`You are quite correct that whether or not Pantherophis is recognized, Elaphe is paraphyletic. However, there are some systematists who claim that Elaphe is polyphyletic. One would hope that practicing systematists should be able to distinguish between polyphyletic and paraphyletic but that is sadly not the case. More than once I have heard them explicitly claim that Elaphe is polyphyletic.'



And, even worse, some people forget which word they ought to use in online discussions. Utiger et al. demonstrate that Elaphe is polyphyletic. Sorry about the mistake.



`That depends on how one defines "lampropeltinines." Long ago it was demonstrated that New World Elaphe and genera such as Lampropeltis, Pituophis and Arizona share the synapomorphy of an interpulmonary bronchus. This character is not present in Old World Elaphe. This fact has prompted some systematists to propose classifying New World Elaphe in a different genus than Old World Elaphe but no formal proposal has been made to effect such a change.'



I disagree. The change was made by Utiger et al.



`Senticolis does not have the interpulmonary bronchus. Hence it is not a member of the Lampropeltini.'



Though the point was not addressed by Utiger et al, it is addressed by Rodriguez-Robles (`Molecular Systematics of New World lampropeltinine snakes (Colubridae): implications for biogeography and evolution of food habits' Biological Journal of the Linnean Society, v. 68)--Senticolis is a lampropeltinine if Lampropeltini is defined based on phylogeny rather than morphology.



`I am not surprised that a study concludes that Old World Elaphe is not basal to Lampropeltini and Senticolis since Senticolis is one of those taxa that is more like a racer than a ratsnake.'



The inclusion of Senticolis is not responsible for the derived status of Pantherophis (was Elaphe) within the lampropeltinines. Arizona, Bogertophis, Lampropeltis, and Pseudelaphe (was Elaphe) were also all basal compared to Pantherophis in the Utiger et al.'s phylogeny.



`That is why I support Dowling's decision to remove it from Elaphe and place it in a genus of its own some years ago. Senticolis, being closer to the racers, is probably basal to Old World Elaphe and New World Elaphe.'



As it would happen, according to Utiger et al.'s phylogeny Senticolis is not basal to Elaphe sensu lato, though it is basal to the rest of the Lampropeltinines.



No offense, but you really should read Utiger et al's paper before you decide that you disagree with them.



Patrick Alexander

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