>>Just got Utiger et al.'s paper (Russian Journal of Herpetology, Vol. 9, no. 2, pp. 105-124) from the library. Looking at page 115, their fig. 4, strict consensus tree. I find no evidence that the ratsnakes are polyphyletic. All of the species they studied form an unresolved polytomy, with the exception of the North American species of ratsnakes, kingsnakes, gopher snakes and glossy snakes.



Correction: a number of species groups are highly supported. The relationships *between* these species groups are unsupported and unresolved.



> This node has low bootstrap value; it is poorly supported. Therefore it appears that all of the species they studied are simply part of an unresolved polytomy.



Correction: the often highly supported *species groups* emanate from a largely unresolved polytomy.



> In other words, their analysis largely failed to tell us anything about the branching order of the many genera they recognize. To splinter Elaphe on the basis of such a poorly resolved phylogeny is simply scientifically untenable. Arnold Kluge, when he was faced with a similarly unresolved polytomy in his erycine paper, dumped all of the species in the polytomy into the same genus, Eryx. I criticized him for doing that and said that he should have maintained the taxonomic status quo. Utiger et al., too, should have maintained the status quo. Instead, they named 2 new genera and resurrected a number of old ones, thus creating taxonomic chaos by the truckload.



Taxonomic chaos by the truckload? Hardly. History suggests that after a few years of readjustment, these changes get absorbed fairly easily. Who, today, still uses Bothrops schlegelii or Bothrops nasutus instead of Bothriechis schlegelii and Porthidium nasutum?



> All of the name changes they propose, including the proposed transfer of the North American species of Elaphe into Pantherophis and Pseudelaphe, are unnecessary, destructive and scientifically untenable.



Correction: the node supporting the monophyly of Pituophis and Pantherophis is strongly supported. If you don't like Pantherophis, you can always consider Pantherophis Fitzinger, 1843 as a junior synonym of Pituophis Holbrook, 1842. Welcome Pituophis guttatus, obsoletus, bairdi and vulpinus! But then again, Lirpa 1, Cal King, RS Newton, or whoever you are, you seem to be the born again anti-cladist, so nothing will ever convince you that classification should follow phylogeny.



Cheers,



Wolfgang
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