Horseshoe Crab

thecichlidpleco · 04/06/2007, 11:14 AM

My LFS sells horseshoe crabs, and I was wondering if they serve any purpose or if they are only in the store for impulse buyers, like buying mandarins or panther groupers. Seeing how big they get on some nature channels, can someone even house one?

marduc · 04/06/2007, 11:17 AM

impulse buy.. they will get huge. I think they eat detritus.. but they will get big quick and be bulldozers, no good unless you have a 1000 gallon or so tank.

Blown 346 · 04/06/2007, 11:22 AM

Like said above, you also need a very deep sand bed for them.

thecichlidpleco · 04/06/2007, 11:24 AM

Damn money grubbing LFS, you think anyone would even point out how big they get?

useskaforevil · 04/06/2007, 11:28 AM

im pretty sure there is a kind that does not grow huge, at least soemone (who wasnt selling them) claimed there was.

cham · 04/06/2007, 12:00 PM

I put some in my 110 over a year ago and they were no bigger than a quarter. From what I can tell they have grown very little. A few millimeters at most.

Have a 3" sand bed.

Most did die though, only a couple left of the 4 or 5 I put in.

Questin · 04/06/2007, 12:16 PM

Yes, there is a small species of these that you can put in a tank.

kraftyforu · 04/06/2007, 12:28 PM

i have a very small one in my tank and has been in there for about 4 months now. does a good job keeping the top layer of sand clean

jimwat · 04/06/2007, 12:38 PM

The only Horseshoe listed on Live Aquaria says it can grow to 2 feet.

plummike · 04/06/2007, 12:47 PM

There is a small breed. A store in Pgh sells them says they get about 1" across

Samala · 04/06/2007, 01:15 PM

Absolutely unfounded, there are no dwarf species or variants of American horseshoe crab. The true species is Limulus polyphemus, and while there is some distinction in size between males and females, and across their range on the eastern coast of the US (larger in the North than in the Southern waters), they all reach at least 7" across.

Most will get quite a bit larger, 12-14" not being uncommon among the females. If you include the telson, the 2ft measurement is certainly likely.

The only remaining species of horseshoe crab outside of North America occur in Pacific Waters near Japan and the Philippines. They have distribution across other, more Southern waters as well and in the Indian Ocean. This includes the Tachypleus genus and the lone member of the Carcinoscorpius genus. Each of these also get to a considerable size.

I have never encountered horseshoe crabs other than Limulus polyphemus in American LFS. It is very possible to starve these creatures to death, resulting in extremely slow growth rates. They may stay at that quarter to 1" size for many months, delaying further development, but they will not survive this sort of treatment.

In the wild these animals consume plankton when young, benthic copepods, they will eat some measure of detritus but they focus on benthic shellfish and worms. It is possible to raise Limulus on baby brine shrimp, mysis and graduate them on to oyster and squid strips, substituting in frozen capelin and pollock. In my experience thriving Limulus will add about 1-1.5" to their shell size each year of their life.

>Sarah

Lpabsolute · 04/06/2007, 01:47 PM

I use to have 3 in my 1st Salt Water Tank. They did fine, but always hid in the sand. They are fine and cheep around here. No more different than owning a brittle starfish IMO.

SCR · 04/06/2007, 02:53 PM

They don't seem to grow very fast, but don't seem to live very long either. At lease not in my tanks.

Jadams · 04/06/2007, 03:11 PM

I have one in my tank which is very small...he does a great job of mixing the sand bed (mine being close to 4") and keeping the top layer clean for friends when they come over to check out the tank. they will get large, but not for a very long time

Samala · 04/06/2007, 03:30 PM

You can check out horseshoecrab.org for more information if you're interested, it gives a great amount of information about their evolution and life history.

Generally American HSC take ten years to mature to adult size, so they are certainly slow growers. But then can live well into their twenties. We suspect a few may even reach their thirties before they die.

>Sarah

useskaforevil · 04/06/2007, 05:18 PM

"It is very possible to starve these creatures to death, resulting in extremely slow growth rates."

haha you don't say?

useskaforevil · 04/06/2007, 05:42 PM

also, we never said american horseshoe crab. Carcinoscorpius rotundicauda apparently only gets to be about 5inches in diameter which i would consider small.

Samala · 04/06/2007, 07:26 PM

Show me a photo of Carcinoscorpius available in an American LFS then. I have seen many examples of horseshoe crabs in our shops, and they are all Limulus, for various reasons. The most important one probably being the easy access to them from our own coasts.

All of the Limulidae are on the IUCN Red List. Carcinoscorpius and the two Tachypleus are listed data deficient (much like the entire Hippocampus genus) pending further research. Limulus is actually listed under Lower Risk/near threatened for the time being. There are consistently moratoriums on their catch within their most populated areas along the eastern coast. I would be surprised to see Carcinoscorpius or Tachypleus here in the States, unless they are dried chitin shells in the curio trade.

Regardless, none of them stay at the 1" mark proposed, and there are no dwarf species or breeds.

