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1.

Background  

The family Accipitridae (hawks, eagles and Old World vultures) represents a large radiation of predatory birds with an almost global distribution, although most species of this family occur in the Neotropics. Despite great morphological and ecological diversity, the evolutionary relationships in the family have been poorly explored at all taxonomic levels. Using sequences from four mitochondrial genes (12S, ATP8, ATP6, and ND6), we reconstructed the phylogeny of the Neotropical forest hawk genus Leucopternis and most of the allied genera of Neotropical buteonines. Our goals were to infer the evolutionary relationships among species of Leucopternis, estimate their relationships to other buteonine genera, evaluate the phylogenetic significance of the white and black plumage patterns common to most Leucopternis species, and assess general patterns of diversification of the group with respect to species' affiliations with Neotropical regions and habitats.  相似文献   

2.
The PCK Clade, represented by six to nine genera, is a monophyletic group situated within the Paniceae tribe. The highly diverse inflorescences within the PCK Clade provide an interesting system for the study of morphological evolution and also may aid in better understanding its unclear systematics. The inflorescence structure of 110 members of the PCK Clade has been investigated. Inflorescences are polytelic showing different levels of truncation. At least 21 different inflorescence subtypes were identified. Fourteen variable inflorescence characters were found, among which some have suprageneric or infrageneric value and others are polymorphic. A key for the identification of inflorescence types is presented. Nine processes have been identified as responsible for inflorescence diversification. Highly branched inflorescences with different internode lengths are present in the basal genus whereas truncated inflorescence morphologies appear late in the history of the clade. The precise timing of morphological changes is impossible to assess until we have a well supported phylogeny for the PCK Clade.  相似文献   

3.
Aim We investigate spatial and temporal patterns of diversification within the Neotropical avifauna using the phylogenetic history of parrots traditionally belonging to the genus Pionopsitta Bonaparte 1854. This genus has long been of interest for those studying Neotropical biogeography and diversity, as it encompasses species that occur in most Neotropical forest areas of endemism. Location The Neotropical lowland forests in South and Central America. Methods Phylogenetic relationships were investigated for all species of the genus Pionopsitta and five other short‐tailed parrot genera using complete sequences of the mitochondrial genes cyt b and ND2 as well as 26 plumage characters. The resulting phylogeny was used to test the monophyly of the genus, investigate species limits, and as a framework for reconstructing their historical biogeography and patterns of diversification. Results We found that the genus Pionopsitta, as previously defined, is not monophyletic and thus the Chocó, Central American and Amazonian species will now have to be placed in the genus Gypopsitta. The molecular and morphological phylogenies are largely congruent, but disagree on the position of one of the Amazon basin taxa. Using molecular sequence data, we estimate that species within Gypopsitta diversified between 8.7 and 0.6 Ma, with the main divergences occurring between 3.3 and 6.4 Ma. These temporal results are compared to other taxa showing similar vicariance patterns. Main conclusions The results suggest that diversification in Gypopsitta was influenced mainly by geotectonic events, marine transgressions and river dynamics, whereas Quaternary glacial cycles of forest change seem to have played a minor role in the origination of the currently recognized species.  相似文献   

4.
5.
DNA phylogenies have gradually shed light on the phylogenetic relationships of the large babbler group. We focus in this study on the family Leiothrichidae (laughingthrushes and “song babblers”), which represents the largest clade of babblers in terms of species diversity. Our phylogeny includes all genera and 82% of the recognized species, using mitochondrial and nuclear loci. The sister group to Leiothrichidae is composed of the Pellorneidae (“jungle babblers”) plus the genus Alcippe. Within Leiothrichidae, four strongly supported primary clades (A–D) are recovered. Clade A includes Grammatoptila, Laniellus and Cutia. Clade B includes a large group of laughingthrushes, all of them classified in Trochalopteron. In Clade C, the two laughingthrushes endemic to southern India, T. fairbanki and T. cachinnans, which have recently been proposed to be placed in the newly erected genus Montecincla, form a sister clade to the group comprising the “song babblers” (Lioptila, Leiothrix, Heterophasia, Minla, Liocichla, Actinodura, Chrysominla, Siva, and Sibia). Clade D includes the African babblers (Turdoides, Phyllanthus, Kupeornis), Asian relatives (Argya, Acanthoptila, Chatarrhaea) and all remaining laughingthrushes (Garrulax). The time estimates suggest that the early diversification of the Leiothrichidae occurred in the mid‐Miocene, a period that corresponds to the diversification of many passerine groups in Asia. A revised taxonomic classification of the family is proposed in the light of these results.  相似文献   

