View Full Version : Ok, whats the deal with the blues?

03-16-2006, 03:54 PM
No scientific classification?
Does ANYONE know what the deal is with that? Is there anyone working on it?
There is an article on this site that touches on the subject...

In speaking with some other respected breeders in the tegu pet trade, some opinions are that the Blue Tegu looks like a form of T.merianae, perhaps from tropical Brazil. There is speculation that perhaps the 'blue tegu' was brought from Brazil to Colombia and exported from there. This would explain why the original shipment came from Colombia, but why not just ship the blue tegu from Brazil? The answer is that Brazil does not allow exporting tupinambis (CITES) so the only way to export these 'blue tegus' were to ship them to Colombia and call them T.teguixin.

Why is there not a lot of interest from the pet trade to look into this or even get involved in this bit of research? Because they would be forced to admit some dealers in Colombia were illegally importing/exporting tegus."

You can read the full article here:

Now Im just wondering, was there only one shipment into this country ever? Have all blue tegus in the united states today originated from this one shipment?
Is there anyone out there obsrving them in the wild? I am intrigued with this mystical, elusive creature.

03-16-2006, 07:12 PM
The answer is basically right there in the link you've provided, but perhaps isn't all that detailed. Years ago, the St.Pierre's got in a shipment from Colombia in which there were a bunch of tegus that to their eyes looked extremely different. They bred these tegus, and then started selling them under the monicker of "blue tegu" and claiming (without any kind of proof at all) that these were possibly a whole new species, or at least a sub-species of Tupinambis teguixin.

I first became aware of this "blue tegu" phenomenon when people saw a bunch of my tegus and were all curious how I had got my hands on so many blues. My tegus were certainly not any new species, they were 100% Tupinambis merianae straight from Brazil (I do research with tegus and we have a breeding colony down there) and so this perked my interest and I started looking into this. I started seeking out anybody that claimed they had a "blue" that they could show me, and everyone of them turned out to just be a particular colour morph of Tupinambis merianae. With my research I've been involved with a number of the scientists who originally described some of the species (Dr. Manzani, Dr. Abe, Dr. Aviles-Perez, Dr. Colli) and when I showed this individuals any pictures of "blues" they ALL emphatically told me that was just T. merianae.

So about 2 years ago I started a rather heated debate upon www.kingsnake.com that started calling into question the St. Pierre's claim of this tegu being either a new species or a subspecies of T.teguixin. In that debate, Stella St. Pierre completely admitted (although not voluntarilly) that they never used the scientifically determined morphometrics or meristics provided to compare their animals, they were " experienced professionals" and "just know". Anyone who's able to read a simple chart and compare the values they see with a "blue" will automatically come to the conclusion that there's no way the "blue" is a subspecies of T.teguixin. In her defence, Stella presented what she calls evidence that the "blue" is not T.merianae, primarily that a cross-breeding attempt failed. Unfortunately, that isn't science, because there's about 20 other reasons why the attempt could have failed and they didn't eliminate those. Her claim was the cross breeding attempt produced embryos that developed but didn't hatch. If something developed to the point of nearly hatching, that actually shows more support for being related than for being non-related.

Anyhow, another argument is they came from Colombia, but that Colombia isn't well known for having T.merianae. This is where the theory that they were smuggled in from elsewhere where animal dealing is more regulated comes from. Maybe they didn't originally come from Colombia, that was just where there departure from South America was.

Several people have argued then why doesn't someone do genetic analysis on these guys to determine the truth. Several problems arise with this. Such a procedure is fairly expensive, and you are not going to find a scientist willing to shell out of his/her own pocket to investigate the species identity of someone's pet. Secondly, with the unconscionable practice of cross-breeding species that is going on, it would likely make any results rather difficult to interpret. You'd first have to go down to South America to collect genetic samples from known populations of specific species for comparison, and then you'd also have to get the St. Pierre's to willingly donate "blue" DNA from supposed pure specimens. Considering how vehemently the St. Pierre's have reacted to having anyone dispute their claim, this might be difficult. Then comes finding the person with the know-how and equipment to actually do the analysis, which will take a fair bit of their time. Essentially, it boils down to spending an enormous amount of money on basically figuring out what someone's pet is.

Until such a step is taken, though, the confusion will likely remain because you get some people who will believe beyond any doubt, without any evidence that they've got a special lizard, and they don't want to be talked out of it. They'll even present what they call evidence of proof, without realizing they aren't presenting any kind of evidence at all, merely stuff they think is evidence (kind of like Intelligent Design - even the Pope acknowledges that the ID Theory isn't based on evidence, only faith). Furthermore, it has already been ingrained into a lot of databases (check out Wikipedia) so to many it is further proof the claim is true. On the other hand, you have people like me who are equally determined to show that the opposite is the case. As our understanding of the various species currently stands, the "blue" should be classified as T.merianae. I'll acknowledge that T.merianae is highly polymorphic and comes in many different morphs, but until someone can actually prove that the various morphs correspond to specific populations that do not interbreed, there's no point in getting into the argument of "new species" or even subspecies.

