Any idea what these are?

[yabadaba]

Hi guys, I picked up two shrimp from my lfs a couple of weeks ago and they are doing just fine, but the guy in the shop wasn't sure what variety they were. I would imagine they are quite a common species, based on what he normally stocks, but I haven't been able to find any that look the same when 'googling' around. Can any of you experts here kindly help me identify them?

Sorry, forgot to mention their size, as you might not be able to gauge that from the pictures - ones about 3" long and the other about 3.5" long, which is body-only and excluding their legs/claws.

[Mustafa]

Hmm....do you have a clear picture where their claws are visible? It's obviously a Macrobrachium sp. , just don't know which one.

[yabadaba]

Thanks Mustafa. Here's a couple of pictures of the smaller of the two that hopefully show the claws better/differently. The larger shrimp that appeared in the first pictures has slightly thicker, stronger looking claws, but otherwise they look the same.

[Mustafa]

Sorry, but this is one of those cases where I just don't know. It's definitely not a "common" shrimp in the hobby. You get "by-catches" and occasional imports in stores once in a while and this is most likely such a case.

[auptimus]

They are amazing.
are they peaceful or aggressive in your tank?