6.
Little information on evolutionary relationships of Neotropical organisms or on the factors that have shaped the diversity currently encountered in this region is available. However, it is clear that biotic interactions and abiotic aspects have played important roles for species diversification in the region. This study focuses on Dolichandra (Bignonieae, Bignoniaceae), a clade of Neotropical lianas that is distributed broadly across different habitats and with diverse pollination and dispersal systems. We used sequences from two plastid DNA markers (ndhF and rpl32‐trnL) and one nuclear gene (PepC) to infer phylogenetic relationships in Dolichandra using parsimony and Bayesian approaches. We then used this phylogenetic framework as basis to study the biogeographic history, reconstruct the evolution of morphological characters and test the impact of morphology and environment on the diversification of the genus. More specifically, we: (1) time‐calibrate the phylogenetic tree of Dolichandra; (2) estimate the ancestral areas of the various lineages; (3) estimate the ancestral states of discrete and continuous morphological traits; (4) test for phylogenetic signal in environmental and phenotypic data; and (5) test whether morphological characters and/or niche evolution are correlated with cladogenesis. All Dolichandra spp. are monophyletic in the combined molecular phylogeny; relationships among species are generally well resolved, although poorly supported in some instances. The genus is inferred to have originated 36.43–26.23 Mya, possibly in eastern South America. Ancestral state reconstructions of continuous and discrete floral characters inferred a mixed morphology as the ancestral condition for the group. Phylogenetic signal differed between perianth and sexual whorls and gradual evolution was recovered for all traits except style length and anther length. Environmental variables showed no phylogenetic signal and a pattern of variation that was not correlated with branch length, suggesting that environmental transitions were concomitant with speciation. Dispersal is inferred to be the main driver of the differential distribution observed among species. In addition, climatic preferences and floral characters seem to have been important reproductive barriers in Dolichandra. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 403–420.  相似文献   

7.
Chironius is one of the most speciose genera of the South American colubrid snakes. Although the genus represents a well‐known radiation of diurnal racers, its monophyly, affinities with other Neotropical colubrid genera, and intrageneric relationships are open questions. Here, we present a phylogenetic analysis of Chironius based on a data matrix that combines one nuclear (c‐mos) and two mitochondrial (12S and 16S rRNA) genes with 37 morphological characters derived from scutellation, skull, and hemipenial features. Phylogenetic relationships were inferred using maximum parsimony (MP) and maximum likelihood (ML). Our combined morphological and molecular analyses strongly support the monophyly of the genus Chironius and its sister‐group relationship with a clade formed by the genera Dendrophidion and Drymobius. Phylogenetic relationships within the genus Chironius is still controversial, although five clades are retrieved with medium to strong support. © 2014 The Linnean Society of London  相似文献   

8.
Klopfstein, S., Quicke, D. L. J., Kropf, C. & Frick, H. (2011) Molecular and morphological phylogeny of Diplazontinae (Hymenoptera, Ichneumonidae). —Zoologica Scripta, 40, 379–402. Parasitoid wasps are among the most species rich and at the same time most understudied of all metazoan taxa. To understand their diversification and test hypotheses about their evolution, we need robust phylogenetic hypotheses. Here, we reconstruct the phylogeny of the subfamily Diplazontinae using four genes and 66 morphological characters both in separate analyses and in a total evidence approach. The resulting phylogeny is highly resolved, with most clades supported by multiple independent data partitions. It contains three highly supported genus groups, for which we suggest morphological and behavioural synapomorphies. The placement of some of the genera, especially Xestopelta Dasch, is unexpected, but also supported by morphology. Most of the genera are retrieved as monophyletic, with the exception of the morphologically diverse genus Syrphoctonus Förster. We split this genus into three genera, including Fossatyloides gen. n., to restore the phylogeny–classification link. Conflict between the morphological and the molecular topology was mostly resolved in favour of the molecular partition in the total evidence approach. We discuss reasons for this finding, and suggest strategies for future taxon and character sampling in Diplazontinae.  相似文献   

