CORYDORAS VENEZUELANUS-Was it bred in captivity?

[cartouche]

I just bought a group of Corydoras venezuelanus (or Corydoras sp. Venezuela). I had no idea that a Corydoras of this sort exists. The fish were so nice that I took them despite high price. Don't you know something about this fish? Was it bred in captivity at all?

[cartouche]

I checked info on this site http://www.planetcatfish.com/catelog/sp ... ies_id=716
and it seems that they can be spawned. Does anybody have personal experience with this species?

[kim m]

I have a breeding group. They are fairly easy to spawn. I keep them in tap water for a month or two (in my stock tank) and then move them to a small tank with rainwater. Usually they spawn the next day. Temperature is around 24 degrees celcius.

The fry seems rather delicate though, and I've never been able to raise more than 10% of the fry despite a 100% hatch rate. Trying out other raising methods to get a better result though. I've found that bare bottom tanks don't work for me when raising these fry.

[Coryman]

I first discovered and bred this species in 1999. It is a natural species and was put into synonymy with C. aeneus by Nijssen & Isbruecker in 1980. However I along with many others believe it is a true species in its own right.

Ian

[corywink]

Wow, beautiful colours and nice and chubby.

[cartouche]

I have a breeding group. They are fairly easy to spawn. The fry seems rather delicate though, and I've never been able to raise more than 10% of the fry despite a 100% hatch rate.

I expected exactly something like that. I already know the insidious forces of nature Virtually every nice fish is either hard to spawn or hard to raise. In this case (a possible natural crossbreed of C. aeneus x C. duplicareus???) I expected easy spawning, but difficult raising - as it is with C. duplicareus. By the way, with what do you have the biggest problems? Do they die during the larvae stadium, or during the first weeks of life?

[kim m]

I expected exactly something like that. I already know the insidious forces of nature Virtually every nice fish is either hard to spawn or hard to raise. In this case (a possible natural crossbreed of C. aeneus x C. duplicareus???) I expected easy spawning, but difficult raising - as it is with C. duplicareus. By the way, with what do you have the biggest problems? Do they die during the larvae stadium, or during the first weeks of life?

I think your "natural hybrid" theory is somewhat far out in the bushes. C. duplicareus is not present in Venezuela as far as I'm aware. Also, a cross breed of these two species would be likely to grow a fair bit larger than C. venezuelanus.

The fry dies between 2 and 4 weeks of age.[/quote]

[Shane]

I have collected 1,000s of these in Venezuela and, like Ian, am sure that they are a distinct sp. Actually there are two distinct fish. C. venezuelanus is restricted to the Lake Maracaibo, Rio Tuy and Rio Guapo drainages. These drainages were all connected historically and share about 90% of the same spp between them. Also, note that these drainages are all on the northern side of the Andes. If you cross the mountains and get into the llanos drainages, you encounter a similar but different fish that I call C. cf. venezuelanus "llanos." Don Kinyon collected both spp with me, took them back to the States and spawned them. As would be expected, their spawning details (size and number of eggs especially) were very different.
C. venezuelanus is found in clear foothill streams that rarely get warmer than 76F and have a good amount of current (to give an idea of the temp and current, you can also catch Chaetostoma in these streams). They are found in the slower creek sections over sand and small stones. They share their habitat with Ancistrus brevifilis, Farlowella acus, Rineloricaria, Chaetostoma, and diamond tetras. The predatorsare pike cichlids and hoplias tetras.
-Shane

[cartouche]

Thank you very much for sharing your experience and info. Could you also tell me something about their productivity (number of eggs) and growth?

By the way, what's their adult size? 5,5 cm? I bought very small fish, 2,5-3 cm. They are very active and steadily looking for food. Since they come from the hills, I think that I should keep good water conditions. Or do you think that they are not extra sensitive to water quality?

[kim m]

Shane, I didn't know that there were two fish that looked like this. Do you have some info to separate them (you mentioned egg count as an example of the differences).

It would be nice to know wich one I have

[Shane]

Kim,
Both look fairly similar right after capture, but the sp from the llanos is smaller. It is captured alongside C. habrosus and C. septentrionalis. In the range of the proper C. venezuelanus (Maracaibo, Tuy and Guapo), it is the only cory sp found. The big difference is that after the llanos form settles in it turns a very dark color overall with some orange highlights on the shoulder. As the true C. venezuelanus settles in it changes from a mettalic green to a pinkish color with a dark shoulder blotch.
-Shane

[kim m]

So, if my fish are greenish with orange on the shoulder, it's the "sp." and not the "real" one?

