cross breeding

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DJ-don
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cross breeding

Post by DJ-don »

has any crossbreeding from any kind of catfish happened? i'm just a bit curious if it has happened
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Re: cross breeding

Post by Carp37 »

These two threads discuss hybridisation in Corydoras:-
http://www.planetcatfish.com/forum/view ... =6&t=26767
http://www.planetcatfish.com/forum/view ... =6&t=27029

Several pleco genera can produce hybrids- L10A is believed to be a hybrid Rhineloricaria, and Ancistrus bristlenose are believed to hybridise.

Plus there are all the man-made (with artificial fertilisation of eggs) hybrids- redtailed cats X tiger shovelnose, redtailed cats X Oxydoras, Synodontis species hybrids by the bucketful...
Megalechis thoracata, Callichthys callichthys, Brochis splendens (and progeny), Corydoras sterbai, C. weitzmani, CW044 cf. pestai, CW021 cf. axelrodi, Pterygoplichthys gibbiceps, Ancistrus cf. cirrhosus (and progeny), Panaque maccus, Panaque nigrolineatus, Synodontis eupterus
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Re: cross breeding

Post by Richard B »

DJ-don wrote:has any crossbreeding from any kind of catfish happened? i'm just a bit curious if it has happened
This has happened many times by man's intervention, with many species :evil: either by the fact of housing species in restricted environments ie- tanks & having it occur naturally (which is unusual, depending on how closely related the sp are) or by intentional design. If you look in cat-e-log you can see examples of pims & syno hybrids. There are even some bizarre hybrids coming out like pang x RTC or TSN x O niger, or pang x clariid!!!!! I wish with all my heart man would step away from these abominations.....

I also believe there are records of wild occurrances of close related sp but these are very rare
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Re: cross breeding

Post by Bas Pels »

Although I detest keeping hybrids, I do see advantages in keeping them commercially

Imagine a fish farmer who has onds close to a river, but the river does not contain farmable catfish. If he starts breeding some catfish, the result will be the species finally excapes - through waterchanges, or other accidents. A new species is introduced, and a disaster might happen

Much better the farmer grows fish which are sterile, being infertile hybrids. On a side note, many species start breeding young, and therefore waste a lot of energy reproducing. The resulting better crop might even undo the cost for buying fish (I know breeders of Tilapia, Oreochromis mossambicus or niloticus prefer the hybrid above breeding their own stock)
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Re: cross breeding

Post by DJ-don »

after looking at these topics, why are people saying that you should stop cross breeding when you can just not sell them and just keep them in your tank? its just like what happened with all the dogs. there is a high amount of crossbreed dogs and there isn't that much contreversy. why can't we just make nature take its course and just not sell them?
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Re: cross breeding

Post by Richard B »

Hybrids are created for 2 purposes (mainly, & please correct me if i'm wrong)

1 - food

2 - selling in the aquarium trade to make lot's of money

As for synos - how would you feel if you paid a couple of hundred pounds for a rare species & then found out it was a cross bred hybrid - not happy i can tell you!

Dumb question of the day - are all hybrids sterile? What about sturisoma?

Also there is a hybrid syno spawning video on youtube - i don't imagine young were raised from those...
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Re: cross breeding

Post by DJ-don »

Richard B wrote:Hybrids are created for 2 purposes (mainly, & please correct me if i'm wrong)

1 - food

2 - selling in the aquarium trade to make lot's of money
i get number 2 but what do you mean by food? to give to bigger fish to eat or to feed on eggs?
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Re: cross breeding

Post by PlecoCrazy »

I had a L260 and a L46 cross and it produced a very cool fish. I figured the way different color pattern between the two would have prevented it but it didn't. The fry look really cool, I'm sure all sorts of people would want to buy them but its not right. Once I discovered I had hybrid's I put an end to that love affair. I didn't sell any and they are in a discus tank. I agree you can keep them yourself and not sell. You should try to prevent it but if it happens and you got a cool fish then keep it. But if you allow the hybridization to continue you are going to wind up with more fish than you know what to do with and then what. Doubt you'll want to kill them so you'll give them away or sell them and then the problem has gotten to what everyone is complaining about. Beyond that, say the fry of my (I call them them the QueenKings) actually happen to reproduce in the tank they are in. I'm going to be in a worse spot than I am now. Then I'll have F1 hybrids that I have no more room for and can't sell or give away, plus a breeding group of hybrid fish that I have no where to separate so they'll keep reproducing and then what, I'm screwed and either have to kill them, sell them or give them away. Don't worry I won't do the last two but I hope I never get in that spot.

