Search

The Rufous Potoo (Nyctibius bracteatus Gould, 1846) is the smallest member of the family Nyctibiidae, which comprises seven species endemic to the Neotropical region. Morphologically, it is highly distinct from its congeners, not only in its smaller size, but also in possessing a strange marking on its iris and having entirely rufous plumage, which is lightly vermiculated and has pronounced white spots on the wing coverts, breast, belly, flanks and undertail coverts. Molecular studies have shown extraordinarily high levels of genetic divergence amongst potoo species, and a recent genome-scale molecular phylogeny of potoo species placed N. bracteatus as sister to all other potoos with high confidence. Similarly, osteological data reveal that the species has several unique and plesiomorphic characters. Therefore, its distinctive morphology, in combination with unique behavioral traits, and its recurrent placement as the earliest branching terminal in phylogenetic treatments of the family, convinced us to erect a new genus for the species, Phyllaemulor. [ABSTRACT FROM AUTHOR]

The temporal origins of the extraordinary biodiversity of the Neotropical region are highly debated. Recent empirical work has found support for alternative models on the tempo of speciation in Neotropical species further fuelling the debate. However, relationships within many Neotropical lineages are poorly understood, and it is unclear how this uncertainty impacts inferences on the evolution of taxa in the region. We examined the robustness of diversification patterns in the avian genus Forpus by testing whether the use of different units of biodiversity (i.e. biological species and statistically inferred species) impacted diversification rates and inferences regarding important biogeographic breaks in the genus. We found that the best-fit model of diversification for the biological species data set was a declining rate of diversification; whereas a model of constant diversification was the best-fit model for statistically inferred species or subspecies. Moreover, the relative importance of different landscape features in delimiting genetic structure across the landscape varied across data sets with differing units of biodiversity. Patterns based on divergence times among biological species indicated old speciation events across major geographic and river barriers. In contrast, data sets more inclusive of the diversity in Forpus illustrate the role of both old divergence across major landscape features and more recent divergences that are possibly attributed to Pleistocene climatic changes. Overall, these results indicate that conflicting models on the temporal origins of Neotropical birds may be attributable to sampling biases. [ABSTRACT FROM AUTHOR]

Abstract: The Thamnophilidae is a diverse radiation of insectivorous passerine birds that comprises nearly 220 species and is mostly restricted to the lowlands and lower montane forests of the Neotropics. Current classification within Thamnophilidae relies primarily on morphological variation, but recent incorporation of molecular and vocal data has promoted changes at various taxonomic levels. Here we demonstrate that the genus Terenura is polyphyletic because Terenura callinota, T. humeralis, T. spodioptila, and T. sharpei are phylogenetically distant from the type species of the genus, Terenura maculata. More importantly, the former four species are not particularly closely related to any other thamnophilids and represent a clade that is sister to all other members of the family. Because no genus name is available for this previously undetected lineage in the Thamnophilidae, we describe the genus Euchrepomis for callinota, humeralis, spodioptila, and sharpei, and erect the subfamily Euchrepomidinae. We discuss the taxonomic and evolutionary significance of this divergent lineage. This study highlights the importance of taxonomic coverage and the inclusion of type taxa to redefine classifications to reflect accurately evolutionary relationships. [Copyright &y& Elsevier]

Clytoctantes atrogularis Lanyon, Stotz and Willard, 1990 (Thamnophilidae) is one of the most mysterious and poorly known birds of the Neotropics. Endemic to Amazonian Brazil, it was known only from the holotype and two sight records at the type locality in Rondônia, and a sighting of a pair with a recording on the Sucunduri River in Amazonas. Here we review the distribution and report five new records in the states of Mato Grosso, Amazonas, and Rondônia, considerably increasing the known range of the species. We present the first detailed descriptions of males, for which the plumage was previously unknown. The records presented herein were made in terra firme forest with understories dominated by Lepidocaryum palms and also with sparse Guadua spp. of bamboo, demonstrating that the bird species occurs in habitats other than those previously described. Stomach contents of six individuals included mostly ants and their eggs, possibly obtained by opening stems of Guadua spp. The high rate of deforestation that characterizes a large part of the range of C. atrogularis could be causing declines in local populations. [ABSTRACT FROM AUTHOR]