Hybrid Ambystoma mexicanum x Ambystoma andersoni

[Bellabelloo]

I would like to start this post by stressing that I personally would not have let the breeding occur. The breeder of these wished to check the fertility of a male Ambystoma andersoni before acquiring some females. He kindly sent me approximately 10 eggs to raise as I was curious to see how they would develop. He will add further details shortly.
I would also ask that anyone else who considers doing this to think of what you aim to do in the long term. These animals will never leave my care, these could live with me for the next 15 years. I feel it would be irresponsible to raise them and sell/re-home any offspring to anyone.

The eggs where laid early June and kept in cool water , the first hatched on the 21/6/12 and I saw that it fed right way on some small pond invertebrates. Subsequent larvae did the same and where offered microworm and small daphnia . As they grew larger they where fed on live bloodworm, whiteworm and any other aquatic insects that I could find. They spent the summer months in a tub outdoors. They will spend the winter months in my shed.
I have raised Ambystoma mexicanum before, and I was expecting to see cannibalism, or missing body parts. I was hoping that this would reduce the numbers, but they did not co-operate and I did not loose any larvae. Some where culled as I did not wish to raise 10 to adult hood. To date, despite living in the same tub, I have never seen any missing body parts. They seem very docile compared to Ambystoma mexicanum.
Hopefully they will reach adulthood and I may see if I can raise another generation. This however depends on if I still have space for another group.

 

[axolotlfreak56]

They're hybrids but its still a very beautiful animal.

 

[millerj76]

I would like to start this post by stressing that I personally would not have let the breeding occur. The breeder of these wished to check the fertility of a male Ambystoma andersoni before acquiring some females. He kindly sent me approximately 10 eggs to raise as I was curious to see how they would develop. He will add further details shortly.
I would also ask that anyone else who considers doing this to think of what you aim to do in the long term. These animals will never leave my care, these could live with me for the next 15 years. I feel it would be irresponsible to raise them and sell/re-home any offspring to anyone.

The eggs where laid early June and kept in cool water , the first hatched on the 21/6/12 and I saw that it fed right way on some small pond invertebrates. Subsequent larvae did the same and where offered microworm and small daphnia . As they grew larger they where fed on live bloodworm, whiteworm and any other aquatic insects that I could find. They spent the summer months in a tub outdoors. They will spend the winter months in my shed.
I have raised Ambystoma mexicanum before, and I was expecting to see cannibalism, or missing body parts. I was hoping that this would reduce the numbers, but they did not co-operate and I did not loose any larvae. Some where culled as I did not wish to raise 10 to adult hood. To date, despite living in the same tub, I have never seen any missing body parts. They seem very docile compared to Ambystoma mexicanum.
Hopefully they will reach adulthood and I may see if I can raise another generation. This however depends on if I still have space for another group.

Firstly, they all look in great condition, great job. Theres people who will and people who won't when it comes to hybrids. Not sure how many hybrids are in the amphibian/reptile world but for sure the fish world has plenty. Axolotls are used in laborotories and experimented on, so testing an Andersons fertility with an axolotl don't seem so bad, and the fact you have been responsible, culling and raising only a few with intentions of raising and keeping. Your hybrids are very nice, all seem to have good proportions.

 

[xxianxx]

I was the breeder, as Julia stated , hybridization is not recommended and his highly frowned upon by many people. These hybrids were never ment for sale nor are they for general release into the hobby. I sent out two batches of eggs to people who could be trusted not to pass them off as A.andersoni or try to capitalize on their potential value . The only reason I did this was that I had a lone male A.andersoni and had arranged a breeding lone with a UK owner of a couple of females. Rather than go to the trouble of collecting, quarantining and then attempting to breed them only to find I had a dud male, I decided to place a female wild type A.mexicanum in the tank to check. They bred within a couple of weeks. All my larvae tanks at the time were maxed out by a full batch of A.mexicanum eggs and a couple of other species, so upon hatching they were placed in holding tanks and used as feeders for my adult P.waltl. They were kept in my shed whilst the A.mexicanum were kept in my house to avoid any confusion over which was which. Other than Julias and the ones in my possession all of the hybrids are dead. Julias eggs hatched without problem whilst the other batch failed, I isolated ten hybrids at random and placed them in a daphnia tub outside, with full intention of giving them to owner of the failed eggs. Unfortunately he is ill and I have been unable to get in touch with him, so I have decided to keep them myself, though I will be selecting three to keep and the rest will be culled at adulthood once I can determine their sex though I may be open to offers by research facilities for them with the proceeds being donated to this site. Of the original ten I found seven left in the daphnia tub, there was some dragon fly larvae in there so that is the probable reason for the missing larvae. At the moment they range in size from 3.5"-5", they could very easily be mistaken for wild type mexicanum though they do display an unusual mottled flank and with a redish/pink colouration with a greenish tinge, the gills are also prone to curling forward in the A.andersoni fashion, the most striking difference however is in their behavior, which Julia has also observed, they are very unaggressive in comparison to A.mexicanum , not a single missing limb and the only damaged tail amongst them is due to a syphoning accident. I look forward to seeing how these guys develop and wether they show a propensity to morph and they will be used for providing feeders in the future.

