Multiple connections between Amazonia and Atlantic Forest shaped the phylogenetic and morphological diversity of Chiasmocleis Mehely, 1904 (Anura: Microhylidae: Gastrophryninae).

Chiasmocleis is the most species-rich genus of Neotropical microhylids. Herein, we provide the first comprehensive multilocus phylogeny for the genus, including all but 3 of the 34 recognized species and multiple individuals per species. We discuss cryptic speciation, species discovery, patterns of morphological evolution, and provide a historical biogeographic analysis to account for the current distribution of the genus. Diversification of Chiasmocleis from other New World microhylids began during the Eocene, app. 40 mya, in forested areas, and current diversity seems to be a product of recurrent connections between the Atlantic Forest and Amazonia. Small-sized species evolved independently three times in Chiasmocleis. Furthermore, the extremely small-bodied (i.e. miniaturized) species with associated loss of digits, phalanges, and pectoral girdle cartilages evolved only once and are restricted to Amazonia. Using the phylogeny, we recognized three subgenera within Chiasmocleis: Chiasmocleis Méhely, 1904, Relictus subg. nov., and Syncope Walker, 1973. The recognition of the subgenus Syncope informs future research on patterns of miniaturization in the genus, and the subgenus Relictus highlights isolation of an endemic and species-poor lineage to the Atlantic Forest, early (about 40 mya) in the history of Chiasmocleis.

Molecular insights into the phylogenetic placement of the poorly known genus Niceforonia Goin Cochran, 1963 (Anura: Brachycephaloidea).

Among New World direct-developing frogs belonging to the clade Brachycephaloidea (= Terraranae), there are several genera with uncertain phylogenetic placements. One notable example is the genus Niceforonia Goin Cochran 1963, which includes three species that are endemic to Colombia. Three specimens of the species Niceforonia nana were collected and for the first time the genus is included in a molecular phylogenetic analysis of mitochondrial (mtDNA; 12S and 16S) and nuclear (nucDNA; TYR and RAG1) markers. Molecular phylogenetic inference based on concatenated and separate mtDNA and nucDNA analyses recovered Niceforonia nana nested within Hypodactylus Hedges et al. 2008, rendering the latter genus paraphyletic. Consequently, herein we place the genus Hypodactylus in the synonymy of Niceforonia to resolve the paraphyly and place Niceforonia in the subfamily Hypodactylinae. Based on our revised concept of the genus Niceforonia we conducted preliminary morphological comparisons using specimens and literature descriptions. Finally, Nicefornia nana is quite divergent from other species of Niceforonia (uncorrected genetic distances of ca. 10% 16S and 7% TYR) suggesting that further taxonomic revision may be warranted.