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In the last decade, studies in bird breeding biology have shown that infidelity is prevalent in socially monogamous species. Here, we describe an extra-pair copulation (EPC) event in the Rufous Hornero (Furnarius rufus), a socially monogamous bird with year-round territoriality and low levels of extra-pair paternity. Before the EPC, a within-pair copulation (WPC) occurred inside the pairs territory. The WPC occurred on the ground and between a banded male (ca. 6 years-old) and an unbanded female. Ten minutes later this breeding pair invaded a neighboring territory, presumably to forage. The territorial male was chased back to its territory by an unbanded male neighbor after being detected. The male neighbor was paired with an unbanded female that did not participate in the aggressive interaction. When flying back to its territory the male neighbor copulated with the territorial female on the ground (ie. EPC). The territorial male flew, vocalized, and perched above the male neighbor, interrupting the EPC. The aggressive interaction then ceased as each pair resumed foraging in their respective territories. These observations suggest that Rufous Horneros can use EPC to obtain immediate benefits (food access in a neighbors territory). Moreover, WPC may be detected by neighbors and physical mate guarding and/or frequent WPC may be necessary to prevent EPC in the Rufous Hornero.(AU)

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The Pernambuco Center of Endemism (PCE) is the northernmost strip of the Atlantic Forest (AF). Biogeographic affinities among avifaunas in the PCE, the southern-central Atlantic Forest (SCAF), and Amazonia (AM) have not been studied comprehensively, and current patterns of genetic diversity in the PCE remain unclear. The interplay between species' ecological attributes and historical processes, such as Pleistocene climate fluctuations or the appearance of rivers, may have affected population genetic structures in the PCE. Moreover, the role of past connections between the PCE and AM and the elevational distribution of species in assembling the PCE avifauna remain untested. Here, we investigated the biogeographic history of seven taxa endemic to the PCE within a comparative phylogeographic framework based on a mean of 3,618 independent single nucleotide polymorphisms (SNPs) extracted from flanking regions of ultraconserved elements (UCEs) and one mitochondrial gene. We found that PCE populations were more closely related to SCAF populations than they were to those in AM, regardless of their elevational range, with divergence times placed during the Mid-Pleistocene. These splits were consistent with a pattern of allopatric divergence with gene flow until the upper Pleistocene and no signal of rapid changes in population sizes. Our results support the existence of a Pleistocene refugium driving current genetic diversity in the PCE, thereby rejecting the role of the São Francisco River as a primary barrier for population divergence. Additionally, we found that connections with Amazonia also played a significant role in assembling the PCE avifauna through subsequent migration events.

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Informações sobre a biologia reprodutiva da maioria das aves neotropicais e comparações interpopulacionais são insuficientes. O Manakin de Capacete, Antilophia galeata(Lichtenstein, 1823), é um passeriforme de sub-bosque comumente encontrado nas matas de galeria do bioma Cerrado tipo savana tropical. Fornecemos informações sobre a fenologia de nidificação, ciclo de nidificação, ninhos, ovos, filhotes e características do local de nidificação de uma população de Manakin-de-capacete no estado de São Paulo, sudeste do Brasil. Durante duas estações reprodutivas encontramos 16 ninhos ativos e 30 ninhos inativos. As atividades reprodutivas ocorreram de meados de agosto a meados de janeiro, e os ninhos foram construídos em arbustos e mudas no sub-bosque da floresta, 0,45-3,48 m acima do solo (1,56 ± 0,66 m). O tamanho da ninhada foi de dois ovos, que foram colocados em intervalos de um a três dias. Foram observados três padrões notáveis ​​de variação de coloração e marcação dos ovos entre as ninhadas. O período de incubação de dois ninhos foi de 18 e 19 dias, e os períodos de nidificação foram de 16,3 ± 0. 6 dias (16-17 dias, n = 3 ninhos). A sobrevivência aparente do ninho de 11 ninhos cuidadosamente monitorados foi de 36,4%. Além da primeira descrição das variações do padrão de ovos entre ninhadas, as seguintes informações diferem dos dados anteriores da literatura: intervalo de postura e períodos de nidificação. Nossos dados contribuem para o conhecimento geral das variações nos parâmetros de reprodução do Manakin de Capacete.(AU)

