of traps with no luck. We finally caught him when we were rearranging part of our tank and had a bunch of bare rocks -- at midnight the other night I saw him on one of those rocks, and my wife pulled the rock out the the tank as I followed with a net, and it dropped off the rock into the net. If your crab is attacking corals though, no need to be nice unless you really want to. Go after it with an ice pick.

05/05/2006, 08:43 AM	#31
Markarian421 Premium Member Join Date: Dec 2003 Location: EastSFBay, CA Posts: 340	I used to feed ours by giving it a rolled up piece of nori with tongs. It would come out at feeding time anyway to get food, and became less and less shy. But once fish started to vanish, keeping it well fed with nori didn't seem to matter.

02/03/2007, 12:24 AM	#33
Newflavor Registered Member Join Date: May 2006 Location: Toronto Posts: 240	do you have a pic of thiscrab?

02/03/2007, 06:41 AM	#34
spankey Registered Member Join Date: Dec 2004 Location: Eastern Pa Posts: 2,671	No I deleted it some time ago. It was an emerald crab that when in adult stage they get huge and sometimes eventually turn black... If you look at emerald crabs thier claws look scoop like at the tips.. Thats what this was __________________ 75RR. 6x54w T5. Vortech, Reef Octopus Recirc Skimmer, RKL Controller.. On a restocking Frenzy ;0

06/15/2007, 11:43 PM	#35
vangoghfish Registered Member Join Date: Jan 2007 Location: Atlantic City Posts: 541	I have one like Dr4g0nf1y's photo of crab in hand, what kind is it, got one as a hitchhiker on a nice piece of live rock I just recently got, preditor, or ok, mine is about 2-1/2", nice size.

06/16/2007, 05:02 AM	#36
Markarian421 Premium Member Join Date: Dec 2003 Location: EastSFBay, CA Posts: 340	It's some kind of mithrax. Mine was ok for a long time, a great algae eater, but it eventually started to pick off chromis.

12/18/2007, 08:04 PM	#37
4218kris Registered Member Join Date: Nov 2007 Location: mesa Posts: 1,414	crab id does anyone know what kind of crab this is? [IMG] http://reefcentral.com/gallery/data/...97100_1161.jpg[/IMG]

12/18/2007, 11:30 PM	#38
Dr4g0nf1y Premium Member Join Date: Dec 2004 Location: Shavertown, PA Posts: 692	Start here http://reefkeeping.com/issues/2003-12/rs/index.php Pay attention to the portion of the article that deals with body shape to identify species.

05/30/2008, 11:58 AM	#39
steel3470 Registered Member Join Date: Mar 2006 Location: akron ny 14001 Posts: 431	im always looking to get those types of crabs for my crab only tank.

03/28/2012, 08:56 PM	#40
Ahall003 Registered Member Join Date: Mar 2012 Posts: 1	Need an ID Can anyone help ID this guy, I found him on st Augustine beach fl, thanks! http://www.facebook.com/photo.php?fb...5&l=e41817289b

03/29/2012, 07:50 PM	#41
bunzaroo Registered Member Join Date: May 2008 Location: Miami,FL Posts: 617	Looks like a ghost crab __________________ Current Tank: Mized Reef 72 Bowfront, 105G (45X27X20) Reef Savvy Rimless in the works. Current Tank Info: 105 Gallon Reef Savvy Rimless, Mostly LPS/NPS and anemone's, 3 Bartlett Anthias, Royal Gramma, Green Spotted Mandarin, Yellow Tang, 2 Banghai Cardinals.

03/29/2012, 08:29 PM	#42
anaya Shh Lets Not talk Cost! Join Date: May 2010 Location: North East Tennessee Posts: 315	I have two in my tank and I love em! Well mine look identical to them except they are an awesome purple color. I get mine to come out by feeding the rest of my tank first, then I locate them with a flashlight if necessary. After finding them I simply get there attention with a chunk of fish flesh. I usually tease them enough to get them to come out of there hide spot and onto the sand-bed. I would think you could do the same but have a small piece of plexiglass and a net at the ready. Once it is on sand bed keep it distracted with the food, slip the plexi between it and the rocks, blocking his escape route, using the net to scoop it up. Best of luck, try to not kill it if your LFS will take it back. People like me would love to have the little monster. Antonio __________________ Please take heed that what I share is my opinion or an experience I've had. It's not advise or any type of suggestion as for what will work for you or what will not. It's simply a point of view to put ideas in place that should be researched further so you can come to your own educated decision. Current Tank Info: 29gal macro/grow tank. 75gal eel (G. fimbriatus). 40breeder eel (future home for E. carychoa), 40 breeder eel (future home for 2 GDM's). 75gal eel (undecided). 10gal feeder holding tank.