I found them in a local pond in Antigua that does not connect to the sea as far as I know. I think it's some kind of macrobrachium but I have no idea which one. I'd really like to find out more about them and if they keep well in tanks. Thanks
Can someone ID this prawn for me please?
- Thread starter Ms Caribbean
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These are Macrobrachium carcinus. I've kept them before -- they make very engaging aquarium inhabitants, so long as you have a large enough tank (and they do get fairly enormous) furnished with hiding and climbing spots. It's probably best if you maintain them singly to preclude cannibalism during molts. Much more "personality" than any other invertebrate I've kept ... comparable to a large cichlid in many respects.
The fact that you found them in a pond unconnected to the ocean is interesting, as the larvae of pretty much all Caribbean Macrobrachium are thought to be uniformly unable to mature in freshwater. Is it possible that there might be temporary spillover into streams during high rainfall?
The fact that you found them in a pond unconnected to the ocean is interesting, as the larvae of pretty much all Caribbean Macrobrachium are thought to be uniformly unable to mature in freshwater. Is it possible that there might be temporary spillover into streams during high rainfall?
Thanks for the ID. I'm not sure about the temporary spillover since this is a pretty dry place and high rainfall is rare. I guess anything is possible. I also saw some juveniles in the pond and any heavy rainfall that would connect the pond to any other water ways hasn't happened in quite a while. I guess all I can do is wait and see.
How stressed were the shrimp when you took the photo (they obviously are out of water)? Have they darkened since you took that picture? The M. carcinus that I've seen had much more contrast in color, than those in your picture. If their color remains mute, they could be another species.
FYI, the quick and dirty way of determining if a Macro species requires brackish/saltwater to mature, is by egg size. If the eggs are very tiny, they'll most likely need an estuarine environment to mature. The common theory is; smaller eggs produce larvae that mature through several (7-9) larval stages. Comparatively larger eggs do not. The same rule can be applied to any crustacean (dwarf shrimp, crawdads, crabs).
FYI, the quick and dirty way of determining if a Macro species requires brackish/saltwater to mature, is by egg size. If the eggs are very tiny, they'll most likely need an estuarine environment to mature. The common theory is; smaller eggs produce larvae that mature through several (7-9) larval stages. Comparatively larger eggs do not. The same rule can be applied to any crustacean (dwarf shrimp, crawdads, crabs).
Stress can affect coloration, yes, but the claw shape and body form guarantee that they're M. carcinus (and not M. acanthurus, M. crenulatum, M. faustinum, M. heterochirus or an introduced species like M. rosenbergii -- the other species which could conceivably occur in Antigua). The dominant color of carcinus can range from off-white or pale olive to quite dark brown or an almost metallic blue ... in some places, you'll also see animals exhibiting yellow stripes along the sides.
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If these are Carcinus (which i assume they are judging by claws) they are probably one of the largest and nastiest of the Macrobrachium species. Their claws are no joke.
Been trying to find one of these for my tanks. All Macros aside from the small red claw kind are hard to find these days.
Been trying to find one of these for my tanks. All Macros aside from the small red claw kind are hard to find these days.