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Introducción: Coccyzus ferrugineus es el ave endémica menos estudiada de la Isla del Coco se desconocen muchos aspectos sobre su historia natural y comportamiento, siendo de las especies menos conocidas en Costa Rica. Objetivo: Describir el comportamiento reproductivo, de forrajeo, y el uso de hábitat de C. ferrugineus para generar información para la toma de decisiones de conservación de la especie. Métodos: Se hicieron observaciones directas de comportamiento (forrajeo, cortejo, vocalización, alimentación y cópula) durante dos periodos de observación (mañana y tarde), en parcelas entre los 0-400 m de altitud, clasificando el estrato de vegetación (bajo-medio-alto) para estudiar el uso de hábitat. Se presenta una descripción del comportamiento de forrajeo y del ciclo reproductivo. Resultados: Se demuestra que C. ferrugineus utiliza todo el gradiente altitudinal de la Isla del Coco, desde el nivel del mar hasta los 400 m de altitud en el bosque nuboso, para reproducirse y su época reproductiva está marcada por el inicio de la época seca. No se encontraron diferencias significativas entre las categorías de comportamiento establecidas y la hora del día (Fisher, P > 0.05). Sin embargo sí se mostró diferencias significativas para las categorías de comportamiento y el estrato vertical (Fisher, P < 0.05) demostrando que utiliza todo el estrato vertical de la estructura vegetal. Conclusiones: Este estudio representa la base para el conocimiento de la biología reproductiva e historia natural de C. ferrugineus, es urgente realizar más estudios sobre esta especie para poder protegerla y conservar el ecosistema terrestre de la Isla del Coco.

Introducción: Coccyzus ferrugineus is the least studied endemic bird of Isla del Coco, many aspects of its natural history and behavior remain unknown, being one the least known species in Costa Rica. Objective: To describe the reproductive behavior, foraging and habitat use of C. ferrugineus to generate information for making conservation decisions for the species. Methods: Direct behavioral observations (foraging, courtship, vocalization, feeding and intercourse) were made in plots between 0-400 m above sea level, during two observation periods (morning and afternoon). A description of the foraging behavior and the reproductive cycle is presented. Results: C. ferrugineus uses the entire altitudinal gradient of the island to reproduce, from sea level to 400 m altitude in the cloud forest. Its reproductive season is marked by the beginning of the dry season. No significant differences were found between the established behavior categories and the time of day (Fisher, P> 0.05). However, significant differences were shown for the behavioral categories and the vertical stratum (Fisher, P <0.05) demonstrating that it uses the entire vertical stratum of the vegetation structure. Conclusions: This study represents the basis for the knowledge of the reproductive biology and natural history of C. ferrugineus, it is urgent to carry out more studies on this species to be able to protect it and conserve the terrestrial ecosystem of Isla del Coco.

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Comparative phylogeography is a powerful approach to investigate the role of historical and environmental processes in the evolution of biodiversity within a region. In this regard, comparative studies of species with similar habitat preferences are valuable to reduce the confounding influence of habitat association when interpreting phylogeographic patterns. In the Atlantic Forest of South America, phylogeographic studies of highland and lowland species have shown distinct population structure patterns so far, suggesting that such species have responded differently to Pleistocene glacial cycles. Herein, we performed a comparative analysis using molecular data and paleodistribution models of two Montane Atlantic Forest (MAF) co-distributed passerine birds with similar habitat requirements but with distinct life-history traits and ecologies: the frugivore lek-breeding Blue Manakin (Chiroxiphia caudata) and the insectivore and socially monogamous Drab-Breasted Bamboo Tyrant (Hemitriccus diops). We aimed to shed light on the role of contrasting life histories and ecologies onto the demography and population structure of MAF species. We sampled both species throughout most of their distribution range, sequenced a mitochondrial and a nuclear molecular marker, and used standard phylogeographic methods to investigate population structure and ecological niche modeling (ENM) to infer the species' paleodistributions. Our analyses recovered a phylogeographic break in H. diops in the region of the Doce River, but no genetic structure in C. caudata. We also found higher differentiation among subpopulations within each lineage of H. diops than among subpopulations of C. caudata. We suggest that these discrepancies in population structure might be due to distinct life-history traits and their impact on gene flow and generation time. For example, while H. diops is an insectivore species, C. caudata is a frugivore and the latter ecological aspect likely selects for a higher dispersion distance. Additionally, because C. caudata is a lek-breeding species, it has a longer generation time than H. diops. These traits could hinder genetic differentiation when populations become geographically isolated. Nonetheless, both species showed some common biological features, such as signatures of synchronous population expansion and larger distribution ranges during the Last Glacial Maximum, possibly due to similar cold tolerance.