So my bottom line is hybrids are wrong and should be avoided when possible. Sometimes things happen that we don't plan on and we get some hybrids but once we know what is going on we need to put a stop to it.
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Re: cross breeding

Post by Suckermouth »

DJ-don wrote:i get number 2 but what do you mean by food? to give to bigger fish to eat or to feed on eggs?
People breed hybrids for aquaculture for people to eat.
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Re: cross breeding

Post by jerry58 »

Hi PlecoCrazy
I had a L260 and a L46 cross and it produced a very cool fish.
I am on another site trying to find out if L46s can be cross bred with other fish to produce nicer looking fish and came across this,what a coincidence.
I am getting no answers on that site so just out of curiosity have you any pics of the fish to support your claim I don't doubt you just interested to what they look like.

Just for the record I do not support breeding hybrids in any way.

Thanks jerry
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Re: cross breeding

Post by PlecoCrazy »

Here is the post from when it happened. I thought I had zebras but later found out not. I'll post some pics later on tonight.

http://www.planetcatfish.com/forum/view ... =5&t=14071
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Re: cross breeding

Post by Shane »

its just like what happened with all the dogs. there is a high amount of crossbreed dogs and there isn't that much contreversy.
Not the same thing at all. All domestic dogs are one species, Canis lupus familiaris, so they are not crossbred. Crossbred usually refers to the crossing of two different species. To crossbred a dog one would have to cross it with a jackal, fox or coyote. Crossing a dog and a gray wolf would not be crossbreeding as they are the same sp. Hope that sheds some light on what aquarists mean by "crossbreeding."

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Re: cross breeding

Post by DJ-don »

thanks with all the comments guys but can crossbreeds breed with;
e.g. a panda cory with corydoras paleatus crossbreed breed with a normal peppered cory and/or panda cory?
or could they only breed with their own hybrid kind?>
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Re: cross breeding

Post by MatsP »

In some cases, hybrids are sterile. Most (if not all) mammal hybrids are sterile, whereas some fish are KNOWN to NOT be sterile, and others are unknown whether they are sterile or not.

We know that L10a not only breeds, but also breeds to look the same.

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Re: cross breeding

Post by PlecoCrazy »

I posted the pics of the L46/L260 on my original post of the event. They are coming up on three years old and there are around 10 of them so I'll probably be finding out in the next year whether they reproduce or not. I'm hoping not but we'll see.
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Re: cross breeding

Post by Suckermouth »

PlecoCrazy wrote:I posted the pics of the L46/L260 on my original post of the event. They are coming up on three years old and there are around 10 of them so I'll probably be finding out in the next year whether they reproduce or not. I'm hoping not but we'll see.
Considering the relatively close relationship among Hypancistrus species, my guess is that they will be fertile... Those fish look rather interesting, though.
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Re: cross breeding

Post by apistomaster »

How do we know whether or not many of the Hypancistrus spp. found in nature, say those of the Rio Xingu, are not actually hybrids between fewer species than we currently believe are endemic to that river? There are many forms that appear to be intermediates between better defined species. The genus could still be in considerable flux, especially those from the same or nearby streams. It would explain why it is often so difficult to identify many of them.
It looks to me like many Hypancistrus spp are are recent, in geological time, and still very much undergoing radiative speciation.
The reproductive barriers between species appear to be low. Low enough to question whether or not there are as many species as there are Hypancistrus L-numbers.
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Re: cross breeding

