ID?

[ToddnBecka]

Anyone know what species this one is?

[badflash]

Looks to be a young orange claw macro to me. M. Rosenbergii.

[ToddnBecka]

Thanks, someone on another forum had it posted as a ghost shrimp. I passed the word along.

[badflash]

Not ghost shrimp. The fellow on the pot will likely get to be 8"-10" in 6 months or so given food & room. He'll also make lunch of most of the tank mates, including his own kind. This includes females.

[ToddnBecka]

Will it eat fish as well? I would never have thought a FW shrimp would grow so large, and be so aggressive. I've heard about the SW mantis shrimp, both the harpooner and the hammer. The hammer type have been known to break aquarium glass, yet a few folks still want one for their tanks.

[Veneer]

Will it eat fish as well? I would never have thought a FW shrimp would grow so large, and be so aggressive.

To put it simply, M. rosenbergii will eat fish (though small, swift-moving species are sometimes ignored). Some aquarists have claimed success with adult prawns and certain comparably-sized predatory fish, but such setups should never be held to have true long-term viability.

As this image should attest, a length even of 10" is unexceptional for fully-grown M. rosenbergii.

I've heard about the SW mantis shrimp, both the harpooner and the hammer. The hammer type have been known to break aquarium glass, yet a few folks still want one for their tanks. :roll:

For many, the appeal of mantis shrimp (Stomatopods, and thus not actual shrimp) lies not only in their predatory prowess but also in their intelligence and stunning coloration.

[ToddnBecka]

Ouch, that monster could take on an oscar

[badflash]

I find that mine are not big fish eaters, but that is atypical. Mine were raised from 1/8" post-larvals to their current 6" size with a large population of apple snails and endlers. They are well fed and have not really ever learned to hunt. Wild caught are an entirely different critter and will litterally clean out a tank just for sport. Those long arms are not just for show. A 10" shrimp can reach 10" for a fish in any direction. Put him in the middle of a 20 gallon tank and just abou anything is in range.

[Mustafa]

Ouch, that monster could take on an oscar

An oscar of about the same body size (or even a little bit smaller) would kill and eat (well...at least begin to eat..as it's huge) such a shrimp in short order. Crustaceans are no match for predatory cichlids...I've seen it with my own eyes years ago. Predatory cichlids instictively bite off claws and legs first, so the shrimp is incapacitated...then they bite it to death...not a pretty sight.

[The Fisherman]

Ouch, that monster could take on an oscar

An oscar of about the same body size (or even a little bit smaller) would kill and eat (well...at least begin to eat..as it's huge) such a shrimp in short order. Crustaceans are no match for predatory cichlids...I've seen it with my own eyes years ago. Predatory cichlids instictively bite off claws and legs first, so the shrimp is incapacitated...then they bite it to death...not a pretty sight.

I will agree with that....I've seen the same thing when a Puffer attacks a crusteacean. Not pretty....

-John (AKA: The Puffer Ninja)

[ToddnBecka]

Are these critters ever sold as such, or just turn up accidentally among ghost shrimp shipments? I've seen a few posts on other forums, folks buying ghost shrimp, and having one or more Macro's among them. I've never seen any myself, but wouldn't know what to look for to spot the difference. They look like an interesting species, how difficult are they to keep/breed?

[badflash]

Yes, they are, but rarely available. Most of the time they end up being dumped as "ghost shrimp" by suppliers that can't move them. They are difficult to ship once they get bigger than about 1.5" as they rip holes in fish bags. I've had to resort to using tuperware containers to ship them. This also pushes up the shipping weight to about 1.5# per animal so shipping express is expensive. There is not a lot of interest in these guys as they take so much space and eat their tank mates. I had thought there would be more hobby interest, but there just doesn't seem to be.