9.
Thelypteridaceae is one of the largest families of polypodioid ferns. The generic classification of the family is still controversial because of high levels of convergent or parallel evolution of morphological characters and a lack of molecular phylogenetic studies. In the present study, phylogenetic analyses of three chloroplast regions (rbcL, rps4 and trnL-trnF intergenic spacer region) for 115 taxa, representing 27 recognized segregates in the family, were conducted to explore infrafamilial relationships and gain further understanding of generic boundaries. The phylogenetic reconstructions resolved six distinct clades (Clade I-VI) with strong support. Seven genera: Cyclogramma, Macrothelypteris, Oreopteris, Phegopteris, Pseudophegopteris, Stegnogramma, and Thelypteris are recognized from Clades I, II, IV, and V. In Clade III, Metathelypteris was supported as monophyletic, but the other segregates Amauropelta, Coryphopteris, and Parathelypteris were polyphyletic or paraphyletic, preventing clear recognition of generic boundaries within this clade without additional sampling. Considering great morphological homoplasy within Clade VI, a large genus Cyclosorus is recognized to comprise several small recognized segregates. Within this clade, Pronephrium, and Christella were revealed to be polyphyletic, but several Asian-endemic segregates, such as Glaphyropteridopsis, Mesopteris, and Pseudocyclosorus were strongly supported as monophyletic. Analyses of the evolution of morphological character states on the molecular phylogeny showed extremely high levels of homoplastic evolution for many diagnostic characters.  相似文献   

10.
A mitochondrial DNA (mtDNA) phylogeny of cichlid fish is presented for the most taxonomically inclusive data set compiled to date (64 taxa). 16S rDNA data establish with confidence relationships among major lineages of cichlids, with a general pattern congruent with previous morphological studies and less inclusive molecular phylogenies based on nuclear genes. Cichlids from Madagascar and India are the most basal groups of the family Cichlidae and sister to African–Neotropical cichlids. The cichlid phylogeny suggests drift-vicariance events, consistent with the fragmentation of Gondwana, to explain current biogeographic distributions. Important phylogenetic findings include the placement of the controversial genus Heterochromis basal among African cichlids, the South American genus Retroculus as the most basal taxon of the Neotropical cichlid assemblage, and the close relationship of the Neotropical genera Cichla with Astronotus rather than with the crenicichlines. Based on a large number of South American genera, the Neotropical cichlids are defined as a monophyletic assemblage and shown to harbor significantly higher levels of genetic variation than their African counterparts. Relative rate tests suggest that Neotropical cichlids have experienced accelerated rates of molecular evolution. But these high evolutionary rates were significantly higher among geophagine cichlids. Received: 18 September 1998 / Accepted: 16 December 1998  相似文献   

11.
The Augochlorini Beebe is a New World tribe of bees comprising 663 described species. Relationships among the genera of this monophyletic tribe remain uncertain. Here I provide a comprehensive phylogeny using morphological and molecular information. In all, 54 Augochlorini species plus 16 outgroups and 3017 molecular and 105 morphological characters were analysed. Sequences for four genes were analysed using Bayesian inference, maximum likelihood and parsimony. Morphological characters were taken from a literature review and analysed alone and in combination with molecular data using parsimony. The monophyly of Augochlorini and most genera is confirmed, with divergence of the main lineages of the tribe around 55–20 Ma. Seven clades were supported by most analyses and are here treated as genus‐level groups, as follows (combined analysis topology): (Corynura group, (Chlerogella group, (Rhinocorynura group, (Augochloropsis, (Megaloptidia group, (Neocorynura group, (Augochlora group, Megalopta group))))))). According to this topology, dim‐light foraging and cleptoparasitism arose three times in the tribe. According to my hypothesis, the diversification of Augochlorini may have begun as a response to vicariant events, including the split of the Neotropical/Andean regions and marine transgressions in the Amazon region.  相似文献   

12.
运用广义形态学性状对虎尾草亚科(Chloridoideae)进行系统发育分析。内类群包括虎尾草亚科52属的69种植物,代表虎尾草亚科的主要类群;芦竹亚科(Arundinoideae)扁芒草族(Danthonieae)的Centropodia和Danthonia被选作外类群。分支分析表明,虎尾草亚科是一个单系类群。其严格一致树包括A、B、C、D、E5个分支。两个大族画眉草族(Eragrostideae)和虎尾草族(Chlorideae)代表虎尾草亚科内部类群分化的两个方向,分开处理较合理。细穗草族(Leptureae)放到虎尾草族中较合理。冠芒草族(Pappophoreae)是虎尾草亚科的基部类群,与画眉草族近缘。我们的研究支持虎尾草亚科从旧世界向新世界扩散的地理分布假说,并提供了虎尾草亚科属上类群的系统发育关系的框架。  相似文献   

