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If someone could answer my questions I would appreciate it. If there is a difference between a Brazilian Rainbow and Peruvian Rainbow I understand it to be a difference in scale count, coloration, and possibly size. Where is mid-body exactly? Does that mean yor unroll a shed and fold it in half and count it there or at the snake's widest girth or what? How is a sub-species actually classified? Does that mean it it reproduceable with a phenotype or genotype or both?

I don't know my biology too well, would a Peruvian have different ancestrial lineage than a Brazilian?

I am just curious, my male has scales twice as big as my female, is larger, and overall looks very different. At 2 1/2 feet from head he has a scale count of 43, was sold as a Brazilian, and is a larger snake. I see so many comments about Peruvians that it makes me think that he would be classiefied as one, but I just don't see how there would be any evidence or real reason to know.

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"There is a principle which is a bar against all information, which is proof against all arguments and which cannot fail to keep a man in everlasting ignorance- that principle is contempt prior to investigation." Herbert Spencer

Sunshine,
. As you know there is considerable disagreement about this subject. The Epicrates cenchria gaigei subspecies was described and the type specimen cataloged 60 years ago. Nothing with any recognized taxonomic weight has been done about =this subject since then. It is not likely that anyone will come along soon with the scientific scholarly taxonomic authority to settle this issue. BTW, back in the sixties we were having the same sort of discussion about the subspecies of Boa Constrictors. I get a laugh seeing some of those same arguements ongoing on the Boa Constrictor forum today.
. What is a species and what is a subspecies? It used to be that the accepted definition of species was that if two animals could breed and produce viable fertile offspring they were the same species. What we have seen in all sorts of captive breeding programs is that this deifinition is not valid. The science of taxonomy is constantly changing. Many taxonomists argue that subspecific differentiation is not valid. Many people who know Rainbow Boas make the arguement that Brazilian and Peruvian Rainbows are too similar to be different subspecies. Among those of us who have Peruvian Rainbows and that do in fact have snakes with very different scale counts we argue that the snakes are different and so they should be classified as different subspecies. Admittedly the difference between a Yellow Ratsnake and a Black Ratsnake which are subspecifics seems greater than the difference between E.c. cenchria and E.c. gaigei. However these two snakes though very different looking because of different color and pattern have other very similar morphological features including virtually the same scale counts. To me it seems that scale counts are and should be more definitive than color or pattern variations in differentiating subspecific status. I have seen so much variation in color and pattern of Brazilian Rainbow Boas including all the chacteristics that many ascribe to Peruvian Rainbows that I do not think color or pattern variations are valid in identifying these two subspecies.
. Can Peruvian Rainbows be successfully bred to Brazilian Rainbows? Yes, of course they can. Going back to that old definition the answer would be yes and we now even know of many many successful cross specific and even cross generic breedings in reptiles AND other animals. I do not know for sure but I think it highly likely that people have been unknowingly crossing these two subspecies for some time.
. Midbody scale counts? When I make scale counts I start out with a count at what seems to be around the midbody point. I then try counting some forward and aft of both of these spots and in the end use the highest number from all of these counts. There are a few snakes which will have the highest count forward or aft of the mid point but with Rainbows midbody or close to it nearly always gets the highest numbers.
. Different ancestrial lineage? Yes, I think so but I do not expect anytime soon for someone to completely explore and describe the genomes for all of the snakes we are interested in to prove or disprove this.
. When I saw PICs of your male I noticed that he had very large scales. Where did you get him? When I was building my collection my wc adults mostly came from the very northern most part of the BRB range. Most of the CB BRBs in my collection probably came from bloodlines from the same area. Perhaps because of this my BRB scale counts are very consistent and high. Those people who have done field work in central and northern Peru report more variation and generally lower scale counts for animals from that part of the BRB range. Some of them think this is part of the range of gigei but I think they are wrong. This scale count variation would indicate that there is a clinal difference in scale counts rather than a geographic line of demarcation with very different scale counts on either side of the line of demarcation.
. I welcome those who disagree to state their side in this arguement. I have made at least some effort to state their case in this post. I can agree to disagree with them. I count many of them among my friends. And......I have come to realize that many questions do not have exact answers.
Jeff

>>If someone could answer my questions I would appreciate it. If there is a difference between a Brazilian Rainbow and Peruvian Rainbow I understand it to be a difference in scale count, coloration, and possibly size. Where is mid-body exactly? Does that mean yor unroll a shed and fold it in half and count it there or at the snake's widest girth or what? How is a sub-species actually classified? Does that mean it it reproduceable with a phenotype or genotype or both?
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>>I don't know my biology too well, would a Peruvian have different ancestrial lineage than a Brazilian?
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>>I am just curious, my male has scales twice as big as my female, is larger, and overall looks very different. At 2 1/2 feet from head he has a scale count of 43, was sold as a Brazilian, and is a larger snake. I see so many comments about Peruvians that it makes me think that he would be classiefied as one, but I just don't see how there would be any evidence or real reason to know.
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>>"There is a principle which is a bar against all information, which is proof against all arguments and which cannot fail to keep a man in everlasting ignorance- that principle is contempt prior to investigation." Herbert Spencer

" Scale counts are and should be more definitive than color or pattern variations in differentiating subspecific status" I read everyday, the Boa, tortoise and Rainbow boas forum and I have seen breeder in the boa forum saying that they do not believe in scale counts to indentified species or sub species, at least Liannaus is dead and does not has to heard this kind of thing

I pretty much agree with what Jeff is saying and I share many of his observations.
I will admit that I am a skeptic though as regards to many of the so called "Peruvian" rainbows that are around now in the US. Way too many importers/dealers/breeders are calling their animals 'gaigei' simply because they came from Peru, as if the subspecies somehow recognize man-made borders. I think it is clear that if gaigei does exist (as it probably does) it comes from SOUTHERN PERU and Bolivia.
One other caution though.....regardless of what a rainbow's scale count or appearance is, without known locality data it CANNOT (!!!) be stated that it is a "true gaigei". There has been too much interbreeding with captive populations to make such a definitive statement as many dealers do. You must know where it, or it's parents came from. You can't assume.

Thank you for your comments. It will be interesting to see what develops, if anything, from these discussions.
Linda