The various facts on the matter of T.merianae polymorphism that are agreed upon by scientists are:
1) The species appears to adhere to Bergmann's rule - meaning that individuals from populations closer to the pole are larger on average than individuals from populations closer to the equator.
2) Along the longitudinal gradient, populations display different incubation times. Those populations in Argentina have a significantly different incubation time than those populations in say Northern Brazil. This is a phenomenon common with many reptiles that have extended distributions.
3) Populations from wetter habitats appear to more commonly display the dark noses than populations from drier habitats.
4) Populations from more exposed habitats appear to have predominantly darker bodies than populations from more forested habitats.
Combine these points and you'll see that towards more northerly, wetter, forested regions of the South American continent, if there are any T.merianae, they'll likely express a phenotype that most people associate with the "blue" tegu.

03-17-2006, 12:38 AM
I really don't want to get sucked into this old argument that's been gone over and over again both here and on kingsnake.com. But I have to say that there's no more "science" behind your opinion than there is Ron and Stella's. If there was this would have all been settled long ago. It's all just that...opinion. Not that your information isn't valid. But until there's some real work done on the blues they should remain as unclassified.

03-17-2006, 01:59 AM
Ok, you call it my opinion. However, what do you call it when you compare the meristics and morphometrics of known species to what you see in a "blue" and you get a clear elimination of all species but one? What do you call it when experts in the systematic field look at them and say it's a particular species? But you are correct, in that no one wants to look at the data, they want to believe. Faith and fact are completely different subjects, and you cannot logically argue faith. There is indeed a lot more science to my stand than there is Ron & Stella's. In fact, if you go look at their website, they have long since taken down any claim as to the species of this animal because they cannot substantiate their earlier stance.

The blues have the typical colour patterning (don't confuse pattern with colour) of T.merianae (principally the dark, double stripe over the shoulders - T.teguixin has a single stripe). Blues have two loreal scales (T.merianae have 2, T.teguixin have one). Any of the blues I've seen have >130 scales around the midbody (T.merianae usually have 130-178, T.teguixin have 90-125) and >10 femoral pores (T.merianae typically have 12-20, T.teguixin have 5-8). Counting the transverse dorsal rows does have some overlap between the two species, but T.merianae have more than 120, T.teguixin have typically under 120, the blues I've measured are in the 130's. These are facts, not opinion, and back up my claim. I've yet to see a blue "new species believer" present anything to refute these facts and back up the other side of the argument, and I welcome them to do so.

Now, I will admit these morphometric numbers are not carved in stone, the only way that could happen is if absolutely every individual of each species were measured, which is impossible. However, they are very good indicators for what is known. Comparing these facts, even if one doesn't want to acknowledge the exact species, it is absolutely clear that the blues are more closely related to the southern merianae group (T.merianae, T.rufescens, T.duseni) than they are to the northern teguixin group (T.teguixin, T.longilineus and likely T.quadrilineatus & T.palustris). Taking that into account, they are also clearly NOT either T.rufescens or T.duseni and so by simple elimination this leaves us with T.merianae.

However, to reply to your statement that they should remain "unclassified", this makes it a problem, and not a problem to systematic researchers or other scientists, but to actual hobbyists and breeders. As it currently stands, the recognized Tupinambis genus is protected under CITES Appendix II. To make the claim that the blue is unclassified and possibly a new species that scientists are unable to find in the wild could mean these guys in particular get punted up a notch, classified as Appendix I, and lead into a whole lot of legal problems for those people possessing them.

03-17-2006, 02:47 AM
I guess I got my answer, I didn't mean to open up a whole can of worms :oops:

It just seems odd to me that no one has bothered to really research it and give the blues a name. It's only got to be a matter of time, right?

I don't know if I'm opening another can of worms here, but how do you guys feel about the red X blue "hybrids" or whatever they should be called?
Personally, I think it kind of mucks them up, I like nice blue blues and nice red reds. Just my opinion.

And back to the classification thing, who is the "them" that you have to submit the research to to actually have it agreed upon by the scientific community that something is what it is?

And...ok, if the blues are actually a different locality of reds, is there any physical boundaries that would cause them to be an isolated population? if not , then wouldn't there be "in-betweens" floating around??

03-17-2006, 03:27 AM
It just seems odd to me that no one has bothered to really research it and give the blues a name. It's only got to be a matter of time, right?

Actually, I think it's more a matter of money, and a considerable amount. Something like this is an expensive experiment, and until it's done, believers won't accept anything less. So unless someone is willing to fund the endeavor, it'll likely remain unsolved.

