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My LFS has acquired some shrimps. However, he doesn't know what they are (the wholesaler was apparently completely ignorant of their identity and thus couldn't provide anything other than "They're freshwater shrimps" by way of information), and they're posing a bit of a mystery to me too.

In appearance, they look at first sight as if they ought to be a Macrobranchium long-arm shrimp. Indeed, they bear some resemblance to the creature labelled as "Indian Shrimp" on this page. However, there are some key differences.

Sadly I don't have a photo of this beast, but I can provide a fairly comprehensive description, and I have found an illustration that gives some idea of what I've seen, but as stated above, there are differences. If you look at the illustration from the page above, which for ease of reference I shall link to here, the description can be given in terms of similarities and differences as follows:

Similarities:

[1] Body morphology, particularly the manner in which the abdomen is noticeably 'humped', and the pointed rostrum protruding in front of the eyes.

[2] Colouration. The basic colouration of the shrimp (at least that of the body) matches that of the illustration of the "Indian Shrimp" on that site.

Differences:

[1] Claw bearing 'arms'. The 'arms' bearing the claws on the mystery shrimp are more sturdily constructed than those seen in the photo of the shrimp on the website. Instead of being twig like, they are fairly robust, and have noticeable joint articulations even thogh the shrimp itself is only 2 cm long. Furthermore, the 'arms' of the mystery shrimp bear a distinctive and easily seen 9to the naked eye) striped pattern, in which each arm bears 5 or 6 vertical dark brown stripes. In fact, the arms of this freshwater shrimp bear a considerable resemblance to those of the well known marine Stenopus hispidus or Boxing Shrimp.

Aside from identification, I'd also like some hints and tips on keeping Macrobranchium shrimps. How compatible are they with fishes? I've seen some pages that state problems - small specimens are harassed, and larger species can turn the tables upon smaller aquarium fishes (indeed this page says that one species, Macrobranchium rosenbergii, grows large enough to be predatory on Zebra Danios, and is quick enough to catch and eat them!).

The shrimp in question is an intriguing critter. Trouble is, if it's likely to be problematic alongside my fishes, or prove to be troublesome to maintain even in a species aquarium because of dietary needs, I'm obviously best leaving this alone.

Anyone care to assist?


Panda Catfish fan and keeper/breeder since Christmas 2002

Im not sure about the specific species,but the description you give sounds like the shrimp could be trouble.During the day it might well be fine, but its at night with sleepy fish that the shrimp often do the damage.Shrimp arent usually "tooled up" for no reason. This one could be a night killer, id approach the purchase of them with caution. I have a feeling this shrimp isnt thusly armed for just display or courship and fighting with conspecifics.

Check out petshrimp.com. It's dedicated to shrimp only and you should get an ID.

Already tried there Baz, and they don't have it listed ...

Oh, and LHG, I've already seen warnings about Macrobranchium shrimps elsewhere - one of the pages I linked to above says that one of the bigger species will even catch Zebra Danios and eat them if it's hungry, apparently some of these shrimps have lighning reflexes!

That's the trouble with quite a few shrimps - they're appealing to look at, but fish compatibility is a headache. Either they're likely to end up as lunch for the fish, or some of them will snack upon small fishes themselves. Sigh.

Even though this one is only 2 cm long at the moment, and doesn't look as if it can do much damage, there's no telling how big it'll grow. If it ends up around 6 or 7 cm, then there's no way I'd put it in the Panda Fun Palace because it might nip the Pandas and eat one or two of the Cardinals ... I'm just hoping that this critter is NOT Macrobranchium rosenbergii because that's got quite a reputation ...


Panda Catfish fan and keeper/breeder since Christmas 2002

That's why I like to stick with Neocaridina species. One interesting interaction I've seen is one of my albino cories likes to let my cherry shrimp "groom" it. The first time I saw this I thought that the albino was dead as it was laying on it's side with a shrimp picking at it. As soon as I tapped on the glass the cory righted itself and resumed looking for food in gravel. It has happened a few times since.

You'll probably find more information if you search under the correct genus heading - Macrobrachium.

If you provide an image, I might be able to give a more exact ID. Many of the South/Southeast Asian "ghost shrimp-type" Macrobrachium are basically harmless to fish.

Aside from identification, I'd also like some hints and tips on keeping Macrobranchium shrimps. How compatible are they with fishes?

Macrobrachium lanchesteri, often misidentified as "Macrobrachium lar" in continental Europe, is among the most community-suited members of the genus. This species is, in the U.K., frequently marketed (along with native brackish-water Palaemon spp.) as a feeder "ghost shrimp".

I've seen some pages that state problems - small specimens are harassed, and larger species can turn the tables upon smaller aquarium fishes (indeed this page says that one species, Macrobranchium rosenbergii, grows large enough to be predatory on Zebra Danios, and is quick enough to catch and eat them!).

Macrobrachium rosenbergii, to be precise, grows so large that zebra danios would not be worth the effort of pursuit. Look to the following images:

"Kentucky King"

Exuvia

Gallery

Given what I've seen, Macrobum shrimp will make meals out of fish, so fish would be asking for trouble...

Just took a look at that rosenbergii.

That is food for a family of four, that whopper!

I'm going to see if I can obtain a photo of the critter. Can't guarantee I'll be able to, but here's hoping that it's still there when I pay my next visit to the LFS.


Panda Catfish fan and keeper/breeder since Christmas 2002