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The Neotropics show a wealth of distributional patterns shared by many co-distributed species. A distinctive pattern is the so-called "circum-Amazonian distribution," which is observed in species that do not occur in Amazonia but rather along a belt of forested habitats spanning south and east of Amazonia, the Andean foothills, and often into the Venezuelan Coastal Range and the Tepuis. Although this pattern is widespread across animals and plants, its underlying biogeographic mechanisms remain poorly understood. The Variable Antshrike (Thamnophilus caerulescens) is a sexually dimorphic suboscine passerine that exhibits extreme plumage variation and occurs along the southern portion of the circum-Amazonian belt. We describe broad-scale phylogeographic patterns of T. caerulescens and assess its demographic history using DNA sequences from the mitochondrion and ultraconserved elements (UCEs). We identified three genomic clusters: a) northern Atlantic Forest; b) southeastern Cerrado and central-southern Atlantic Forest, and c) Chaco and Andes. Our results were consistent with Pleistocene divergence followed by gene flow, mainly between the latter two clusters. There were no genetic signatures of rapid population expansions or bottlenecks. The population from the northern Atlantic Forest was the most genetically divergent group within the species. The demographic history of T. caerulescens was probably affected by series of humid and dry periods throughout the Quaternary that generated subtle population expansions and contractions allowing the intermittent connection of habitats along the circum-Amazonian belt. Recognizing the dynamic history of climate-mediated forest expansions, contractions, and connections during the South American Pleistocene is central toward a mechanistic understanding of circum-Amazonian distributions.

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In Brazil, species of the genus Ramphocelus with the presence of various endoparasites have already been reported. Coccidia have been the parasites most frequently found. All species of this genus have similar habitats and ecological niches, which makes parasite transmission easy. The aim of this study was to diagnose the presence of endoparasites in fecal samples from specimens of Ramphocelus carbo that were caught in the Cazumbá-Iracema Extractive Reserve (Cazumbá Resex), in the State of Acre. The specimens (n = 30) were caught in mist nets arranged in different ecosystems of the Reserve. After identification, the bird specimens were placed in cloth bags for a maximum of 30 minutes to collect feces. Among the 22 samples collected, 63.63% (n = 14) were positive for endoparasites. The coccidia were the parasites most frequently. Helminths belonging to Ascaridiidae (Nematoda), Strongylida (Nematoda) and Davaneidae (Cestoda) were recorded for the first time in R. carbo in the State of Acre. Parasites belonging to Strongylida and Davaneidae were recorded for the first time in a species of Ramphocelus. These findings add information on the parasitic fauna of wild birds, since in the Amazon region there are few studies on this subject.

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The aim of this study was to investigate the presence of shiga toxin-producing Escherichia coli (STEC) and atypical enteropathogenic Escherichia coli (aEPEC) in frozen chicken carcasses sold at stores in southern Brazil. Typical E. coli colonies were enumerated in 246 chicken carcasses, and the presence of stx1, stx2, eae genes was investigated in their rinse liquid and in E. coli strains isolated from those carcasses. Strains of E. coli were also investigated for the presence of bfp gene. A median of 0.6 cfu.g-1(ranging from 0.1 to 242.7 cfu.g-1) of typical E. coli colonies was found in the carcasses. Shiga toxin-encoding genes (stx1 and stx2) were not detected, indicating that the chicken carcasses were negative for STEC. The intimin protein gene (eae) was detected in E.coli isolated from 4.88% of the carcasses; all tested strains were negative for the bfp gene and were classified as aEPEC. Twenty-two aEPEC strains were tested for resistance to ten antimicrobials and subjected to macrorestriction (PFGE). All the tested aEPEC strains were fully susceptible to cephalosporins, ciprofloxacin and colistin. Resistance to sulfonamide (65%), ampicillin (55%), tetracycline (50%) and gentamicin (45%) were the most frequent. The PFGE profile demonstrated a low level of similarity among the resistant strains, indicating that they were epidemiologically unrelated. The results indicate that aEPEC strains can contaminate chicken meat, and their association with strains implicated in human diarrhea needs to be further investigated.(AU)

