No abstract

The Neotropical hylid genus Sphaenorhynchus includes 15 species of small, greenish treefrogs widespread in the Amazon and Orinoco basins, and in the Atlantic Forest of Brazil. Although some studies have addressed the phylogenetic relationships of the genus with other hylids using a few exemplar species, its internal relationships remain poorly understood. In order to test its monophyly and the relationships among its species, we performed a total evidence phylogenetic analysis of sequences of three mitochondrial and three nuclear genes, and 193 phenotypic characters from all species of Sphaenorhynchus. Our results support the monophyly of Sphaenorhynchus with molecular and phenotypic evidence, with S. pauloalvini as the earliest diverging taxon, followed by S. carneus, as the sister taxon of all remaining species of the genus. We recognize three species groups in Sphaenorhynchus (the S. lacteus, S. planicola and S. platycephalus groups), to facilitate its taxonomic study; only three species (S. carneus, S. pauloalvini and S. prasinus) remain unassigned to any group. Sequence data were not available for only two species (S. bromelicola and S. palustris) for which we scored phenotypic data; wildcard behaviour was detected only in S. bromelicola nested inside the S. platycephalus group. On the basis of the resulting phylogenetic hypothesis, we discuss the evolution of oviposition site and a number of phenotypic characters that could be associated with heterochronic events in the evolutionary history of this group.

We present a molecular phylogenetic analysis of the hylid tribe Hylini, with the goals of testing the monophyly of the genera Duellmanohyla, Isthmohyla, and Ptychohyla and providing a discussion on the monophyly of Bromeliohyla, Charadrahyla, Ecnomiohyla, Exerodonta, Megastomatohyla, and Sarcohyla. Our results indicate the paraphyly of Ptychohyla, with Bromeliohyla and Duellmanohyla nested within it, and, as in previous analyses, the paraphyly of Duellmanohyla (due to Ptychohyla legleri and P. salvadorensis being nested within it). To resolve this situation, we restrict the contents of Ptychohyla, redelimit those of Duellmanohyla and Bromeliohyla, and erect two new genera, one to include the former Ptychohyla panchoi and P. spinipollex, and the other for the former Ptychohyla acrochorda, P. sanctaecrucis, P. zoque, and tentatively, P. erythromma. Exerodonta as currently defined is not monophyletic, inasmuch as Exerodonta juanitae is nested within Charadrahyla. Consequently, we transfer this species and, tentatively, E. pinorum to Charadrahyla. Also, we discuss some possible taxonomic problems within Exerodonta. Our results indicate that Isthmohyla is polyphyletic, the bromeliad-dwelling Isthmohyla melacaena being the sister taxon of our only exemplar of Bromeliohyla, B. bromeliacia. For this reason, we transfer I. melacaena to Bromeliohyla, rendering Isthmohyla monophyletic. The former Isthmohyla pictipes Group is shown to be paraphyletic due to having the non-monophyletic I. pseudopuma Group within it. Accordingly, we recognize a redelimited I. pseudopuma Group (contents: I. infucata and I. pseudopuma), an I. zeteki Group (contents: I. picadoi and I. zeteki), and a newly defined I. tica Group (contents: I. angustilineata, I. calypsa, I. debilis, I. graceae, I. lancasteri, I. pictipes, I. tica, I. rivularis, and, tentatively, I. insolita and I. xanthosticta). The three groups of Isthmohyla are supported by molecular evidence with jackknife support values > 90%, and two of them by putative morphological synapomorphies. We discuss the recognition of Dryophytes, Hyliola, Rheohyla, and Sarcohyla and whether it is useful to recognize Anotheca, Diaglena, and Triprion as three distinct, monotypic genera. Finally, we discuss a recent taxonomic proposal involving changes in rank and from ranked to unranked names in hylids that overall we consider to have been poorly justified and only superficially discussed.