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My fingers are raw from googling, and I can't get a definitive answer. What does the ICZN currently recognize for North American rat snakes? _Pantherophis_ or _Elaphe_? I know there's plenty of debate, but I need to know which one is official right now.

Thanks!

99% sure its elaphe. I assume you mean a 'black rat snake' or a 'chicken snake' as is common in the southeast usa where I live. I do think its elaphe, though. It always used to irritate me when I'd see cornsnakes such as okeetee corns, elaphe guttata, being put into the same exaxt category as ratsnakes such as the elaphes. I might be totally wrong tho.

Why and who thought it should be changed Pantherophis (what does it mean?) V

>>Why and who thought it should be changed Pantherophis (what does it mean?) V

A few years ago, Utiger et al. published a paper using a curious mix of taxonomic characters. They used mtDNA and hemipenis morphology to come up with a tree. Then they base their taxonomic proposal on that particular tree and carved it up so that only holophyletic groups (groups that consist of a single common ancestor and all of its descendants) are recognized. Since the recognition of such genera as Lampropeltis, Pituophis and Arizona renders Elaphe paraphyletic (i.e. does not include all of the descendants of a common ancestor), they then split up Elaphe into about a dozen genera, without ever defining these genera morphologically nor did they inform us how these genera differ from one another. The generic name for most North American species is Pantherophis, according to Utiger et al.'s proposal. Since many practicing taxonomists belong to the school of cladistics and since they share Utiger et al.'s intolerance of paraphyletic taxa, they immediately embraced the new proposal. Other, less knowledgeable people, also embraced the new proposal because they automatically assumed that the newest names must be the most correct. Since the name Pantherophis was published in one of those lists of "current scientific names", even more uninitiated people who have never read Utiger et al.'s proposal immediately assumed that Pantherophis must be the correct name.

The fact of the matter is that there is no official list of scientific names, because science is not a popularity contest, and there is no committee that decides whether one theory or another is proven. The ICZN is also not in the business of arbitrating which taxonomic proposals are correct or incorrect. Therefore the ICZN is not in any position to rule whether Pantherophis is the correct name for the North American ratsnakes like the corn snake, black ratsnake, fox snake, or Texas ratsnake.

Well, the answer to your question is "both".

The ICZN is simply a set of rules governing the correct publication of names and various related matters. It does not decide between alternative classifications. Both "Elaphe" and "Pantherophis" and, for particular species, "Elaphe guttata" and "Pantherophis guttatus", "Elaphe obsoleta" and "Pantherophis obsoletus", etc., have, from the point of view of the rules of the ICZN, precisely equal validity.

If you want to know if you should call a corn snake "Pantherophis guttatus" or "Elaphe guttata", that's a question the ICZN does not answer. You have two basic choices in answering it: 1) "go with the flow" and use whichever name is typically used by the people you associate with or is advocated by a particular herpetological society; 2) read the publications and make up your own mind. Following option "2", my own opinion is that "Pantherophis" is the correct genus for the various U.S. critters recently placed in Elaphe (except Senticolis triaspis, Bogertophis subocularis, and Bogertophis rosaliae). This opinion seems to be shared by most professional herpetologists as well, although I'm not sure how widespread it is in the hobbyist community.

>>The ICZN is simply a set of rules governing the correct publication of names and various related matters. It does not decide between alternative classifications.

Yes I agree with this, since the ICZN is not setup to decide whether any single taxonomic proposal has scientific merit or not.

>>If you want to know if you should call a corn snake "Pantherophis guttatus" or "Elaphe guttata", that's a question the ICZN does not answer. You have two basic choices in answering it: 1) "go with the flow" and use whichever name is typically used by the people you associate with or is advocated by a particular herpetological society; 2) read the publications and make up your own mind.

I also agree with this.

>>Following option "2", my own opinion is that "Pantherophis" is the correct genus for the various U.S. critters recently placed in Elaphe (except Senticolis triaspis, Bogertophis subocularis, and Bogertophis rosaliae). This opinion seems to be shared by most professional herpetologists as well, although I'm not sure how widespread it is in the hobbyist community.

Since you apparently claimed to have read this paper, it is unfortunate that you did not tell us why Utiger et al. is correct in resurrecting Pantherophis. As to whether other herpetologists think it is a valid proposal, that becomes option "1". Personally I oppose the proposal because Utiger et al. did not even attempt to define each genus morphologically. If someone were to find a new species of ratsnake somewhere in China, or perhaps the Balkans, there is no way to figure out which of Utigers dozen or so genera this new species rightfully belong. A new phylogenetic analysis would need to be performed. Depending on the results of the new analysis, there can be wholesale changes to Utiger's taxonomy. We may need to disqualify some of their genera, rearrange the others and name new genera. Taxonomy based on a religious intolerance of paraphyletic taxa is not the best way to classify organisms.