Post by MatsP »

apistomaster wrote:How do we know whether or not many of the Hypancistrus spp. found in nature, say those of the Rio Xingu, are not actually hybrids between fewer species than we currently believe are endemic to that river? There are many forms that appear to be intermediates between better defined species. The genus could still be in considerable flux, especially those from the same or nearby streams. It would explain why it is often so difficult to identify many of them.
That would partly depend on the particular definition of species. If we assume the mammal method of "they produce viable offspring", then I expect all Hypancistrus can be lumped into a single species. I don't think anyone on this forum follows this particular definition, but that would be the only simple and strict rule one could apply. We get into a much less clear area of taxonomy when we start discussing "how much different does it need to be to be a species".
It looks to me like many Hypancistrus spp are are recent, in geological time, and still very much undergoing radiative speciation.
The reproductive barriers between species appear to be low. Low enough to question whether or not there are as many species as there are Hypancistrus L-numbers.
Yes. L-numbers are NOT species - as I'm sure you are aware - but rather a pseudo-species definition. And there are no strict rules as to what encompasses a new L-number and what doesn't - the same species of fish, from the same river could very possibly have different L-numbers simply because one specimen (or group of specimens) is exported from Colombia, and the other from Peru, Venezuela or Brazil - even if all the fish were caught on the same day, lumped together, and only split at the "distribution central" where the fish are collected together before shipping to the epxorter proper... By scientific measures, that's OBVIOUSLY not two different species. But since exported fish's capture locality is often vague or non-existant, export location is a much easier measure to use to define where they are from.

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Re: cross breeding

Post by DJ-don »

after looking at Apsitomaster's post, i was starting to think.... how do we know, the fish that we manage to catch in the wild arent just crossbreads at all? for all we could know, an l204 could be combine of other panaque species.
for example, the crossbred fish that plecocrazy managed to do, how do we know if these fish exist in the wild? for al we could know, right now fishermen might just've snagged a few of the crossbreed L46 and L260
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Re: cross breeding

Post by DJ-don »

and also how could 2 different species crossbreed in the first place?? the 2 fish must hav the same kind of dna or something (not really sure on which it is dna genes etc :P)
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Re: cross breeding

Post by Janne »

Larry wrote:How do we know whether or not many of the Hypancistrus spp. found in nature, say those of the Rio Xingu, are not actually hybrids between fewer species than we currently believe are endemic to that river? There are many forms that appear to be intermediates between better defined species. The genus could still be in considerable flux, especially those from the same or nearby streams. It would explain why it is often so difficult to identify many of them.
It looks to me like many Hypancistrus spp are are recent, in geological time, and still very much undergoing radiative speciation.
The reproductive barriers between species appear to be low. Low enough to question whether or not there are as many species as there are Hypancistrus L-numbers.
Even without any special knowledge within systematic I do agree with you, special the area from Altamira downstreams couple of miles north of Belo Monte. If we start at Altamira, we will find a few species with quite good distance between each of them (Hypancistrus) the more north and closer to Belo Monte the more "species" we will find and both south and north of Belo Monte you find many different L-numbers of Hypancistrus at the same locality. Around Belo Monte you find L46, L66, L173, L236, L333, L399, L400, L287 and L345 is mysterious... probably mixed up with other L-number of the guy that put these L-number. What is called Hypancistrus sp "Lower rio xingu" in the Cat-eLog is also from the same area around Belo Monte.

The only species that have several other localities of these above is L46, L66, L236 and L333, the first two is found upstreams almost to Altamira and there we find L174 also together with a mimic Hypancistrus species lacking any L-number. At the mouth of Rio xingu at Porto de Moz we find L236 and L333, no other known Hypancistrus. If I would be an scientist working in this field I would call this area between Altamira and Belo Monte for a "Hot spot", where natural crossbreeding and natural creating of new species is comparable with the hot spots in some coral reafs in the pacific. To use DNA barcoding for these species I think will be impossible, to close relationship between them.

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Re: cross breeding

Post by Janne »

Mats wrote:That would partly depend on the particular definition of species. If we assume the mammal method of "they produce viable offspring", then I expect all Hypancistrus can be lumped into a single species. I don't think anyone on this forum follows this particular definition, but that would be the only simple and strict rule one could apply.
It's almost impossible to compare with mammals, mammals have so many subspecies and in this case Loricarids has no subspecies at all, a Lion from Africa pairing with a Lion from Asia will probably get fertile offspring's or a Tiger from Siberia pairing with a Tiger from Sumatra. Different species of Zebras will probably also get fertile offsprings and so on.

