Comparative chloroplast genomics and insights into the molecular evolution of Tanaecium (Bignonieae, Bignoniaceae).

Species of Tanaecium (Bignonieae, Bignoniaceae) are lianas distributed in the Neotropics and centered in the Amazon. Members of the genus exhibit exceptionally diverse flower morphology and pollination systems. Here, we sequenced, assembled, and annotated 12 complete and four partial chloroplast genomes representing 15 Tanaecium species and more than 70% of the known diversity in the genus. Gene content and order were similar in all species of Tanaecium studied, with genome sizes ranging between 158,470 and 160,935 bp. Tanaecium chloroplast genomes have 137 genes, including 80-81 protein-coding genes, 37 tRNA genes, and four rRNA genes. No rearrangements were found in Tanaecium plastomes, but two different patterns of boundaries between regions were recovered. Tanaecium plastomes show nucleotide variability, although only rpoA was hypervariable. Multiple SSRs and repeat regions were detected, and eight genes were found to have signatures of positive selection. Phylogeny reconstruction using 15 Tanaecium plastomes resulted in a strongly supported topology, elucidating several relationships not recovered previously and bringing new insights into the evolution of the genus.

An updated synopsis of Tanaecium (Bignonieae, Bignoniaceae).

Tanaecium Sw. emend L.G. Lohmann (Bignonieae, Bignoniaceae) is a genus of Neotropical lianas that is morphologically variable, especially in floral features. The genus is distributed from Mexico and the Antilles to Argentina, and centered in Amazonia. Here, we present an updated overview for Tanaecium that recognizes 21 species within the genus. Species delimitation was based on a detailed analysis of protologues and herbarium specimens, including type collections of all taxa. We present a detailed description for the genus and a key for the identification of all species. For each of the 21 species recognized, we present information on the nomenclature, phenology, habitat, distribution, and taxonomic notes. Furthermore, Spathicalyx kuhlmannii J.C. Gomes is transferred into Tanaecium kuhlmannii (J.C. Gomes) Frazão & L.G. Lohmann. A lectotype is proposed for Tanaecium crucigerum Seem.

The Gondwana Breakup and the History of the Atlantic and Indian Oceans Unveils Two New Clades for Early Neobatrachian Diversification.

The largest anuran diversity belongs to the Neobatrachia, which harbor more than five thousand extant species. Here, we propose a new hypothesis for the historical aspects of the neobatrachian evolution with a formal biogeographical analysis. We selected 12 genes for 144 neobatrachian genera and four archaeobatrachian outgroups and performed a phylogenetic analysis using a maximum likelihood algorithm with the rapid bootstrap test. We also estimated divergence times for major lineages using a relaxed uncorrelated clock method. According to our time scale, the diversification of crown Neobatrachia began around the end of the Early Cretaceous. Our phylogenetic tree suggests that the first split of Neobatrachia is related to the geological events in the Atlantic and Indian Oceans. Hence, we propose names for these clades that indicate this connection, i.e., Atlanticanura and Indianura. The Atlanticanura is composed of three major neobatrachian lineages: Heleophrynidae, Australobatrachia and Nobleobatrachia. On the other hand, the Indianura consists of two major lineages: Sooglossoidea and Ranoides. The biogeographical analysis indicates that many neobatrachian splits occurred as a result of geological events such as the separation between South America and Africa, between India and the Seychelles, and between Australia and South America.