What Type Of Shrimp Is This?

[Aquarian58]

I have two shrimps, which I acquired almost a month ago, in my 90 litre tank and they seem to be thriving, although I have no prior experience in keeping them and I'm not feeding them anything other than the food their tank mates get (a mixture of various types of store-bought flakes and freeze dried blood worms).
 
I posted a couple of pics in another topic, curious to know what species they are but I don't want to derail that thread with my questions so I thought I'd take up the question here.

 
They came out of a tank of feeder fish and were virtually transparent at the time but now they are in my tank their colour varies from shades of speckled tan to almost chocolate.
 
Most of the time they seem to blend in with the substrate, but lose their colour when they swim to the surface to in search of food.
 

 
I've become quite fond of these little guys and I'm hoping they continue to do well in my tank, virtually maintenance-free and if someone could identify them from these rather grainy pics it would be a bonus

 

[BettaBettas]

Japanese shrimp

 

[Aquarian58]

I googled "Japanese shrimp" and only found pictures of shrimp battered and deep fried

 
Do you have a scientific name for them BettaBettas?


 
A couple more pics
 
Note two sets of pincers

 

[BettaBettas]

google, "Aquarium Japanese Shrimp"

their the ones with the stripe through the center of their body

 

[Baccus]

You should never try to identify shrimp purely by their markings this can and will lead you down all sorts of garden paths. Instead look at the rostrum and legs and nippers. Going by the nippers on your shrimp even with the pictures not very clear I would suggest that they are a species of Macrobachium. Depending on what type of macrobachium that they are then it will determine just how large they will get.
Since your in Australia I would say yours could be long armed shrimp, which is a Macrobachium species.
It would help a lot in identification if you knew if the shrimp where wild caught locally (eg the person who sold the tank caught the shrimp in a local waterway) or if they where purchased from a shop because some different macrobachium species are sold in various shops.
Being macrobachium I would watch them closely with any fish, they can be effective hunters, they will also happily eat snails.
 
Also of note in Australia we do not have Amano shrimp, the closest we have are Typhus shrimp which yours are not since typhus do not have long nippers. Riffle shrimp another native do not even have nippers instead they filter feed with baskets.

 

[Aquarian58]

Thanks Baccus.
 
They came from a specialist aquarium store which I happened to visit but is not in my local area.
 
Various websites I've been looking at seem to confirm your suggestion in the other topic that they are Macrobrachium, although I haven't yet found a pic that accurately represents the two shrimp I have.
 
There seems to be a lot of variety within that species, but they definitely have two sets of pincers, one long set and one short, close to their mouths for holding and nibbling food particles.
 
I could call the aquarium and ask, I guess, but based on the conversations we had while I was there, I'm not confident the staff would even know.
 
And if they enjoy a meal of MTS, all the better

 

[Baccus]

Long Armed Shrimp are the most commonly sold macrobachium species sold in Australia however there are a couple of other species sold at times too. I suspect because so little actual identifiction work has been done on our Australian species of shrimp that many macros of different sub or similar species are simply sold as macrobachium.
 
Here are another couple of Macros that are available in the fish trade
http/www.aquagreen.com.au/plant_data/Macrobrachium_bullatum.html
 
http/www.aquagreen.com.au/plant_data/Macrobrachium_handschini.html
 
I don't know if they would be hugely effective at snacking on MTS but ramshorns would be an easy target for them, because Ramshorns do not have a trapdoor they can lock when threatened.

 

[Aquarian58]

Thanks again Baccus.
 
Whatever they are they give me a lot of enjoyment at the moment with their cheeky behaviour and that especially applies to the larger one which is increasingly interactive, especially at meal times.
 
And point of order, all the references to Macrobrachium that I've come across have two "r's" not one

 

[Baccus]

 That's probably from me trying to type to fast

 .
 
Macros certainly can be entertaining they get to know you and food times quite well. If you do have two males just watch out for aggression between them especially as they mature, some people have reported them being a bit like yabbies and ripping each others nippers off.
 
This is a small local macrobrachium that I caught in my area

 

 

 
If you really want to give your shrimp a treat that they will love give them some defrosted bloodworms.

 

[Aquarian58]

Yes, there are a lot of similarities between your shrimp and mine.
 
I guess the difference in colouration and patterns is a regional thing and it's perhaps an adaptive thing like squid where they are able to camouflage themselves to some extent for protection, especially when there's a tank full of hungry fish swimming above and around them 24/7/
 
I have plenty of cover for them but they seem content to mingle with with their co-inhabitants most of the time.
 
Thanks for the pics too, Baccus...your shrimp look to be right at home in their surroundings

 

[Baccus]

Colouration can be a regional thing but also habitat. Those photos where taken of the macros not long after I caught them in a creek, hence why I said never try to identify a shrimp just by its markings. When shrimp get stressed one of the first things they usually do is drop their colour, I find this especailly with local "glass" shrimp. When first caught  "glass" shrimp (most likely Paratya australiensis) can be a range of colours and have a mix of markings but given a few minutes "stressed they can drop the colours and not recover them in a tank situation.

 

[Ch4rlie]

I have to concur with Baccus on this, this does indeed look like machrobrachium. And yes, they do change colourations depending on their stress and environments.
 
As she says, they are truly interesting in their own right but I'd honestly never put these 'shrimps' into a community set up at all.
 
Certain species of these grow as large as lobsters

 

[Aquarian58]

Points noted Ch4rlie

 
As for growing "as large as lobsters" I assume if that were to happen it would transpire over many months and not overnight

 
They are very easy to monitor because they are regularly out looking for food and their hiding spots will only conceal them as long as they remain under 75mm or 3 inches in length.
 
Beyond that, they'll need their own tank and I have plenty of time to plan for that, even if they have a growth spurt

 

[Aquarian58]

I'm yet to definitively identify the species of my two shrimp but one thing I do know is that they love newborn Guppy fry as a meal.
 
This one was born about 30 seconds prior to me taking the pic and 30 seconds later one of the shrimp came out from underneath the leaf the fry is resting on and grabbed it and disappeared under the leaf again
 

 
The mother Guppy gave birth to several fry over a 10 minute period and I'm thinking there's a very good chance they ended up as shrimp fodder, like this little fella

 

[Baccus]

A macro snacking on a fish fry really does not surprise me I have witnessed them snatching tetras, guppys and flyspecked hardy heads as the fish innocently swim past.