If you crossbreed different Ancistrus species, different Peckoltia species or different Hypancistrus species with each other within the same genus, at least these species with not to large differencies (distances) I presume would produce fertile offspring's. I think the "mammal method" only tells you if 2 different species belongs to the same genus and that these 2 can crossbreed with fertile offspring, if 2 different genus produce offspring's I call them hybrids and they are normaly not fertile... thats my mind and not any science so I can be wrong ;)

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Re: cross breeding

Post by Suckermouth »

Before we get too far, there is a difference between "viable" and "fertile" offspring, and the traditional definition has been "fertile", not "viable". Viable but infertile offspring still would allow biological and genetic separation of two groups into species.
DJ-don wrote:and also how could 2 different species crossbreed in the first place?? the 2 fish must hav the same kind of dna or something (not really sure on which it is dna genes etc :P)
This is correct. It is possible for two species, especially closely related species, to have DNA that is similar enough to produce fertile offspring.
Janne wrote: Around Belo Monte you find L46, L66, L173, L236, L333, L399, L400, L287 and L345 is mysterious... probably mixed up with other L-number of the guy that put these L-number. What is called Hypancistrus sp "Lower rio xingu" in the Cat-eLog is also from the same area around Belo Monte.
Wow, that is actually quite a few types to find in one locality. It's interesting that there are even that many phenotypes in just one location of such closely related fish. I agree that the genetic distinction between them is likely difficult to see as these species are likely recently diverged; perhaps entire-genome comparisons would be necessary, rather than single gene comparisons as in DNA barcoding.
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Re: cross breeding

Post by Mike_Noren »

Interbreeding and producing viable offspring is a primitive (plesiomorphic) trait; it has zero bearing on whether two groups of animals are the same species or not.

INability to interbreed and produce viable offspring is however a derived (apomorphic) trait, and indicative that two groups of animals are different species.

Moderately exaggerated: ability to produce fertile hybrids mean nothing, inability to produce fertile hybrids means different species.
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Re: cross breeding

Post by apistomaster »

To put a finer point on what I was suggesting is not that wild hybrids are common but that the Hypancistrus we have L-numbered that are from the same river system or adjacent ones, I suspect represent many fewer species with naturally occurring wide variations in patterns and colors. I doubt there are any biological barriers preventing variants from interbreeding but by my definition of a species, two different species that evolved in the same range would rarely interbreed in the wild.

Anything can happen in an aquarium so do not be quick to generalize that to what happens in nature. Inductive reasoning is best left in mystery stories and left out of science.
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Re: cross breeding

Post by Janne »

Milton wrote:Viable but infertile offspring still would allow biological and genetic separation of two groups into species.
Only with the help of a human I suppose, if happen in nature these offspring's would extinct them self.
Milton wrote:Wow, that is actually quite a few types to find in one locality. It's interesting that there are even that many phenotypes in just one location of such closely related fish.
Yes, quite interesting I think but maybe not totally impossible if you consider that the whole stretch between Altamira and Belo Monte is more or less rapids and waterfalls, offspring's from species reproducing uppstreams either they want or not will be flushed with the current down to Belo Monte... after Belo Monte no rapids just a very large lake.

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Re: cross breeding

Post by Janne »

Larry wrote:two different species that evolved in the same range would rarely interbreed in the wild.
This happen every year in many coral reafs, why not in some few extreme places like the rapids between Altamira and Belo Monte? It's not only the pattern that is variable within Hypancistrus from Rio xingu, body shape, head shape and size and colour of their eyes. 99% of all Hypancistrus from Rio xingu was collected between Altamira and Belo Monte when they was allowed.

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Re: cross breeding

Post by Suckermouth »

Janne wrote:
Milton wrote:Viable but infertile offspring still would allow biological and genetic separation of two groups into species.
Only with the help of a human I suppose, if happen in nature these offspring's would extinct them self.
My point exactly. Species would remain separate as those hybrids would not reproduce.
Janne wrote:
Milton wrote:Wow, that is actually quite a few types to find in one locality. It's interesting that there are even that many phenotypes in just one location of such closely related fish.
Yes, quite interesting I think but maybe not totally impossible if you consider that the whole stretch between Altamira and Belo Monte is more or less rapids and waterfalls, offspring's from species reproducing uppstreams either they want or not will be flushed with the current down to Belo Monte... after Belo Monte no rapids just a very large lake.