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Normal passerines (n=216) were evaluated for oocysts of Isospora in feces at the Triage Center for Wild Animals (CETAS, IBAMA, Belo Horizonte; August 21 to September 21, 2012). The positive samples with oocysts represented 13.0% of Cardinalidae (n=23), 11.2% of Emberizidae (n=107), 50% of Icteridae (n=10) and 60.3% of Thraupidae (n=68). The probability of fecal oocysts attributable to the host in Thraupidae is higher than in Cardinalidae, Emberizidae, Fringillidae and Turdidae, but similar to Icteridae. No oocysts were found in Fringillidae and Turdidae. Within Thraupidae, Isospora was for the first time described in Paroaria dominicana and Schistochlamys ruficapillus and within Icteridae, in Gnorimopsar chopi. Saltator similis presented a higher risk, 66.9% greater than Lanio pileatus and Sporophila caerulescens and with a 27.9% greater probability than Sporophila nigricolis. The new coccidian species described were Isospora dominicana [ellipsoid oocysts, 25 (30-20) x 25 (28-20) µm] in Paroaria dominicana; Isospora beagai [ovoid oocysts, 28 (32-17) x 25 (29-16) µm] and Isospora ferri [ellipsoid oocysts, 20 (22-16) x 18 (22-15) µm] in Saltator similis; Isospora ruficapillus [spheric to subspherical oocysts, 25 (26-23) x 24 (25-21) µm] in Schistochlamys ruficapillus; and Isospora chopi [spherical to sub-spherical oocysts, 24.5 x 22 (30-20 x 25-20) µm] and Isospora gnorimopsar [sub-spherical to ovoid oocysts, 27 x 23 (32-22 x 28-20) µm] in Gnorimopsar chopi. The morphometry and features were compared with previously described Isospora in passerines. New coccidian species and new passerine hosts are described for Isospora and recommends for constant monitoring during rehabilitation, especially for the hosts of Thraupidae and Icteridae.(AU)

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Normal passerines (n=216) were evaluated for oocysts of Isospora in feces at the Triage Center for Wild Animals (CETAS, IBAMA, Belo Horizonte; August 21 to September 21, 2012). The positive samples with oocysts represented 13.0% of Cardinalidae (n=23), 11.2% of Emberizidae (n=107), 50% of Icteridae (n=10) and 60.3% of Thraupidae (n=68). The probability of fecal oocysts attributable to the host in Thraupidae is higher than in Cardinalidae, Emberizidae, Fringillidae and Turdidae, but similar to Icteridae. No oocysts were found in Fringillidae and Turdidae. Within Thraupidae, Isospora was for the first time described in Paroaria dominicana and Schistochlamys ruficapillus and within Icteridae, in Gnorimopsar chopi. Saltator similis presented a higher risk, 66.9% greater than Lanio pileatus and Sporophila caerulescens and with a 27.9% greater probability than Sporophila nigricolis. The new coccidian species described were Isospora dominicana [ellipsoid oocysts, 25 (30-20) x 25 (28-20) µm] in Paroaria dominicana; Isospora beagai [ovoid oocysts, 28 (32-17) x 25 (29-16) µm] and Isospora ferri [ellipsoid oocysts, 20 (22-16) x 18 (22-15) µm] in Saltator similis; Isospora ruficapillus [spheric to subspherical oocysts, 25 (26-23) x 24 (25-21) µm] in Schistochlamys ruficapillus; and Isospora chopi [spherical to sub-spherical oocysts, 24.5 x 22 (30-20 x 25-20) µm] and Isospora gnorimopsar [sub-spherical to ovoid oocysts, 27 x 23 (32-22 x 28-20) µm] in Gnorimopsar chopi. The morphometry and features were compared with previously described Isospora in passerines. New coccidian species and new passerine hosts are described for Isospora and recommends for constant monitoring during rehabilitation, especially for the hosts of Thraupidae and Icteridae.

