L2464- is this a wild hybrid?

[Jimmyaulo]

Dear Pleco friends,

I have been discussing with my friends on whether the so called L2464 is a wild hybrid or it is a new individual type of Pleco. Any thoughts anyone? Million thanks!

[bekateen]

Is this what you're talking about?


(http://i15.photobucket.com/albums/a385/ ... z.jpg.html)

[catfishchaos]

I didn't think L-numbers were in the 4 digits...

Am I wrong?

[bekateen]

No you're not wrong. AFAICS, it appears that whoever invented this number simply took the numbers

L024

and

L064

and put them together, perhaps to insinuate that "L2464" is a hybrid between these two fishes.

For the highest L-numbers (and LDA-numbers) listed at PC, look here: Cat-eLog > Numbers > L-Numbers > L464+ and here: Cat-eLog > Numbers > LDA-Numbers > LDA096+.

[Jimmyaulo]

Yes bekateen, I have a link that has a few more photos.

http://ifish.org.cn/forum.php?mod=viewthread&tid=315

[PseudaSmart]

Jimmyaulo,
Thank you for the web page link. It helped to clarify your question. After running the page thru a translator I was able to get the overall content and tone of the article.

The simplest answer to your question is yes. Hybrids do occur in the wild when two genetically similar groups live in the same location mingle. This answer is simple and a bit vague because scientific terms usually have a different meaning when used in the hobby as compared to the professionals. I don't think it was your intent to restart the debate.

Overall the article was the author's attempt to establish a designation for large / jumbo Pseudacanthicus which did not fall into the current numbering system. If I read the article correctly he has information on 300 unique specimens spanning over 60 years in Hong Kong.

Here is a translated and highly abbreviated section of the article describing how the name was chosen:
　'There are a lot of people wondering why the L2464 L24 and L64 must be mixed species of fish? Why not be defined as a species? Such as books or even on a site known as L63 does not fit. it will be as hybrids, they seem to have a common features but too large, saying that they are less appropriate for the same species, but bold assumptions as hybrids, is able to explain the large individual differences.....outcrossing is already common in the artificial environment, such as L24XL25, L160XL600 etc., so hybridization is it is possible and in view of its characteristics....hybrids L2464 L24 and L64 is a positive solution......'

People have sent me similar photos of fish in the past taken at the rivers and also man made crosses (accidental or intentional).
Once I got into the article it was rather interesting and impressed by the authors devotion to documenting this narrow Pseudacanthicus creation. It was also interesting to see how the focus was on the body form and patterning of the fish rather than the color.

Thanks, I learned something new tonight.
Jim

[Jimmyaulo]

Thanks for the reply. There is still 1 point that we are wondering, since the import individuals have reached a certain amount, it is not like a fluke, can we think that there is a possibility that it is a new species instead of the hybrid of 24 and 64?

To discuss on the other side of the mouth, these individuals all have slightly different patterns, would this be a strong evidence that it is indeed a wild hybrid instead of a new species? The thinking behind is that if it is he same species, shouldn't it to have a more stable outlook and features?

My last question is: is there another example of known wild hybrid and has sustained a population?

Many thanks if you have more thoughts or sharing.

[PseudaSmart]

I didn't think you would go for the simple answer
I'll tell you what I do know and then let the experts weigh in.

A real world example of a hybrid would be a mule. It is a cross between a male donkey and a female horse. They have different numbers of chromosomes and therefore substantially different.

A reverse example would be the birds called sparrows. In the eastern USA there are different names based on their color pattern but are the same species.

Getting back to plecos, many people would like the term 'species' as a convient way to separate them by pattern and not the actual definition. Regarding Pseudacanthicus I can tell you that P. Leopardus (L600), L114, and LDA07s all have the same DNA but have different repeatable patterns. But because the 600s and 07s territories mix during the rainy season many of the pseudas collected have a mix of both 'traits'. This is why a clear cut Id is difficult most of the time. The 114s are further away and are easy to spot. So, do you think they should all be called P. Leopardus? Let the debate begin!

One last bit of information. I just received a P. Histrix a few weeks ago and the plan is to send a sample for DNA testing. Then we will know the difference between them.

I will leave any further questions to the experts.
Jim

[PseudaSmart]

Just read my last post again which proves the point that my answer is not that great.

Mules cannot reproduce on their own so they are not sustainable.
The cross of 600 and 07 does not give a repeatable pattern.

I do remember a tv program talking about a polar bear and grizzly cross. They called it a hybrid and left it at that.

Jim

[Mol_PMB]

The concept of a 'species' is a man-made idea and necessarily a simplification of the real world. In my belief the concept of species has not been applied consistently in different areas of the animal kingdom either.

If we tried to split up the human race as much as we have done with Corydoras catfish I wonder how many species of humans there would be?

When we're dealing with L-numbers as undescribed species then the concept is even more vague.

As an engineer (not a biological scientist) I wish everything was neatly defined and mathematically demonstrable. But the real world isn't that simple!

[shrimpkeeper222]

The concept of a 'species' is a man-made idea and necessarily a simplification of the real world. In my belief the concept of species has not been applied consistently in different areas of the animal kingdom either.

If we tried to split up the human race as much as we have done with Corydoras catfish I wonder how many species of humans there would be?

When we're dealing with L-numbers as undescribed species then the concept is even more vague.

As an engineer (not a biological scientist) I wish everything was neatly defined and mathematically demonstrable. But the real world isn't that simple!

