For the record, DHL stopped responding to my posts when I pointed out that Hyla eximia is most likely the ancestral species and/or morphotype from which all holarctic hylids evolved, given its biogeography and the morphological similarity between Hyla regilla, Hyla arborea and Hyla eximia and their large immunological distances. I thought that DHL had disappeared from this forum but he proved that he did not when he responded instead to Patrick Alexander's off topic personal attack, which alleges that I somehow reject data from Hennigians and that I also reject data that are published since the 1980's. I have since shown that Patrick Alexander's claims are baseless and easily contradicted in a different part of this thread.

Returning to the problem of classifying Hyla regilla, it is also possible that Hyla regilla was the species that evolved out of the node from which Hyla arborea also evolved. This is supported by immunological data by Maxson and Wilson, published in 1974 in the journal Science, which shows that some island populations of Hyla regilla are almost as distant immunologically from mainland populations of Hyla regilla as they are from Hyla eximia. Such data shows that Hyla regilla is an old species, and that it is morphologically conservative. Cladistic ideology assumes that an ancestor automatically becomes extinct when new species arise. But evolutionary biologists who have studied speciation extensively know that new species often form by the process of budding, or peripatric speciation. That means a small isolated population evolved into a new species while the ancestral species continues to live largely unchanged. If Pseudacris and Hyla crucifer had evolved by budding off of Hyla regilla, that would mean that the entire Hyla regilla-Pseudacris-Hyla crucifer branch is in fact Hyla regilla. Since this branch shares the same ancestor as Hyla arborea and Hyla eximia, putting Hyla regilla in Pseudacris also mean that Hyla arborea and Hyla eximia must also be transferred into Pseudacris in order to avoid making Pseudacris a paraphyletic genus. DHL contends that Moriarty and Cannatella's mtDNA data is the best available. I asked him/her how he/she made that determination but received no response. Whether or not Moriarity and Cannatella's data is the best available, the plain fact is that Moriarty and Cannatella did not include Hyla arborea in their analysis. They therefore cannot refute Maxson and Wilson's immunological data. That means their analysis cannot be used to show that Pseudacris is a valid genus that excludes Hyla arborea. Further studies are needed to clarify this point, but the available data does indeed show that the inclusion of Hyla regilla (and Hyla cadaverina) in Pseudacris is an unwise idea taxonomically. Of course their inclusion also makes Pseudacris too heterogeneous to be meaningful, notwithstanding Moriarty and Cannatella's claim that this genus can be redefined on the morphology of their testes.

Since R. C. Stebbins' new field guide excludes both H. regilla and H. cadaverina from Pseudacris, there should be no rush to adopt Moriarty and Cannatella's taxonomic arrangement, since they themselves are merely following checklists and field guides. Stebbins' arrangement also makes more sense because the traditional definition is that Pseudacris is a monophyletic group characterized by reduced toe pads, which are the result of a secondarily terrestrial existence. Excluding Hyla regilla and Hyla cadaverina from Pseudacris preserves this definition without making Pseudacris any less of a monophyletic group. Only those who like to make classifications so heterogeneous as to be useless would stubbornly insist on including Hyla regilla and Hyla cadaverina in Pseudacris.

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