Attached picture is of my breeding group. None of the fish is more than 4½ cm. TL.

[img]http://www.onlinenu.dk/mathiasen/i ... .jpg[/img]

[mummymonkey]

Corydoras sp. "Venezuela" is surely preferable to Corydoras venezuelanus. Especially confusing if it's in italics.

[Shane]

Corydoras sp. "Venezuela" is surely preferable to Corydoras venezuelanus. Especially confusing if it's in italics.

I can not see how C. sp "Venezuela" would be the preference since 1) C. venezuelanus is very, very likely a valid sp and 2) C. sp "Venezuela" would imply that they fish had never been scientifically described and we do not know where it comes from (other than Venezuela). Neither is correct.

The fish has been described and has a very clearly defined range and habitat. I guess we could call it C. sp "distinct species from the Tuy/Guapo/Maracaibo drainages placed as a junior synonym to C. aeneus by European scientists that have never actually collected the fish in the wild, done comparative population studies, nor mapped the fish's range."

Kim, yours are straight C. venezuelanus although I can not ID the exact creek. The llanos form is black all over with the orange shoulder.
-Shane

[kim m]

Thank you Shane, nice to have that sorted out

[Shane]

Here are the two forms. I believe they likely represent two spp.

C. venezuelanus from the Rio Tuy proper. Note that the holotype was from the Lake Maracaibo population, but these look more similar to Kim's fish. The Maracaibo population has a slightly larger shoulder spot.



The llanos form


-Shane

[cartouche]

Hmm, they are more delicate than I thought. I bought six and after 4 days, two are already dead. They are tiny and really don't look like hardy fish. If I lose another one, I will probably get rid of them. Breeding sensitive fish of this sort makes no sense for me.

[Coryman]

I found them to be moderately easy to breed and raised several hundred over a couple of years.

Can't see the point of you trying to breed fish if you are going to give up at the first little obstacle. A little patients is needed along with perhaps a couple of alterations to the environment you keep them in. They are not a week species, far from it, they are quite tough.

Ian

[cartouche]

Perhaps it was my fault, because I placed them in too old water after I came home (after 11 hours) from Vienna. I changed 30% of water content in the tank before I placed them there, but it may have been too little. However, 3 years ago I already travelled one hour more with 10 Duplicareus and I lost none.

Remember that my patience is not an issue here. I simply don't want to breed (and then sell) expensive delicate fish to people. I don't want to get emails like "Hey, the fish died. I want my money back!" Recently I bought eight pieces of L-129 (no cheap purchase, really) and after 14 days, they began to die from some unknown reason. Within three days I lost all eight and I still don't know why. Now I have 23 little Sterbai in the same tank (I want them as breeding fish in the future), in the same (or even worse) conditions and they don't betray any signs of discomfort even after several months. Now I understand, why so few people are interested in breeding L-numbers. I know three breeders, who had Hypancistrus zebra and they all lost adult fish from some reason. They subsequently gave it up, because it simply wasn't worth the effort.

But if you think that they are not extra sensitive (contrary to what "Kim M" said, at least about fry), I will try to contact the shop owner, if they have any more pieces. They are very nice and still hard to get, and four pieces is too little.

[kim m]

I should add that raining the fry in the spawning tank with sand bottom and javamoss seems like a good idea, instead of using bare bottom tanks.

Lots of fry has survived longer than the last batch did in bare bottom tanks.

I think they are as hardy as Ian says. And as Ian also mentioned; patience is needed to find the right way to treat the fish correctly.

[HaakonH]

Cartouche:
Usually if such deaths occur it's due to some sort of illness in your fish -at least if you're sure the tank is functioning properly and the water values are ok. L-numbers are often plagued with internal parasites and suffer from bacterial infections (or starvation/stress) which easily cause them to die soon after purchase. It really depends on the condition of the fish when you buy them. L-numbers in good condition are tough fish unless you put them in an environment that's way off what they require.

