Just found Dessauer et al. (1987, Fieldiana Zoology), which is supposedly one of the four papers cited by Utiger et al., suggesting that Elaphe is polyphyletic. I had noted that one of the four papers (Dowling et al. 1983) does not contain any Old World species of Elaphe, and therefore the authors have no data to show whether Elaphe is polyphyletic or not. The present paper tested mostly New World species of Elaphe and the Lampropeltine snakes. Dessauer et al. find that snakes now classified in the genera Arizona, Lampropeltis, Rhinocheilus, Bogertophis, Cemophora, Pituophis, Senticolis and Elaphe (obsoleta, vulpina, bairdi, and guttata) are closely related to each other. Elaphe quatuorlineata is the outgroup to this American assemblage. Dessauer et al.'s (1987) data therefore shows that an Eurasian species of Elaphe is ancestral to the North American species of Elaphe and the genera listed above. This is not evidence that Elaphe is polyphyletic at all! This is in fact evidence that all of these American species of snakes are descended from a single species of Eurasian Elaphe.



Dessauer et al. do make the following conclusion on page 28: "Comparative biochemical studies suggest that several widespread colubrid genera are not monophyletic (e.g. Natrix sensu Malnate, 1960; Elaphe; Coluber; Rhadinaea)."



This conclusion can only be reached if the common ancestor of North American Elaphe and Lampropeltis, Arizona, Senticolis, Bogertophis, Pituophis, Stilosoma, Cemophora and Rhinocheilus is not a member of Eurasian Elaphe. But this is unlikely since Elaphe quatuorlineata is basal to this group of American snakes. Since Dessauer (1983) is the third of four papers cited by Utiger et al. as studies suggesting Elaphe is a polyphyletic genus, and it predates this one, the only remaining paper that suggests Elaphe is polyphyletic is that of Minton (1976). It appears that those who are convinced that Elaphe is polyphyletic is left with but one paper as their support.

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