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The aim of this study was to investigate the presence of shiga toxin-producing Escherichia coli (STEC) and atypical enteropathogenic Escherichia coli (aEPEC) in frozen chicken carcasses sold at stores in southern Brazil. Typical E. coli colonies were enumerated in 246 chicken carcasses, and the presence of stx1, stx2, eae genes was investigated in their rinse liquid and in E. coli strains isolated from those carcasses. Strains of E. coli were also investigated for the presence of bfp gene. A median of 0.6 cfu.g-1(ranging from 0.1 to 242.7 cfu.g-1) of typical E. coli colonies was found in the carcasses. Shiga toxin-encoding genes (stx1 and stx2) were not detected, indicating that the chicken carcasses were negative for STEC. The intimin protein gene (eae) was detected in E.coli isolated from 4.88% of the carcasses; all tested strains were negative for the bfp gene and were classified as aEPEC. Twenty-two aEPEC strains were tested for resistance to ten antimicrobials and subjected to macrorestriction (PFGE). All the tested aEPEC strains were fully susceptible to cephalosporins, ciprofloxacin and colistin. Resistance to sulfonamide (65%), ampicillin (55%), tetracycline (50%) and gentamicin (45%) were the most frequent. The PFGE profile demonstrated a low level of similarity among the resistant strains, indicating that they were epidemiologically unrelated. The results indicate that aEPEC strains can contaminate chicken meat, and their association with strains implicated in human diarrhea needs to be further investigated.

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Abstract Nasal mites (Mesostigmata: Rhinonyssidae) are obligatory endoparasites of birds, and the resulting parasitism can be harmful to the host's respiratory system. The nasal mite Sternostoma tracheacolum Lawrence has caused significant respiratory issues, including serious injuries that possibly cause death of the host. In this study, we report two cases of captive birds parasitized by S. tracheacolum. The first case is a histopathological description of S. tracheacolum parasitizing the Gouldian Finch (Chloebia gouldiae) in the southeast region of Brazil, that showed partially or totally absence of the characteristic respiratory epithelium in trachea lumen. The other describes, for the first time, the parasitism of this species in a canary (Serinus canaria) in the northeast region of the country.

Resumo Os ácaros nasais (Mesostigmata: Rhinonyssidae) são endoparasitos obrigatórios das aves, e este parasitismo pode ser prejudicial ao sistema respiratório de seu hospedeiro. A espécie de ácaro nasal Sternostoma tracheacolum Lawrence tem causado importantes problemas respiratórios, incluindo lesões graves que possivelmente causam a morte do hospedeiro. Neste estudo, relatamos dois casos de aves em cativeiro parasitadas por S. tracheacolum. O primeiro caso é uma descrição histopatológica de S. tracheacolum parasitando um Diamante-de-gould (Chloebia gouldiae) na região sudeste do Brasil, mostrando parcial ou total ausência do epitélio respiratório característico do lúmen da traqueia. O outro descreve, pela primeira vez, o parasitismo desta espécie em um canário (Serinus canaria) na região nordeste do país.

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Nasal mites (Mesostigmata: Rhinonyssidae) are obligatory endoparasites of birds, and the resulting parasitism can be harmful to the host's respiratory system. The nasal mite Sternostoma tracheacolum Lawrence has caused significant respiratory issues, including serious injuries that possibly cause death of the host. In this study, we report two cases of captive birds parasitized by S. tracheacolum. The first case is a histopathological description of S. tracheacolum parasitizing the Gouldian Finch (Chloebia gouldiae) in the southeast region of Brazil, that showed partially or totally absence of the characteristic respiratory epithelium in trachea lumen. The other describes, for the first time, the parasitism of this species in a canary (Serinus canaria) in the northeast region of the country.