I agree with you on the hybrids, I personally find them to be basically an abomination. Don't get me wrong, they can be pretty and all that, but it begs to ask a question: Are 'hybrid seekers' really interested in the animal or are they interested in a status symbol? Not to overlook the fact that hybridizing posses many potentials for ecological catastrophies. I think if people are going to be hybridizing, then regulations need to be established wherein each animal can be guaranteed specific identity, registered, and if the whereabouts of said animal cannot be 100% verified as secured, then the last registered owner is severely fined.

And back to the classification thing, who is the "them" that you have to submit the research to to actually have it agreed upon by the scientific community that something is what it is?
You do your research, analyse your data, write a manuscript and submit it to the appropriate research journal. The journal then sends your manuscript out to the leading authorities in the field and they judge whether it is worthwhile for publication or not. Once published, it is usually excepted as valid data. However, there are some loopholes and some journals are not as strict as others. Take for specific interest the tegu Tupinambis quadrilineatus. As I understand the situation, this species was first discovered well before the actual papers were published by my friends Augusto Abe and Dr. Colli during a wildlife rescue (the Brazilian gov't had built a huge hydro dam, and conservation officers went in and rounded up the wildlife before flooding was commenced). They both sat on the data for about 10 years, and then each on their own decided to publish their data with the help of some new associates. Augusto published his paper in a lesser known journal in Brazil calling the species T.quadrilineatus in 1997. Colli and others published their's in Herpetologica (a more widely known journal, calling the species T.cerradensis) the following year, as the referees for that manuscript were unaware of the earlier paper. Nevertheless, under ideal circumstances, such papers are scrutinized by acknowledged experts in the field before they are published. You would further (in the case of identifying new species) have to present the holotype (preserved specimen of the first acknowledged individual of the species) along with it's EXACT credentials - ie. exactly when and where the individual was captured. Something that basically cannot be done for "blues".

As for if there are any populations of blues, or zones of hybridizing reds and blues in the wild, um, that's kind of a faulty question. First, scientists have yet to acknowledge blues. What they find in the wild they claim are T.merianae. There could quite possibly be a natural zone of hybridization between T.rufescens and T.merianae, but no one has found any such occurance. Personally, I'd also say no one has looked close enough. What is acknowledged at T.merianae is highly polymorphic - it has variable sizes and colours depending on the locality. It is quite possible that T.merianae actually encompass several species, but then again, you get into the debate over just what exactly a species is, and that I guarantee you isn't a can of worms to open. South America is actually very poorly inventoried fauna- and flora-wise, so there could actually still be other completely different species to be discovered - take the above example, it was only discovered after basically their habitat was destroyed.
But back to your main point about "in betweens" floating about, it is possible, but often turns out to be not likely. Very few species hybridize naturally. But on the otherhand, there are those animals that at one time were thought to be different species (often because of colouration - something scientists seldom rely on anymore) but were later found to have a zone of "hybridization" between the two forms, and so it was later decided to consider the two species to actually be one.

03-17-2006, 02:39 PM
It has been proven scientifically without a doubt that the Blue Tegu is not T.teguixin

The Blue Tegu does not even appear to be from the same clade as the T.teguixin, according to the scientific data we have (as exampled by the image in the first post of this thread).

The Blue Tegu is more likely to be the same clade as the Argentine Black & White, Argentine Red, T.duseni (Yellow Tegu), etc.

The Blue Tegu has not been proven to be any exisiting species or subspecies, nor has it been proven to be a new species or subspecies.

So, at this point my opinion is..

The Blue Tegu is "Undescribed" or "Unclassified". This does not mean it's a new species, just that it has not been applied to any one group yet.

In defense of Ron & Stella, they labelled the blue tegu what they assumed it was. They did state in a public forum that they just based their opinion on where the shipment originated from. They did also agree that if any qualified professional contacted them, they would help out to determine what species the blue tegu is. I assume they would give a scientist a genetic sample if requested.


03-17-2006, 08:38 PM
Can I just throw my 2 cents in?

Ron and Stella are really nice people. They are not scientists, they are not researchers. They are people just like us who love tegus. In addition, they are very helpful when it comes to questions about tegu husbandry.

Currently, the only fact that I believe, is that a shipment of tegus (teguixin) came in from Columbia. Some looked different. Ron liked them so he took them, just like any of us would have done. As they grew up they had blue coloration. So the name 'blue tegu' seemed appropriate, makes sense to me.

The blue tegu may not be classified during some of our life times. In retrospect, T.merianae wasn't classified until recently. Not to long ago the Argentine Black and White was called T. teguixin.

My opinion is that all tegus are amazing. So which ever kind you have just love it and take care of it. The rest will fall into place.

01-11-2009, 02:09 AM
This is very interesting, so much time, thought and effort involved. tupinambis has so much knowledge on this... amazing