Janne
Now I'm very interested. That is fascinating. Separate rivers would allow separation of species but the collection of various, closely related species in a lake could cause species to intermix. Cool. But what you are describing is a source of species and a sink of species, which is pretty interesting.
apistomaster wrote:To put a finer point on what I was suggesting is not that wild hybrids are common but that the Hypancistrus we have L-numbered that are from the same river system or adjacent ones, I suspect represent many fewer species with naturally occurring wide variations in patterns and colors. I doubt there are any biological barriers preventing variants from interbreeding but by my definition of a species, [if] two different species that evolved in the same range [then they] would rarely interbreed in the wild.
Not to derail the topic since this isn't related to the point you're trying to make, but so far as we know, there is very few known examples of Neotropical fish species that have evolved in sympatry. In other words, there are almost no two different species that have evolved in the same range. Examples of related species being in the same place are as a result of evolving in separate ranges and rejoining. Also, related species of the same genus in the same place are rarely each other's closest relatives. Unfortunately, since the "if" clause of your statement isn't fulfilled, your "then" clause is irrelevant (I put brackets in your quote to indicate where those would be).

It may be possible that there is a wide variation in single species of Hypancistrus, but it may also be possible that they are populations that have been separating for some time now. It is difficult to say.
Last edited by Suckermouth on 10 Oct 2009, 04:54, edited 1 time in total.
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Re: cross breeding

Post by apistomaster »

Hi Janne,
What you say about many reef fish is true although I would say their are extenuating circumstances involving the peculiarities of how many reef fish spawn that makes hybridization more frequent than among fresh water fish. Many Chaetodon, Pomacentridae Angels, to chose a few examples, spawn at dusk, en masse and do not practice brood care. The chances of random cross fertilization are very much higher between related species spawning simultaneously in the same immediate vicinity.

In the Hypancistrus, there is a more elaborate courtship phase which would seem to me to help reduce the chances of random hybridization.
Only more information can tell us whether or not the Rio Xingu Hypancistrus species found between Altamira and Belo Monte actually frequently hybridize. If these fish do hybridize frequently then I would say the definition of which are species and which are merely variations needs refinement. If there are many different color forms crossing in the wild, then I would argue that is much like the situation with Symphsodon haraldi where color variation is the rule and interbreeding among color variants is not hybridizing between species.
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Re: cross breeding

Post by Janne »

Larry wrote:What you say about many reef fish is true although I would say their are extenuating circumstances involving the peculiarities of how many reef fish spawn that makes hybridization more frequent than among fresh water fish. Many Chaetodon, Pomacentridae Angels, to chose a few examples, spawn at dusk, en masse and do not practice brood care. The chances of random cross fertilization are very much higher between related species spawning simultaneously in the same immediate vicinity.
Yes I know, but my point is; why cant similar hot spots exist in freshwater even if they are very rare.
Larry wrote:In the Hypancistrus, there is a more elaborate courtship phase which would seem to me to help reduce the chances of random hybridization. Only more information can tell us whether or not the Rio Xingu Hypancistrus species found between Altamira and Belo Monte actually frequently hybridize.
Yes they have a totatlly different reproduction behaviour, if there are any natural crossbreeding in Rio xingu it's around Belo Monte, not upstreams at all... just one area. If species offspring's upstreams follow the current and rappids downstreams they will somewhere be gathered together... right? At this locality there are a mix of species and of reasons we don't know yet but they interbreed with each other, there can be many reasons; for example the population of all these Hypancistrus is so high that they marely can avoid each other, one sex can be over represented, opportunistic reproduction when keeping several species in aquarium is not a question if it will happen... it's just a question of time, the same in nature if the population is to high at the same locality.
Milton wrote:Now I'm very interested. That is fascinating. Separate rivers would allow separation of species but the collection of various, closely related species in a lake could cause species to intermix. Cool. But what you are describing is a source of species and a sink of species, which is pretty interesting.
Yes, it should make anyone working in this area excited.

Janne
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