13.
Orchid bees (Euglossini) are spectacular long-tongued Neotropical bees important in the pollination of Neotropical long-corolla flowers, particularly some orchids. Besides remarkably long tongues, males in particular exhibit other flower-related adaptations, including setal brushes on the foretarsi used for rasping the petals of orchids while collecting aromatic compounds. These compounds are stored in large swollen tibiae and are thought to play an important role in courtship behavior. Euglossini are also unusual in lacking sociality; they are the only tribe among the corbiculate bees that are not eusocial, and two of the genera are cleptoparasitic. Each genus exhibits distinct behavioral traits including nest architecture and host-parasite interactions, yet their evolution is unknown. Despite previous phylogenetic studies of on morphological characters, the relationships among the five euglossine genera remain under debate. We investigate euglossine generic relationships using DNA sequence data from four genes and new morphological characters. The morphological and molecular data yield congruent evolutionary patterns, and combining the data gives a fully resolved and well supported phylogeny of Euglossini.  相似文献   

14.
To investigate forces influencing diversification in Neotropical fishes, the phylogenetic relationships among species and populations of the cichlid genus Cichla were examined. Mitochondrial DNA was sequenced for 454 individuals of the 5 nominal Cichla species and several putative undescribed species. Phylogenetic analyses support the distinction of two major clades of Cichla. Clade A includes C. temensis and two undescribed species from the lower Amazonas and Xingu Rivers. Clade B includes C. orinocensis, C. monoculus, C. ocellaris. C, intermedia, and an undescribed species from the upper Madeira River. Species boundaries were relatively well-circumscribed for clade B, while incomplete lineage sorting was inferred for clade A. Three probable instances of introgression were observed, including a regional population of C. orinocensis from the Negro River that shows a history of introgression. Biogeographic patterns from Cichla are partially congruent with those seen in several other Neotropical fish clades, and the diversification of Cichla species is inferred to result from both vicariance and sympatric divergence.  相似文献   

15.
The Nes subgroup of the Gobiosomatini (Teleostei: Gobiiformes: Gobiidae) is an ecologically diverse clade of fishes endemic to the tropical western Atlantic and eastern Pacific oceans. It has been suggested that morphological characters in gobies tend to evolve via reduction and loss associated with miniaturization, and this, coupled with the parallel evolution of adaptations to similar microhabitats, may lead to homoplasy and ultimately obscure our ability to discern phylogenetic relationships using morphological characters alone. This may be particularly true for the Nes subgroup of gobies, where several genera that are diagnosed by ‘reductive characters’ have been shown to be polyphyletic. Here we present the most comprehensive phylogeny to date of the Nes subgroup using mitochondrial and nuclear sequence data. We then evaluate the congruence between the distribution of morphological characters and our molecular tree using maximum‐likelihood ancestral state reconstruction, and test for phylogenetic signal in characters using Pagel's λ tree transformations (Nature, 401 , 1999 and 877). Our results indicate that all of the characters previously used to diagnose genera of the Nes subgroup display some degree of homoplasy with respect to our molecular tree; however, many characters display considerable phylogenetic signal and thus may be useful in diagnosing genera when used in combination with other characters. We present a new classification for the group in which all genera are monophyletic and in most cases diagnosed by combinations of morphological characters. The new classification includes four new genera and nine new species described here, many of which were collected from rarely sampled deep Caribbean reefs using manned submersibles. The group now contains 38 species in the genera Carrigobius gen. nov., Chriolepis, Eleotrica, Gobulus, Gymneleotris, Nes, Paedovaricus gen. nov., Pinnichthys gen. nov., Psilotris, and Varicus. Lastly, we provide a key to all named species of the Nes subgroup along with photographs and illustrations to aid in identification.  相似文献   

