Macrobrachium sp. with eggs and shrimplets - help on ID

bochr · Post by **bochr** » Tue Oct 11, 2005 12:40 pm

Hi there shrimplovers

I need some help to ID these new shrimps.
I bought 5 of them a week ago.
They were sold as "Algae Shrimp". But I'm pretty sure that they are not.
My own bet is that they are Macrobrachium lanchesteri.
The fish store kept them in a tank with nothing but gravel.
Some of them is missing claws, antennas and rostrum.
But they are eating well, and is allready looking better.
They are a bit aggressive towards each oter, but not as much as my M. cf. assamense.
3 of them was carrying eggs, when i bought them, and the first female released freesvimming larvae the same day, they were put in the tank.
The next day most of the larvae was gone, and after two days all larvae were gone. Until two days ago, when i found several 3-4 mm. long shrimplets crawling around in the tank.

Anyone with suggestions on a species?

Post by **Mustafa** » Tue Oct 11, 2005 11:05 pm

It's Macrobrachium lanchesteri, commonly sold as "Glass" or "Ghost" shrimp in Asian countries and Europe. The larvae develop in freshwater, that's why you found the benthic postlarvae.

bochr · Post by **bochr** » Wed Oct 12, 2005 8:05 am

Thanks for the ID.

I got a bit confused about the species, because the info on wirbellose.de says that the larvae should be freeswimming at least 4 weeks.
And mine were only swimming for 1-2 days.

Post by **Mustafa** » Wed Oct 12, 2005 9:30 am

You're welcome. 4 weeks sounds a bit too long to me, but 1-2 days sounds also unlikely. Even the American Freshwater Glass Shrimp (Palaemonetes paludosus), which has much larger eggs has larvae that are need about 7 days to become benthic postlarvae. Keep in mind that the quality of information on Wirbellose.de depends on who actually contributed that information. There is a lot of plain wrong information there still that needs to be corrected. The good thing is that it is a quasi "peer reviewed" information database so that wrong information can be corrected by one of the other contributors. I have already gone in an corrected a bunch of info but there is still a lot of wrong or misleading information out there besides the good stuff.

The pictures of your juveniles (last two pictures) look like juvenile dwarf shrimp/algae eating shrimp to me. Do you have some Caridina or Neocaridina species in that tank as well? Juvenile Palaemonid shrimp would still have very visible chelae (claws) and none of the shrimp you show on the pics has them.

bochr · Post by **bochr** » Wed Oct 12, 2005 9:55 am

The 5 Macrobrachium is the only shrimps in the tank.
The shrimplets must be Caridina sp. "Tiger" then. I moved my tigers from this tank a couple of weeks ago.

Post by **Mustafa** » Wed Oct 12, 2005 10:20 am

Mystery solved.

They are most likely Tiger Shrimp juveniles. Your Macrobrachium larvae probably died or got eaten. To raise them I would move an ovigerous female into a separate tank until the larvae hatch and then remove her.

bochr · Post by **bochr** » Wed Oct 12, 2005 10:35 am

Well that's pretty nice

because i only have 1 Tiger female left.

There's still one Macrobrachium female carrying eggs. I'll move her to an empty tank.