Petshrimp.com Discussion Forum

Just to inform people here that blue freshwater shrimps do exist, at least to a certain extent. They belong to the species Atyaephyra desmaresti, a species that is wide spread all around the Mediterranean sea but also in the north of Europe up to Germany where its occurence has been recently mentioned. In fact, "blue shrimp" is a little bit too much for the species as a whole, because only certain specimens are really blue (they are however quite frequent, e.g. about 50% in my tank are blue), the others are redish.
Here is a picture of one of my own specimen (I know it looks greenish but this is due to the low quality of the pictures taken by my digital camera in the darkness; it is dark blue in reality):

This specimen has been collected in a small lake in southern France as all the specimens I have.

Interesting. Most specimen I have seen of this shrimp were not blue, but they were also all caught in Germany. Maybe different populations have different color variations. The question is if the blue is caused by environmental factors or by genetics. The problem with these shrimp is that they are extremely hard to breed in captivity. They seem to only carry eggs once a year and in order to produce eggs they seem to need a "cold period" (to emulate a "winter") as they are temperate zone animals with a seasonal breeding cycle. Plus, they produce tons of little larvae the size of Caridina japonica larvae (or even smaller), and although the larvae can be grown in complete freshwater, they are not easy to grow due to their tiny size.

I would not mind giving these guys a shot at some point, though, as I have not had personal experiences with them, yet.

I had some but just managed to breed them once. youngs tend to be more pale and brownish, even kinda transparent.

The adults seem to take different colors from reddish to bluish like in the photo. I do not think it is genetics but I have no scientific data to prove it.

Cheers,
Pedro

milalic wrote:I had some but just managed to breed them once. youngs tend to be more pale and brownish, even kinda transparent.

The adults seem to take different colors from reddish to bluish like in the photo. I do not think it is genetics but I have no scientific data to prove it.

Cheers,
Pedro

Young specimens in my tank are indeed transparent. Adults are more colorful as you notice. It is hard to tell if it is genetically or environmentally induced. In my opinion, it is both. Indeed, I have specimens collected the same day in the same area and some of them are reddish and others are bluish. However, they have much more colors since I have introduced them in the tank. I believe the color is genetically induced but the degree of coloration (from red, blue or yellow spots to completely and homogeneously red, blue or yellow) is influenced by the environment. For a single specimen, spots are all of the same color (they are no mixed coloration).
I have several friends here in southern France who also possess specimens of this shrimp in their tank. They all told me this shrimp is easy to breed and that they have several hatchings every years. No need for a cold period in the year. In the opposite, they seem to appreciate warm water and reproduce more frequently than in their natural habitat. This difference with your observation Mustapha probably stems from teh fact they don't come from Germany but from southern France, where winters are quite warm. I don't know if in their natural habitat these specimens coming from southern France only reproduce one time per year but in a tank, it is sure they do it several times/year.
Will keep you informed of my personnal experience with these shrimps.
I benefit from this post to congratulate Mustafa for his really excellent website. I just regret that we (french people) don't speak english very well and thus, we cannot share more often our experiences with our friends from teh other side of the Atlantic ocean.
Best wishes,
B.

Hi Barracouse,

Thanks for the additional information. I only received my information from friends I have in Germany who keep this shrimp. Unfortunately, I do not have first hand (i.e. personal) information, yet. That's why it's very valuable that you are sharing information here.

Just a few questions. Did your friends actually manage to raise the young in their tanks to adulthood? Or are they just reporting that these shrimp carry eggs several times a year without having raised any young in their tanks? Have you seen any larvae in your tank yet? How many eggs do you think they are carrying? Some people in Germany claim that they carry over a thousand eggs. That seems like a lot of eggs for such a small shrimp if true.


Even the fact that they carry eggs independant of cold periods is very valuable, as this could mean that the people trying to breed these shrimp in Germany are doing something wrong but attributing their lack of success mistakenly to the alleged seasonal breeding pattern of this shrimp. Such things happen, as it is quite hard to isolate the exact reasons why your shrimp are not breeding...especially with species about which there is not much information available.

