As I said, it is most likely that Hyla eximia is the most basal member of US Hyla and their closest relatives, given its geographic location and morphology and given the virtual certainty that the genus Hyla originated in the neotropics (vs. for example the nearctic or palearctic). Moriarty and Cannatella's tree surprisingly shows Hyla chrysoscelis as the most basal member, which is problematic, since 2 of Hedges' 3 trees show that Hyla eximia is the most basal species (fig. 1a and 1b of Moriarty and Cannatella). Further, Hyla crucifer has traditionally been considered a species of Hyla on the basis of morphology. Yet their maximum likelihood tree has H. crucifer nested deeply within Pseudacris, a group of degenerate hylids with reduced toe pads. That placement is not parsimonious, since it requires an evolutionary reversal for H. crucifer to have descended from an ancestor with reduced toe pads. Their maximum parsimony tree shows that H. crucifer forming an unresolved polytomy with 2 other groups of species traditionally placed in Pseudacris. Moriarty and Cannatella's parsimony tree therefore seems to make more sense than their likelihood tree. Their parsimony tree is also closer to the immunological data, which you dismiss casually because of its age.

According to immunological data, Hyla crucifer is basal to Pseudacris and Hyla regilla and Hyla cadaverina are in turn basal to H. crucifer. da Silva's tree also shows the same topology and both of these contradict Moriarty and Cannatella's likelihood tree. Using da Silva's tree, one can certainly recognize a holophyletic Pseudacris while leaving Hyla cadaverina, H. regilla and H. crucifer outside of Pseudacris. Hyla is paraphyletic whether we accept Moriarty and Cannatella's classification or not. Therefore, why create heterogeneity within Pseudacris by including several treefrogs that have been traditionally classified within Hyla? Why do so if there is a danger of having Pseudacris invalidated? Moriarty and Cannatella's reason for doing so (i.e. they are following most checklists and field guides) is dubious. The reason why Pseudacris has been recognized as being distinct from Hyla is the reduced toe pads of this group of secondarily terrestrial hylids. By including Hyla crucifer, Hyla regilla and H. cadaverina, all of which have well developed toe pads, the genus Pseudacris becomes undefinable and undiagnosable, notwithstanding Hedges' claim that his "Pseudacris" has a "cold-weather breeding season, a round or ovoid testis, and a black pigment covering on the testis." Breeding season is not a taxonomic character. The shape of the testis and the presence of dark pigment only apply to the males of these species. The reduced toe pads are diagnostic of both sexes.

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