16.
17.
The orchid bees constitute a clade of prominent insect pollinators distributed throughout the Neotropical region. Males of all species collect fragrances from natural sources, including flowers, decaying vegetation and fungi, and store them in specialized leg pockets to later expose during courtship display. In addition, orchid bees provide pollination services to a diverse array of Neotropical angiosperms when foraging for food and nesting materials. However, despite their ecological importance, little is known about the evolutionary history of orchid bees. Here, we present a comprehensive molecular phylogenetic analysis based on ~4.0 kb of DNA from four loci [cytochrome oxidase (CO1), elongation factor 1‐α (EF1‐α), arginine kinase (ArgK) and RNA polymerase II (Pol‐II)] across the entire tribe Euglossini, including all five genera, eight subgenera and 126 of the approximately 200 known species. We investigated lineage diversification using fossil‐calibrated molecular clocks and the evolution of morphological traits using disparity‐through‐time plots. In addition, we inferred past biogeographical events by implementing model‐based likelihood methods. Our dataset supports a new view on generic relationships and indicates that the cleptoparasitic genus Exaerete is sister to the remaining orchid bee genera. Our divergence time estimates indicate that extant orchid bee lineages shared a most recent common ancestor at 27–42 Mya. In addition, our analysis of morphology shows that tongue length and body size experienced rapid disparity bursts that coincide with the origin of diverse genera (Euglossa and Eufriesea). Finally, our analysis of historical biogeography indicates that early diversification episodes shared a history on both sides of Mesoamerica, where orchid bees dispersed across the Caribbean, and through a Panamanian connection, thus reinforcing the hypothesis that recent geological events (e.g. the formation of the isthmus of Panama) contributed to the diversification of the rich Neotropical biota. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 552–572.  相似文献   

18.
DNA sequences of the 5' end of the chloroplast ndhF gene for 15 species of Caryophyllaceae have been analyzed by parsimony and neighbor-joining analyses. Three major clades are identified, with little or no support for monophyly of traditionally recognized subfamilies. The first of the three major clades identified (Clade I) is constituted by part of the subfamily Paronychioideae. It includes members of the tribe Paronychieae and members of tribe Polycarpeae. The second (Clade II) contains members of the Paronychieae exclusively. Tribe Paronychieae is thus apparently polyphyletic and tribe Polycarpeae is at least paraphyletic. The third clade (Clade III) includes members of subfamilies Alsinoideae and Caryophylloideae along with the genus Spergularia. The genus Scleranthus is also part of Clade III, while Drymaria groups with the other genera of tribe Polycarpeae in Clade II. We conclude that morphological characters previously used to delimit subfamilial groupings in the Caryophyllaceae are apparently unreliable estimators of phylogeny.  相似文献   

19.
The marmosets, tribe Callitrichini, are the most speciose clade in the subfamily Callitrichinae, containing 21 species. However, there is no consensus among molecular and morphological systematists as to how many genera should be recognized for the group. To test the morphological support for the alternative generic classifications, this study presents a comprehensive phylogenetic analysis. It is the first such analysis to include all 21 species and employ continuous and discrete osteological, pelage and tegument, karyological and vocal characters. This dataset was combined with nucleotide sequences from two mitochondrial and four nuclear regions. Separate analyses showed that, among morphological datasets, osteological characters were best at solving relationships at more inclusive levels, whilst pelage characters were most informative at the interspecific level. This suggests the presence of different transformation rates for the two character sets. When a single most parsimonious tree was obtained using the 83‐character matrix, three main clades were identified, supporting the division of the marmosets into three genera: Callithrix, Cebuella and Mico. The total evidence analysis that included an additional 3481 molecular characters corroborated most of the morphology‐based clades and also supported a three‐genus classification of the marmosets. This is the first morphological study to support an Amazonian marmoset clade (Cebuella Mico), which is also strongly supported in exclusively molecular phylogenies, and to synonimize Callibella under Mico.  相似文献   

20.
The evolution of Neotropical birds of open landscapes remains largely unstudied. We investigate the diversification and biogeography of a group of Neotropical obligate grassland birds (Anthus: Motacillidae). We use a multilocus phylogeny of 22 taxa of Anthus to test the hypothesis that these birds radiated contemporaneously with the development of grasslands in South America. We employ the R package DDD to analyze the dynamics of Anthus diversification across time in Neotropical grasslands, explicitly testing for shifts in dynamics associated with the Miocene development of grasslands, the putative Pleistocene expansion of arid lowland biomes, and Pleistocene sundering of Andean highland grasslands. A lineage‐through‐time plot revealed increases in the number of lineages, and DDD detected shifts to a higher clade‐level carrying capacity during the late Miocene, indicating an early burst of diversification associated with grassland colonization. However, we could not corroborate the shift using power analysis, probably reflecting the small number of tips in our tree. We found evidence of a divergence at ~1 Mya between northern and southern Amazonian populations of Anthus lutescens, countering Haffer's idea of Pleistocene expansion of open biomes in the Amazon Basin. We used BioGeoBears to investigate ancestral areas and directionality of colonization of Neotropical grasslands. Members of the genus diversified into, out of, and within the Andes, within‐Andean diversification being mostly Pleistocene in origin.  相似文献   

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