Barracouse wrote:I just regret that we (french people) don't speak english very well and thus, we cannot share more often our experiences with our friends from teh other side of the Atlantic ocean.

I think your English is excellent and if most other french people speak english like you, then I would encourage shrimp keepers in France to participate in this forum and share their experiences. Diverse experiences from all over the world are very important for all shrimp keepers. Unfortunately, due to the fact that everyone speaks a different language, most shrimp keepers in such countries as France, Germany and Japan cannot communicate with people here in the USA, which is a pity.

Barracouse wrote: This difference with your observation Mustapha probably stems from teh fact they don't come from Germany but from southern France, where winters are quite warm.
B.

In Portugal we have this shrimp too! I think this shrimp is originary in "All Europe"

The shrimp is originally from the mediterranean area but spread northwards into central Europe over the last few decades.

Mustafa wrote:The shrimp is originally from the mediterranean area but spread northwards into central Europe over the last few decades.

Yes, I wish I had already precised this in my first post. My english is probably not as excellent as you thought
Concerning Atyaephyra desmarestii in Portugal,I think I have seen an article in the journal "crustacea" on this subject (I jsut precise this for the members in this forum who may have access to this scientific journal).
Concerning details on breeding of A. desmarestii: I have not received answers from my friends to your questions yet, but I think I have better. Two of my specimens display eggs below the abdomen. In fact, one of the two has already released the eggs today. I am really not an expert in breeding shrimps (I am scientist but my work concerns arthropods that got extinct about 250 millions years ago!!!) so every advices would be appreciated (be sure I will read everything I can on the subject in the next few days, especially on this website, but don't dare to remind me the important things I should not forget to get adults from these eggs).
Few remarks:
I have introduced these shrimps in my tank for two and half weeks. It seems they like my tank environment (especially the warm water: 24°C. according to my friends, it is an important parameter).
It is hard to determine the number of eggs per shrimp but at first sight, it seems obvious that the second specimen brings about twice the number of eggs of the first. Mustafa, you are probably much more used to counting eggs. Here are two pictures of the second "pregnant shrimp", one of them is enlarged version of the other, focusing on the eggs. Hard to count but you probably can tell if there seems to have more eggs than in other shrimp species.
Here are the pics (eggs are greenish, this specimen is about two centimeters in sagittal length, not as colored as others, of the reddish type):







Will wait for your advices,
Barracouse.[/img]

Looks to me to be pretty small eggs, almost like the Amano. That should mean you'll hve larva, not baby shrimp. Get some "100-200 micron" golden pearls ready to feed these with when you see the tail hangers. Be sure there are no fish in the tank.

Looks like your shrimp is carrying several hundred eggs. My estimation is that there are at least 200-300 eggs on that shrimp. My advice would be to pack a tank will a lot of plants like Najas. If the tank is big enough, the larvae can feed on microorganisms that are already in and around the plants (i.e. infusoria, copepods, copepod naupli etc.). But that won't be enough for so many larvae. So, as badflash suggested, you will need some kind of larval food. I would get something that's smaller than 100-200 microns, though, at least for the first few larval stages. 50 microns or below should work. 100-200 microns works well for Palaemonetes paludosus (americna glass/ghost shrimp) larvae, but those larvae are comparitively HUGE as they already hatch from very large eggs at a very late larval stage. Judging from the size of the eggs of your shrimp, their larvae will take much longer to develop into postlarvae...I'd guess 2-3 weeks minimum.

And finally, don't forget the frequent water changes. The more frequent, the better. Good luck!!

My 100-200 micron size was based on my experience with amanos which look to have eggs of comparable size and number. The larva can hold that size pearl, but the smaller size would probably be better.

badflash wrote:My 100-200 micron size was based on my experience with amanos which look to have eggs of comparable size and number. The larva can hold that size pearl, but the smaller size would probably be better.

Oh, I see. Well, if that size works, then that's fine, too. In other words, whatever attracts them and is small enough to be eaten can be used as food.

Would like to share this picture of another blue specimen from southern France (Languedoc). For a long time I thought this picture must have been touched up, but I'm starting to believe it's real.