`Does it not demonstrate that Elaphe is paraphyletic?'



As mentioned, it doesn't accurately depict the situation. See the attached .jpg, figure 4 from the Utiger et al. paper. I put a line down along the taxa that were included in Elaphe prior to this paper. Rhinechis and Oocatochus, as mentioned elsewhere, were split from Elaphe by Helfenberger. Coelognathus, the other genus split by Helfenberger, doesn't appear here. All taxa included are more closely related to each other than they are to Ptyas, and Euprepriophis forms the outgroup (though poorly supported) to the remaining taxa. No well-supported relationships exist between the groups within Elaphe sensu lato that Utiger et al. split into seperate genera and, consequently, neither monophyly nor paraphyly are supported for Elaphe sensu lato.



`Did you really read the paper? If so, you should see that an intolerance of paraphyly is the reason they split Elaphe. I cannot find a single paraphyletic taxon in their strict consensus tree except perhaps Pantherophis. It does look like they have left Pantherophis paraphyletic.'



First, that an author has not created paraphyletic taxa does not imply that the author is intolerant of paraphyletic taxa. In this case, there simply are no well-supported paraphyletic taxa that could have been created within Elaphe, and the authors clearly voice their support for the existence of paraphyletic taxa.

Second, if they had left Pantherophis paraphyletic this also would have proven that the authors were not committed to the avoidance of paraphyletic taxa. However, their results did not show Pantherophis to be paraphyletic (on p. 113-`Pantherophis and Pituophis are sister taxa (bootstrap support 92%, Figs. 3-4) and the monophyly of the former is well supported by a bootstrap value of 74% (see footnote 6).'--footnote 6 referring to new calculations done after submission that include Rhinechis which slightly change the bootstrap percentages). One of several phylogenies they constructed suggested that this was the case, but this phylogeny was rejected by the authors, and was not published. LInked below for clarity are the sentences in which Utiger et al. address the issue.



`The authors do not provide a key for distinguishing the many genera they recognize.'



I don't believe this is necessary for the taxa to be morphologically distinguishable.



`The only diagnoses they provide are the two new genera they propose.'



And diagnoses for the other genera already exist.



`In the diagnosis of Orthriophis, they state: "subocular usually present (often absent in hodgsonii, sometimes also in cantoris and taeniurus)..." That sort of definition for a new genus does not inspire confidence since one of the diagnostic characters for the genus is variable within the genus.'



OTOH, other characters are given that adequately allow the genera to be distinguished.



` If you disagree, then perhaps you can tell us how one can distinguish,say, Zamensis from Orthriophis and Elaphe from Coronella. I simply can't find anything that would allow me to do that in this paper.'



I don't happen to have copies of the papers in which Elaphe, Coronella, and Zamensis are described, so I can't give you the various characters involved for them. I suggest you consult those sources.



If your wish were simply to be able to identify them, this would be quite simple given any familiarity with the taxa involved based simply on color patterning and the like.



` In sum, even the authors themselves disagree on the acceptability of paraphyletic taxa, but apparently the cladists among the authors win. They do throw a bone of concession to the Darwinians by recognizing a single paraphyletic genus: Pantherophis. But I am afraid that this bone is tied to a rope and that it can be withdrawn any time.'



This appears to be simply speculation on your part, and the paraphyly of Pantherophis is not supported by the authors.



`Who is going to stop someone else from splintering the paraphyletic Pantherophis in the future?'



Any taxonomist who cared to present compelling reasons for rejoining them, supposing data demonstrating the paraphyly of Pantherophis were presented and the split made, would be free to do so.



`Paraphyletic taxa are indeed the inevitable result of the process of evolution. There is therefore no scientifically tenable reason for not recognizing paraphyletic taxa such as Elaphe.'



It is far from certain that Elaphe sensu lato is paraphyletic (the evidence I'm aware of appears to argue strongly against it), and, of course, even if one accepts paraphyletic taxa in principle, it doesn't follow that all paraphyletic taxa should be recognized or that scientifically tenable reasons for rejecting certain paraphyletic taxa don't exist.



Patrick Alexander

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