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We present a new phylogenetic hypothesis for Ischnocnema, a Neotropical brachycephaloid genus of ground-dwelling direct-developing frogs. We performed Bayesian inference, maximum likelihood, and maximum parsimony analyses using two nuclear (RAG1 and Tyr) and three mitochondrial genes (12S rRNA, tRNA-Val, and 16S rRNA) in a matrix comprising more than 80% of the described species. We recover Ischnocnema nanahallux outside the Ischnocnema parva series, and it is now unassigned to any species series, nor are Ischnocnema manezinho and Ischnocnema sambaqui. We propose the Ischnocnema venancioi species series to comprise Ischnocnema venancioi, Ischnocnema hoehnei, and two new species described herein (Ischnocnema parnaso sp. nov. and Ischnocnema colibri sp. nov.). Furthermore, we designate a lectotype for I. venancioi. The nuptial pad present in males is an important character in the genus, and having a large, conspicuous, and glandular-appearing nuptial pad seems to be a synapomorphy for the clade composed of the I. parva, Ischnocnema guentheri, and the newly proposed I. venancioi series.

A large proportion of the biodiversity of Amazonia, one of the most diverse rainforest areas in the world, is yet to be formally described. One such case is the Neotropical frog genus Adenomera. We here evaluate the species richness and historical biogeography of the Adenomera heyeri clade by integrating molecular phylogenetic and species delimitation analyses with morphological and acoustic data. Our results uncovered ten new candidate species with interfluve-associated distributions across Amazonia. In this study, six of these are formally named and described. The new species partly correspond to previously identified candidate lineages ‘sp. F’ and ‘sp. G’ and also to previously unreported lineages. Because of their rarity and unequal sampling effort of the A. heyeri clade across Amazonia, conservation assessments for the six newly described species are still premature. Regarding the biogeography of the A. heyeri clade, our data support a northern Amazonian origin with two independent dispersals into the South American Dry Diagonal. Although riverine barriers have a relevant role as environmental filters by isolating lineages in interfluves, dispersal rather than vicariance must have played a central role in the diversification of this frog clade.

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Recent biological discoveries have changed our understanding of the distribution and evolution of neotropical biotas. In the Brazilian Atlantic Forest, the discovery of closely related species isolated on distant mountains has led to the hypothesis that the ancestors of montane species occupied and dispersed through lowland regions during colder periods. This process may explain the distribution of an undescribed Anolis lizard species that we recently discovered at a montane site in the Serra dos Órgãos National Park, a popular tourist destination close to the city of Rio de Janeiro. To investigate whether this species is closely related to other Atlantic Forest montane anoles, we implement phylogenetic analyses and divergence time estimation based on molecular data. We infer the new species nested within the Dactyloa clade of Anolis, forming a clade with A. nasofrontalis and A. pseudotigrinus, two species restricted to montane sites about 400 km northeast of Serra dos Órgãos. The new species diverged from its sister A. nasofrontalis around 5.24 mya, suggesting a cold-adapted lowland ancestor during the early Pliocene. Based on the phylogenetic results, we emend the definitions of the series taxa within Dactyloa, recognizing a clade containing the new species and several of its relatives as the nasofrontalis series. Lastly, we provide morphological data supporting the recognition of the new species and give it a formal scientific name. Future studies are necessary to assess how park visitors, pollutants, and shrinking montane habitats due to climate change will affect this previously overlooked anole species.