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Dendrocincla woodcreepers are ant-following birds widespread throughout tropical America. Species in the genus are widely distributed and show little phenotypic variation. Notwithstanding, several subspecies have been described, but the validity of some of these taxa and the boundaries among them have been discussed for decades. Recent genetic evidence based on limited sampling has pointed to the paraphyly of D. fuliginosa, showing that its subspecies constitute a complex that also includes D. anabatina and D. turdina. In this study we sequenced nuclear and mitochondrial markers for over two hundred individuals belonging to the D. fuliginosa complex to recover phylogenetic relationships, describe intraspecific genetic diversity and provide historical biogeographic scenarios of diversification. Our results corroborate the paraphyly of D. fuliginosa, with D. turdina and D. anabatina nested within its recognized subspecies. Recovered genetic lineages roughly match the distributions of described subspecies and congruence among phylogenetic structure, phenotypic diagnosis and distribution limits were used to discuss current systematics and taxonomy within the complex, with special attention to Northern South America. Our data suggest the origin of the complex in western Amazonia, associated with the establishment of upland forests in the area during the early Pliocene. Paleoclimatic cycles and river rearrangements during the Pleistocene could have, at different times, both facilitated dispersal across large Amazonian rivers and the Andes and isolated populations, likely playing an important role in differentiation of extant species. Previously described hybridization in the headwaters of the Tapajós river represents a secondary contact of non-sister lineages that cannot be used to test the role of the river as primary source of diversification. Based on comparisons of D. fuliginosa with closely related understory upland forest taxa, we suggest that differential habitat use could influence diversification processes in a historically changing landscape, and should be considered for proposing general mechanisms of diversification.

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Even though nest architecture has been useful for phylogenetic inferences among the Thamnophilidae (Aves: Passeriformes), the nests of only three out of five species of Myrmoderus (Ridgway, 1909) are known to science. Here we describe the nests, eggs, and nestling of the Squamate Antbird Myrmoderus squamosus (Pelzeln, 1868). Two nests were bulky bottom-supported cups, measuring 7.3 and 12 cm in maximum outside diameter, with a noticeably smaller egg cup, and they were placed within the crown of short, broad-leafed plants. Eggs were short-oval, with chalky white background color, and purple blotches and streaks more concentrated in the large end. One nestling was dark reddish grey, with bluish white feet, pinkish gray tarsi, and a blackish bill with bright yellow rictal flanges. In face of the great diversity of nest types found among the Thamnophilidae, we concluded that the nest of M. squamosus was similar to those of other congeners, giving support to this currently phylogenetically-defined genus.(AU)

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A long-held view in evolutionary biology is that character displacement generates divergent phenotypes in closely related coexisting species to avoid the costs of hybridization or ecological competition, whereas an alternative possibility is that signals of dominance or aggression may instead converge to facilitate coexistence among ecological competitors. Although this counterintuitive process-termed convergent agonistic character displacement-is supported by recent theoretical and empirical studies, the extent to which it drives spatial patterns of trait evolution at continental scales remains unclear. By modelling the variation in song structure of two ecologically similar species of Hypocnemis antbird across western Amazonia, we show that their territorial signals converge such that trait similarity peaks in the sympatric zone, where intense interspecific territoriality between these taxa has previously been demonstrated. We also use remote sensing data to show that signal convergence is not explained by environmental gradients and is thus unlikely to evolve by sensory drive (i.e. acoustic adaptation to the sound transmission properties of habitats). Our results suggest that agonistic character displacement driven by interspecific competition can generate spatial patterns opposite to those predicted by classic character displacement theory, and highlight the potential role of social selection in shaping geographical variation in signal phenotypes of ecological competitors.

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The West Indian avifauna has provided fundamental insights into island biogeography, taxon cycles, and the evolution of avian behavior. Our interpretations, however, should rely on robust hypotheses of evolutionary relationships and consistent conclusions about taxonomic status in groups with many endemic island populations. Here we present a phylogenetic study of the West Indian thrashers, tremblers, and allies, an assemblage of at least 5 species found on 29 islands, including what is considered the Lesser Antilles' only avian radiation. We improve on previous phylogenetic studies of this group by using double-digest restriction site-associated DNA sequencing (ddRAD-seq) to broadly sample loci scattered across the nuclear genome. A variety of analyses, based on either nucleotide variation in 2223 loci recovered in all samples or at 13,282 loci confidently scored as present or absent in all samples, converged on a single well-supported phylogenetic hypothesis. Results indicate that the resident West Indian taxa form a monophyletic group, exclusive of the Neotropical-Nearctic migratory Gray Catbird Dumetella carolinensis, which breeds in North America; this outcome differs from earlier studies suggesting that Gray Catbird was nested within a clade of island resident species. Thus, our findings imply a single colonization of the West Indies without the need to invoke a subsequent 'reverse colonization' of the mainland by West Indian taxa. Additionally, our study is the first to sample both endemic subspecies of the endangered White-breasted Thrasher Ramphocinclus brachyurus. We find that these subspecies have a long history of evolutionary independence with no evidence of gene flow, and are as genetically divergent from each other as other genera in the group. These findings support recognition of R. brachyurus (restricted to Martinique) and the Saint Lucia Thrasher R. sanctaeluciae as two distinct, single-island endemic species, and indicate the need to re-evaluate conservation plans for these taxa. Our results demonstrate the utility of phylogenomic datasets for generating robust systematic hypotheses.