Kim:
A bare-bottom tank often kills your fry because of the layer of lethal bacterias on the glass, which the fry pretty much lives on/in. A thin layer of sand keeps the fry from plowing through the bacteria layer, as these bacterias are broken down by the biological fuction of the substrate -basically a thin layer of substrate gives the tank a cleaner environment:)

[cartouche]

I can't imagine raising fry in a tank with bare bottom. I tried it once - and I will never repeat it again. It makes much more problems than it solves. But do what you want, if it's according to your gust. I have never had any problems with such a dying of fry, because I clean the bottom of the tank regularly.

As for L-numbers, I naturally know all the problems that surround freshly imported fish. But I rather think that it was some problem in the water. If they suffered from parasites or starvation, they would die gradually and not suddenly within 3 days, after 14 days in the tank. But it is true that they were always hidden under a root and didn't eat much. The uneaten food then lay on the bottom, although I tried to remove it regularly. Water had 0,10 mg NO2/L during the whole 14 days, which is not ideal, but it shouldn't hurt them. Ironically, they started to die three days after a 30% water change.

[mona o]

Bare bottom tanks demands cleaning often:)

After a couple of days bare bottom tanks (=BBT) develop a thin layer or film of almost invisible "slime" and bacteria. This can be deadly for the fry if left alone. It must be CLEANED.

I clean my BBT fry tanks every second day with very warm water, scrubbing them thoroughly with a piece of white filter wool/wadding. Rinse well in hot water too. I have two identical plastic tanks, and move the fry between them when it's time to clean one.

With this method I have so far had a survival rate between 60 and 100 % on my broods (C. adolfoi and C. sterbai).
Right know I have about 70 C. adolfoi fry, ranging from two weeks of age up to 9 months. I change 99% of the water dayly, and I'm using clean tap aged water (adjusted temperature and with an airstone).

I read an article about breeding Corydoras adolfoi once,written by an american man. He wrote something I've kept in mind since then because it so true :

"Cleanliness is next to Godliness when raising catfish"

[cartouche]

I actually wanted to say "I can't imagine raising fry in a tank withOUT bare bottom."
But I think you take it too pedanticly. It doesn't need such complicated operations like changing 99% water every other day. You will gradually learn the right flair to handle with fry. When I started breeding Sterbai, I was able to keep alive 50% fry maximally. Now my loses of Sterbai fry don't exceed 10-15%. The slim can be removed with a foam scraper and the water with the floating remains should be sucked out.

By the way, I bought another six pieces of Venezuelanus and they are fine. The two loses were obviously my fault, because I gave them into too old water.

[ghostsword]

These are mine, they breed fine on the tank.

They are slightly darker, but the shoulder is redder as well:

rush hour panorama by GHOSTSWORD, on Flickr


DSC_2088 by GHOSTSWORD, on Flickr


DSC_2078 by GHOSTSWORD, on Flickr

[Vlacek]

Hi. Just wanted to report breeding of c.venezuelanus. I have a group of five, definitely two females, probably three. They are spawning in my display tank at water cond. temp 24C, dGH=7, dKH=6, pH=7-7.5. No special treatment to get them spawned. They always lay eggs between 9AM and noon local time, batch is roughly between 50-80 eggs. Quite bad fertilization ratio - cca 10%. Eggs are usually on the tank walls and on valisneria leaves, sometimes on the heater and anubias. I now probably have like 20 fry of different age and size (between 5mm and 12mm). I feed them twice a day with SERA Micron powder food and frozen sea rotifers (no idea about exact name). Some are almost three weeks old so I hope I'll manage to raise them further. I have left them in the main tank with parents and other fish. I moved some eggs to small breeding tank but none of the fry survived for more than a week, not sure why. Parents don't seem to pay any attention to eggs at all, not like pandas. I'll post some pictures once I process them.

[bsmith]

I really like the llanos form, they remind me of my black schwartzi.

I find the harder the fish is to breed whether difficulties lie in keeping the specimen alive, recreating a habitat conducive of breeding or rearing fry, the more rewarding it is when I have success.

It took me 2.5y to get my L183's to breed but when they did it sure was wonderful!

[Vlacek]

Ilanos form looks nice but the one attached to the post which started this thread is also nice and that is the one I have. However, these cories change color with mood and water conditions a lot so to get the picture of them in full color (especially nice orange) is quite difficult and rare.

[Vlacek]

Finally some pics...

[Stuey]

Hello All,

Does anyone know if there are any of these Cories available for sale in the uk at the moment, been checking various stocklists, but not found any yet

Many thanks
Stuey