>Sarah

KzooGirl · 04/06/2007, 07:33 PM

I have personally had one of these. If you have live sand it won't be live for long. I think that they're very interesting but I wouldn't buy another one unless I had a huge tank with tons of live sand. I think that they're probably better off in the ocean where they can find plenty of suitable food and be able to grow to their full potential.

sabien · 01/02/2010, 03:08 AM

Everything we keep in our tanks is better off in the ocean.

I laugh when I see people post this. If you learn to feed them properly they will do just fine and thrive. I feed mine daily simply by flipping them upside down and feeding small pieces of shrimp.

I have two of them in a 240 gal with 6" sandbed. I still have plenty of bristle worms and other inverts thriving and I've had mine for two+ years. They are wonderful at keeping the sand clean.

They die when you don't properly care for them. They're actually pretty easy.

04/06/2007, 11:14 AM	#1
thecichlidpleco Registered Member Join Date: Dec 2006 Location: Ann Arbor Posts: 1,227	Horseshoe Crab My LFS sells horseshoe crabs, and I was wondering if they serve any purpose or if they are only in the store for impulse buyers, like buying mandarins or panther groupers. Seeing how big they get on some nature channels, can someone even house one? __________________ knowledge is power, power leads to abuse, study hard, be evil Owning a tank is like being with that girlfriend who could care less about you, but you couldn't stand being without her. Current Tank Info: 125 Reef, (3) 250w aquamedic oceanlights ETSS 600 skimmer, mag12 return, (2) Tunze 6055's with 7095 controller, 100 gallon sump

04/06/2007, 11:24 AM	#4
thecichlidpleco Registered Member Join Date: Dec 2006 Location: Ann Arbor Posts: 1,227	Damn money grubbing LFS, you think anyone would even point out how big they get? __________________ knowledge is power, power leads to abuse, study hard, be evil Owning a tank is like being with that girlfriend who could care less about you, but you couldn't stand being without her. Current Tank Info: 125 Reef, (3) 250w aquamedic oceanlights ETSS 600 skimmer, mag12 return, (2) Tunze 6055's with 7095 controller, 100 gallon sump

04/06/2007, 11:28 AM	#5
useskaforevil Registered Member Join Date: Jan 2007 Location: kent, ohio Posts: 1,012	im pretty sure there is a kind that does not grow huge, at least soemone (who wasnt selling them) claimed there was. __________________ "and the delicate mechanism stripped its gears" Current Tank Info: 80gallon bowfront

04/06/2007, 12:38 PM	#9
jimwat Premium Member Join Date: Apr 2003 Location: South Florida Posts: 1,270	The only Horseshoe listed on Live Aquaria says it can grow to 2 feet. __________________ "Give a man a fish and he will eat for a day. Teach a man to fish and he will sit in a boat all day and drink beer." Current Tank Info: 65 gal with 192w PC 10k, 192w VHO actinic, Blue-Moon LED, Tunze 6060 on WavySea, AquaController 3. 20gal sump, Natureef CDECX-1, Phosban Reactor, Remora, Kalk Drip, Ozone.

04/06/2007, 01:15 PM	#11
Samala Registered Member Join Date: Jun 2003 Location: Orlando, FL Posts: 2,930	Absolutely unfounded, there are no dwarf species or variants of American horseshoe crab. The true species is Limulus polyphemus, and while there is some distinction in size between males and females, and across their range on the eastern coast of the US (larger in the North than in the Southern waters), they all reach at least 7" across. Most will get quite a bit larger, 12-14" not being uncommon among the females. If you include the telson, the 2ft measurement is certainly likely. The only remaining species of horseshoe crab outside of North America occur in Pacific Waters near Japan and the Philippines. They have distribution across other, more Southern waters as well and in the Indian Ocean. This includes the Tachypleus genus and the lone member of the Carcinoscorpius genus. Each of these also get to a considerable size. I have never encountered horseshoe crabs other than Limulus polyphemus in American LFS. It is very possible to starve these creatures to death, resulting in extremely slow growth rates. They may stay at that quarter to 1" size for many months, delaying further development, but they will not survive this sort of treatment. In the wild these animals consume plankton when young, benthic copepods, they will eat some measure of detritus but they focus on benthic shellfish and worms. It is possible to raise Limulus on baby brine shrimp, mysis and graduate them on to oyster and squid strips, substituting in frozen capelin and pollock. In my experience thriving Limulus will add about 1-1.5" to their shell size each year of their life. >Sarah __________________ "Seaweed is cool, seaweed is fun, it makes its food from the rays of the sun!"

04/06/2007, 11:17 AM	#2
marduc Registered Member Join Date: May 2003 Location: Tampa, Fl. Posts: 780	impulse buy.. they will get huge. I think they eat detritus.. but they will get big quick and be bulldozers, no good unless you have a 1000 gallon or so tank.

04/06/2007, 11:22 AM	#3
Blown 346 Registered Member Join Date: Apr 2004 Location: Rockford, Illinois Posts: 6,596	Like said above, you also need a very deep sand bed for them.