 

[esn]

Very interesting little guys. I'm glad they're in good hands because those, especially the ones in Ian's first picture, look like they could be easily passed off as Andersoni. I have also noticed with my own pair that they do not show the same aggression as axolotls seem to - I have never seen them snap at each other as I have noticed on frequent occasions with Mexicanum. I wonder if this may be because they have better eyesight and awareness? Who knows.

Update with some pictures when they reach adulthood. I want to see how they turn out in the end.

 

[xxianxx]

Very interesting little guys. I'm glad they're in good hands because those, especially the ones in Ian's first picture, look like they could be easily passed off as Andersoni.

Thats the reason I turned down a big pile of cash for the full batch, they could potentially have been passed off as andersoni and contaminated the UK population . I have no doubts that this will happen in the near future but did not want to be responsible for it myself.

 

[Neil C]

I'm just curious as to why they would be so valuable? Would it be that hard for some else just to buy one of each and then breed them? Is it because the eggs are usually sterile?

They certainly look like axolotls from above but it's another story from the side. Very beautiful and I do like the gills curled forward look.

Regards Neil

 

[xxianxx]

I'm just curious as to why they would be so valuable? Would it be that hard for some else just to buy one of each and then breed them? Is it because the eggs are usually sterile?

They certainly look like axolotls from above but it's another story from the side. Very beautiful and I do like the gills curled forward look.

Regards Neil

A.andersoni are hard to get and expensive in the UK, my first pair cost £140 at 2" and I thought that was a bargain. If the hybrids look like them they could potentially be passed off as them. Miss selling of A.andersoni in the UK has been reprted once on this site allready. From what I have read the eggs are usually fertile.

 

[jasper408]

A.andersoni are hard to get and expensive in the UK, my first pair cost £140 at 2" and I thought that was a bargain. If the hybrids look like them they could potentially be passed off as them. Miss selling of A.andersoni in the UK has been reprted once on this site allready. From what I have read the eggs are usually fertile.

What a sad state of affairs. Do you happen to know of the hybrids can produce viable offspring?

 

[Bellabelloo]

I see no reason why they shouldn't...time will tell I think.

 

[jasper408]

Mules are effectively sterile and are the result of hybridization. I hope that's the case for the sake of species.

 

[MarioR]

All known ambystomatid hybrids are fertile

Greetings,
Mario

 

[michael]

I think hybrid A. mexicanum A. andersoni could possibly be an important research tool. If they could be certified as non CITES animals. That way they could be shipped from country to country without the long wait for CITES pemits. Researchers could avoid bottle necks in obtaining animals. It really muddies the water for the hybrids to be in hobbyists hands. Some breeders are trying to brand every oddball axolotl they breed with their own special name. These "new morphs" of axolotls are offered at obscenely high prices much like oddball snakes and lizards are.

It sounds a little elitist for a hobbyist to say it is o.k. for me to have the hybrids but is not o.k. for hobbyists in general to have them. I do understand your thinking but it is a fine line.

 

[joeyasaurusrex]

hi, sorry to disagree, but I tend to agree with the idea not to mess with the purity of the andersoni... and while I feel like it's still pretty easy to find pure mexicanum, I would totally feel duped if I bought an andersoni and it wasn't actually one at all, especially if I had in mind to breed them.

I myself toyed with the idea of breeding ambystoma tigrinum with mexicanum, but was promptly corrected by fellow caudata members.:happy: Their points are valid.

Not to mention, I myself am not to impressed with the color pattern of these particular hybrids... much prettier as pure andersoni.

 

[Azhael]

I can only say that if these little fellas are to exist, i´m SO glad they are in your responsible hands, Julia.

 

[esn]

It sounds a little elitist for a hobbyist to say it is o.k. for me to have the hybrids but is not o.k. for hobbyists in general to have them. I do understand your thinking but it is a fine line.

I don't think it's elitist! You're an experienced keeper. I think of this in the same way as I think of venomous snakes. Most people keeping them are hobbyists, but there are certain hobbyists with decades of experience that really should be the only ones to have them. With something that can so easily bite back (literally for snakes, metaphorically for hybrids), I think it has to be only certain hobbyists that are allowed this sort of thing.