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Even though nest architecture has been useful for phylogenetic inferences among the Thamnophilidae (Aves: Passeriformes), the nests of only three out of five species of Myrmoderus (Ridgway, 1909) are known to science. Here we describe the nests, eggs, and nestling of the Squamate Antbird Myrmoderus squamosus (Pelzeln, 1868). Two nests were bulky bottom-supported cups, measuring 7.3 and 12 cm in maximum outside diameter, with a noticeably smaller egg cup, and they were placed within the crown of short, broad-leafed plants. Eggs were short-oval, with chalky white background color, and purple blotches and streaks more concentrated in the large end. One nestling was dark reddish grey, with bluish white feet, pinkish gray tarsi, and a blackish bill with bright yellow rictal flanges. In face of the great diversity of nest types found among the Thamnophilidae, we concluded that the nest of M. squamosus was similar to those of other congeners, giving support to this currently phylogenetically-defined genus.

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Glyphorynchus spirurus (GSP), also called the Wedge-billed Woodcreeper (Furnariidae) has an extensive distribution in the Americas, including the Atlantic coast of Brazil. Nevertheless, there is no information about its karyotype or genome organization. To contribute to the knowledge of chromosomal evolution in Passeriformes we analysed the karyotype of Glyphorynchus spirurus by classic and molecular cytogenetics methods. We show that Glyphorynchus spirurus has a 2n = 80 karyotype with a fundamental number (FN) of 84, similar to the avian putative ancestral karyotype (PAK). Glyphorynchus spirurus pair 1 was heteromorphic in the Tapajós population whereby the short arms varied in sizes, possibly due to a pericentric inversion, as described in other Furnariidae birds. FISH with the Histone H5 probe revealed a signal in the pericentromeric region of G. spirurus chromosome 5 and rDNA 18S showed interstitial signal in GSP-1. Chromosome painting with Gallus gallus (GGA) macrochromosomes 1-9 probes showed disruption of chromosome syntenies of GGA-1, 2 and 4 by fission in Glyphorynchus spirurus. Our results confirm that the GGA1 centric fission is a synapomorphic character for the phylogenetic branch composed of Strigiformes, Passeriformes, Columbiformes and Falconiformes. On the other hand, the GGA-2 fission is reported here for the first time in Passeriformes. Chromosome painting with BOE whole chromosome probes confirmed these rearrangements in Glyphorynchus spirurus revealed by Gallus gallus 1-9 probes, in addition to enabling the establishment of genome-wide homology map.

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Establishing links between phenotypic and genotypic variation is a central goal of evolutionary biology, as they might provide important insights into evolutionary processes shaping genetic and species diversity in nature. One of the more intriguing possibilities is when no genetic divergence is found to be associated with conspicuous phenotypic divergence. In that case, speciation theory predicts that phenotypic divergence may still occur in the presence of significant gene flow-thereby resulting in little genomic divergence-when genetic loci underpinning phenotypes are under strong divergent selection. However, a finding of phenotypic distinctiveness with weak or no population genetic structure may simply result from low statistical power to detect shallow genetic divergences when small data sets are used. Here, we used a subgenomic data set of 2,386 ultraconserved elements to explore genomewide divergence between two species of Antilophia manakins, which are phenotypically distinct yet evidently lack strong genetic differentiation according to previous studies based on a limited number of loci. Our results revealed clear population structure that matches the two phenotypes, supporting the idea that smaller data sets lacked the power to detect this recent divergence event (likely <100 k ya). Indeed, we found little or no introgression between the species, as well as evidence of genomewide divergence. One implication of our study is that the Araripe plateau may be a hot spot of cryptic-diverging forest Cerrado populations. Besides their use in biogeography, subgenomic data sets may help redefine local conservation programmes by revealing cryptic population structure that may be key to population management.

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