04/06/2007, 12:00 PM	#6
cham Registered Member Join Date: Jun 2006 Location: Winter Garden, FL Posts: 3,632	I put some in my 110 over a year ago and they were no bigger than a quarter. From what I can tell they have grown very little. A few millimeters at most. Have a 3" sand bed. Most did die though, only a couple left of the 4 or 5 I put in.

04/06/2007, 12:16 PM	#7
Questin Registered Member Join Date: May 2003 Location: Colorado Springs Posts: 784	Yes, there is a small species of these that you can put in a tank.

04/06/2007, 12:28 PM	#8
kraftyforu Registered Member Join Date: Feb 2005 Location: Wetumpka, alabama Posts: 637	i have a very small one in my tank and has been in there for about 4 months now. does a good job keeping the top layer of sand clean

04/06/2007, 12:47 PM	#10
plummike Registered Member Join Date: Jan 2006 Location: near Pittsburgh Posts: 271	There is a small breed. A store in Pgh sells them says they get about 1" across

04/06/2007, 01:47 PM	#12
Lpabsolute Registered Member Join Date: Sep 2004 Location: Johns Island, SC Posts: 2,021	I use to have 3 in my 1st Salt Water Tank. They did fine, but always hid in the sand. They are fine and cheep around here. No more different than owning a brittle starfish IMO. __________________ "Do not float above me when I'm drowning in the abyss......float away from me.........float away" Current Tank Info: 54g Corner Reef Tank......and......5.5g Nano Reef Tank......and......20g Long Reef Tank.......and......27g Cube

04/06/2007, 02:53 PM	#13
SCR Registered Member Join Date: Feb 2005 Location: Central, Fl Posts: 708	They don't seem to grow very fast, but don't seem to live very long either. At lease not in my tanks.

04/06/2007, 03:11 PM	#14
Jadams Registered Member Join Date: Dec 2005 Posts: 4,475	I have one in my tank which is very small...he does a great job of mixing the sand bed (mine being close to 4") and keeping the top layer clean for friends when they come over to check out the tank. they will get large, but not for a very long time __________________ Jeremy

04/06/2007, 03:30 PM	#15
Samala Registered Member Join Date: Jun 2003 Location: Orlando, FL Posts: 2,930	You can check out horseshoecrab.org for more information if you're interested, it gives a great amount of information about their evolution and life history. Generally American HSC take ten years to mature to adult size, so they are certainly slow growers. But then can live well into their twenties. We suspect a few may even reach their thirties before they die. >Sarah __________________ "Seaweed is cool, seaweed is fun, it makes its food from the rays of the sun!"

04/06/2007, 05:18 PM	#16
useskaforevil Registered Member Join Date: Jan 2007 Location: kent, ohio Posts: 1,012	"It is very possible to starve these creatures to death, resulting in extremely slow growth rates." haha you don't say? __________________ "and the delicate mechanism stripped its gears" Current Tank Info: 80gallon bowfront

04/06/2007, 05:42 PM	#17
useskaforevil Registered Member Join Date: Jan 2007 Location: kent, ohio Posts: 1,012	also, we never said american horseshoe crab. Carcinoscorpius rotundicauda apparently only gets to be about 5inches in diameter which i would consider small. __________________ "and the delicate mechanism stripped its gears" Current Tank Info: 80gallon bowfront

04/06/2007, 07:26 PM	#18
Samala Registered Member Join Date: Jun 2003 Location: Orlando, FL Posts: 2,930	Show me a photo of Carcinoscorpius available in an American LFS then. I have seen many examples of horseshoe crabs in our shops, and they are all Limulus, for various reasons. The most important one probably being the easy access to them from our own coasts. All of the Limulidae are on the IUCN Red List. Carcinoscorpius and the two Tachypleus are listed data deficient (much like the entire Hippocampus genus) pending further research. Limulus is actually listed under Lower Risk/near threatened for the time being. There are consistently moratoriums on their catch within their most populated areas along the eastern coast. I would be surprised to see Carcinoscorpius or Tachypleus here in the States, unless they are dried chitin shells in the curio trade. Regardless, none of them stay at the 1" mark proposed, and there are no dwarf species or breeds. >Sarah __________________ "Seaweed is cool, seaweed is fun, it makes its food from the rays of the sun!"

04/06/2007, 07:33 PM	#19
KzooGirl Registered Member Join Date: Apr 2007 Location: Michigan Posts: 4	I have personally had one of these. If you have live sand it won't be live for long. I think that they're very interesting but I wouldn't buy another one unless I had a huge tank with tons of live sand. I think that they're probably better off in the ocean where they can find plenty of suitable food and be able to grow to their full potential.

01/02/2010, 03:08 AM	#20
sabien Registered Member Join Date: Jan 2006 Location: Suwanee, GA Posts: 71	Everything we keep in our tanks is better off in the ocean. I laugh when I see people post this. If you learn to feed them properly they will do just fine and thrive. I feed mine daily simply by flipping them upside down and feeding small pieces of shrimp. I have two of them in a 240 gal with 6" sandbed. I still have plenty of bristle worms and other inverts thriving and I've had mine for two+ years. They are wonderful at keeping the sand clean. They die when you don't properly care for them. They're actually pretty easy.