As for human race, Im guessing it would be 1 species that is surviving at the moment homo sapiens.
I think for 2 animals to be different SPECIES it would take a certain amount of difference in their DNA. But different colors would be VARIATIONS.
E.g 2 similar looking birds of prey are Buzzard(Buteo Buteo) and Rough Legged Buzzard(Buteo Lagopus) and im guessing they are in the same genus because they have similar enough DNA and not just appearance, since the buzzard and the rough legged buzzard have both dark and pale phases which look VERY different. So I think species is indeed a man made idea, but it can, if done carefully and with enough info, simplify all living organisms. but Im not sure at all of this, it only a prediction.

[Jools]

If we are talking about a fish in which many are imported over a long time span then I think we are jumping to the hybrid conclusion too readily.

Jools

[Jimmyaulo]

Thanks all, much appreciated for the answers. I do tend to think it is a wild hybrid by hearing and seeing what I have come across. However, I have not had many other examples to say that there is a phenomenon or typical way of hybrid group development. I have another friend who said that he has seen a fair amount of wild caught l47xl81, where he observed variation in terms of the spot patterns but limited to all other features that have the l81/l47 elements.

Jools, would you mind to elaborate a bit more? For your interest we have seen imports to Hong Kong for about 8-10 years. The quantity has always been small, small meaning no more than let's say 50 pieces in each year.

[Jools]

Wild caught hybrids are very rare to see. If you're saying around 50 a year have been imported for around about a decade then that sounds like the collection of a specific locality, probably by a specific exporter / importer and it represents a population or undescribed species. Because something shows some traits of one l-number and some traits of another is far removed from a hybrid. To be clear, I am talking about a extra-specific hybrid not the hybridisation of two populations. We're also dealing with undescribed or unidentified species in this example so again assuming it's a hybrid is risky.

Calling it L2464 will just get on a lot of peoples nerves as the last thing the l-number system needs is that kind of confusion. L24xL64 would be a better way to represent something that is a hybrid. However, if it were me, I'd just lump it in with

L179

.



Jools

[jackson827]

Wild caught hybrids are very rare to see. If you're saying around 50 a year have been imported for around about a decade then that sounds like the collection of a specific locality, probably by a specific exporter / importer and it represents a population or undescribed species. Because something shows some traits of one l-number and some traits of another is far removed from a hybrid. To be clear, I am talking about a extra-specific hybrid not the hybridisation of two populations. We're also dealing with undescribed or unidentified species in this example so again assuming it's a hybrid is risky.

Calling it L2464 will just get on a lot of peoples nerves as the last thing the l-number system needs is that kind of confusion. L24xL64 would be a better way to represent something that is a hybrid. However, if it were me, I'd just lump it in with

L179

.



Jools

How you can tell the L24XL64 is L179 just based on one picture ever posted online or magazine?
There are many specimen of L24XL64 that show both characters of L24 and L64, some are more like L24, some are more like L64. This phenomenon is more likely to be a hybridization of these two species.

Natural hybridization is rare but not that rare as people thought. People's mind should be open and admit that there are still so many things we don't understand about these pleco creatrures.

[Lycosid]

There are many specimen of L24XL64 that show both characters of L24 and L64, some are more like L24, some are more like L64. This phenomenon is more likely to be a hybridization of these two species.

L-numbers aren't species. L24 is listed as Pseudocanthicus pitanga on the Cat-eLog and L64 is listed as Pseudocanthicus cf. histrix, which means that what species L64 actually is is up in the air. If L64 is P. histrix then any crossing of L64 and L24 would be a hybrid, but the status of L64 seems to be unclear.

Moreover, even species names are (or represent) hypotheses about the relationships between lineages. Freshwater fish are some of the best examples of ways in which the species concept itself can be problematic (see, for example, this article). It is very easy for two varieties of a freshwater fish to exist in different tributaries of a river and meet only in a small zone where these tributaries meet, creating the appearance of two stable species with a hybridization zone when the same species set, found in a lake, would appear to be only two morphs of one species with some intergrades. It can get worse than this, though, since river courses change readily and can promote allopatric speciation in the fish living in these rivers. When the rivers are separate we tend to think of the organisms found in these rivers as separate species. However, they may be reproductively isolated only by geography and not by any biological barrier. If these lineages are allowed to come into contact (either artificially or by another river course change) they will "hybridize", but whether this constitutes what we generally mean by hybridization is up for debate.

As far as what this means for L24xL64 that's perhaps more straightforward. Since fish breeders are often more interested in L-numbers (stable varieties) than in biological species then several of these scenarios collapse into "it's a hybrid of L-numbers", even if biologists wouldn't call it a hybrid. But it's also unclear that even that is what is happening. What if we are dealing with environmentally-determined variation, and the apparent drift between an L24-like and L64-like morphology is nothing more than a sign of variation in the environment where these fish grow up? Perhaps L24 and L64 are simply environmentally-fixed ends of a general Pseudocanthicus variation, and one of these species, or another one entirely, has enough variation left in its environment to produce forms that look like intergrades between L24 and L64?

Basically, there are a lot of possibilities here, and none of the alternative hypotheses have actually been ruled out.

[Shane]

Very well stated Lycosid.

A specific L-number classification does not guarantee a discrete species, multiple L numbers have been given to different populations of the same species. To add to the confusion, sometimes a single L-number may be used for multiple species.

Based on how and why L Numbers are issued it really makes little sense to base a conversation on hybridization using this identification system.

Intra-specific hybridization may very well occur in this genus, but we will need to base that conclusion on scientific species definitions.
-Shane