It sounds totally hypocritical, I know! But I understand what you're trying to say. There are hobbyists and scientists, but then there are experienced hobbyists that can be trusted to make wise decisions - such as culling most the batch in Ian's case. If a twenty year old told me he just got a copperhead to be his best snakey friend, I'd be incredibly worried. If it was a guy who I know has been working in the hobby for quite some time and is responsible, I'd leave him be (unless he didn't have the license for hots, hah).

I think it would be interesting, and I've been considering trying to get my college to let me do a study on andersoni x mexicanum. But that's a bit hard considering they're near unobtainable in the U.S. and I only have one pair of andersoni. My professors are very interested in it, but we've agreed that we ought to stick to mexicanum because the andersonis are so hard to obtain! Still some great things to learn. I wonder if Ian couldn't find a college in the UK interested in studying them if he can fertilize any more? It'd be interesting to see if there was any difference in regrowth abilities between mexicanum, andersoni, and the hybrid. That would be a start. And another would be behavioral studies.

hi, sorry to disagree, but I tend to agree with the idea not to mess with the purity of the andersoni... and while I feel like it's still pretty easy to find pure mexicanum, I would totally feel duped if I bought an andersoni and it wasn't actually one at all, especially if I had in mind to breed them.

I myself toyed with the idea of breeding ambystoma tigrinum with mexicanum, but was promptly corrected by fellow caudata members.:happy: Their points are valid.

Not to mention, I myself am not to impressed with the color pattern of these particular hybrids... much prettier as pure andersoni.

This sounds like it might have been a misunderstanding? I'm not sure. Ian culled most the batch and only gave a few to two trusted people who would not allow them to enter the trade. I don't see a problem with it if they're not entering the trade. It isn't fouling the purity of the andersoni if they aren't bred with the general population, though that has been happening in other countries for sure! Some in the US are being sold as axolotls by people who know nothing and are just breeding them.

----


I think it's also important to note that andersoni and mexicanum most likely came from the tiger salamander originally, which makes them very similar. They developed much the same way in separate lakes, essentially becoming mirror species in isolation. Animals are known to hybridize naturally in the wild, especially with changes in the environment. Human encroachment on territory normally only serves to speed up this hybridization, so I can't say that it is truly unnatural in essence, only in the speed at which it happens or the methods for its achievement. Who is to say that these species would not have hybridized in the wild with another species (tiger salamanders) had things turned out differently, or had their endangerment escalated at a slower pace?

The fact that they can hybridize means that there is a reason they can do so, and I think it's something that should be researched, albeit responsibly. I'm saying this because this is a topic that has come up multiple times, where people have questioned the ethics of hybridization. Under the right circumstances, I believe it is ok. From a scientific standpoint, paraphrased from my professors:

1) If there is a legitimate reason for doing so (some merit to it)
2) If the population is controlled and not let loose
3) It is responsibly done and kept track of

Then there shouldn't be an issue. I doubt the andersoni that boinked that axolotl questioned the ethics of it.

 

[methodik]

h and while I feel like it's still pretty easy to find pure mexicanum

Could anyone validate on this statement?

 

[esn]

Could anyone validate on this statement?

Hasn't it been pretty much concluded that axolotl color morphs are due to hybridization? At least, the ones that we purposefully breed for in albino and golden albino. That's what I've read, outside and on this forum.

 

[Dr0gr1n]

I had commented in a thread awhile back about potentially doing the same type of cross and was torn to threads for thinking about it. I see no problem with it given the animals are not sold as andersoni nor as mexicanum. They should be kept separate from your other stock and clearly labeled on their tanks.

As long as people are ethical when making these crosses and not for a quick profit that has the potential to ruin the gene pool of the andersoni wich are few and far between here in the US, not to mention add potential unwanted traits to the mexicanum gene pool, such as being prone to morphing, higher sensitivity to water temp and quality.

On the other hand there could be some good traits that could be passed on such as unique colors, the easier temperament leading to less or no cannibalisation of siblings. Others may be pressent but until more research is done we will never know.

I am all for keeping strains as pure as they can be but let's face it, this is a cool and interesting concept to many hobbiests.

There is room for both to occur.

 

[Kaysie]

The problem with letting both occur concurrently in the hobby is that you have that one asshat who passes off hybrid animals as pure to unsuspecting Suzie Axiekeeper, who then breeds it with the one at home, and then sells off the babies to more unsuspecting Happy Bunny Club members.

Granted, most serious keepers know better than to get stock from people like Suzie, but that's how things 'accidentally' leak. It just takes one person with a little less morals than people like Julia, Ian, and Michael, and the whole species gene pool is in trouble.

Some people can't be trusted to be ethical or honest. Some people just have no ethics at all.