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Philorea Erichson, 1834 (Pimeliinae: Physogasterini) is a South American endemic genus of the Desert, Puna and Atacaman biogeographic provinces, in the territories of Peru, Bolivia and Chile. The objective of this work was to update the knowledge of the genus in the Peruvian territory, providing a checklist of species and new distribution records. From examination of 821 specimens, a total of 15 species of Philorea are recorded for Peru. Also distributions maps and comments about its distribution patterns are provided. [ABSTRACT FROM AUTHOR]

Summary: The biogeography of neotropical fungi remains poorly understood. Here, we reconstruct the origins and diversification of neotropical lineages in one of the largest clades of ectomycorrhizal fungi in the globally widespread family Russulaceae.We inferred a supertree of 3285 operational taxonomic units, representing worldwide internal transcribed spacer sequences. We reconstructed biogeographic history and diversification and identified lineages in the Neotropics and adjacent Patagonia.The ectomycorrhizal Russulaceae have a tropical African origin. The oldest lineages in tropical South America, most with African sister groups, date to the mid‐Eocene, possibly coinciding with a boreotropical migration corridor. There were several transatlantic dispersal events from Africa more recently. Andean and Central American lineages mostly have north‐temperate origins and are associated with North Andean uplift and the general north–south biotic interchange across the Panama isthmus, respectively. Patagonian lineages have Australasian affinities. Diversification rates in tropical South America and other tropical areas are lower than in temperate areas.Neotropical Russulaceae have multiple biogeographic origins since the mid‐Eocene involving dispersal and co‐migration. Discontinuous distributions of host plants may explain low diversification rates of tropical lowland ectomycorrhizal fungi. Deeply diverging neotropical fungal lineages need to be better documented. [ABSTRACT FROM AUTHOR]

This correction notice addresses missing references and clarifications in an article titled "Predicting the distribution of plant species from southern South America: are the hotspots of genetic diversity threatened by climate change?" The missing reference, Fremout et al. 2020, should have been included in the article and the citation for this reference should have been included in the section on species distribution modeling. Additionally, a sentence in the seventh paragraph should have included a reference to the blockCV package for R. The publisher, Springer Nature, remains neutral in terms of jurisdictional claims and institutional affiliations. The authors of the article are Carolina Soliani, Viviana Ceccarelli, María Victoria Lantschner, Evert Thomas, and Paula Marchelli. [Extracted from the article]

This work presents an updated list of the species belonging to the genus Phaseolus following its definition of 1978; it is the outcome of the study of eighty-six herbaria and forty-one explorations in the field in the period 1978–2019. There are currently eighty-one species, all of them native to the Americas, most of them distributed north of Panama (the genus is a migrant into South America), and half of them being known by very few records. They thrive in warm to mild temperate, seasonally dry, open forest, with rains under favorable temperature, from sea level up to 3,000 m. The recent increase in the number of recognized species is due to the endemic ones; this in combination with few unclassified specimens may indicate that the total number of species is not final yet, and that field work will be rewarding. [ABSTRACT FROM AUTHOR]

Background and Aims Cunoniaceae are woody plants with a distribution that suggests a complex history of Gondwanan vicariance, long-distance dispersal, diversification and extinction. Only four out of ~27 genera in Cunoniaceae are native to South America today, but the discovery of extinct species from Argentine Patagonia is providing new information about the history of this family in South America. Methods We describe fossil flowers collected from early Danian (early Palaeocene, ~64 Mya) deposits of the Salamanca Formation. We compare them with similar flowers from extant and extinct species using published literature and herbarium specimens. We used simultaneous analysis of morphology and available chloroplast DNA sequences (trnL – F , rbcL , matK , trnH – psbA) to determine the probable relationship of these fossils to living Cunoniaceae and the co-occurring fossil species Lacinipetalum spectabilum. Key Results Cunoniantha bicarpellata gen. et sp. nov. is the second species of Cunoniaceae to be recognized among the flowers preserved in the Salamanca Formation. Cunoniantha flowers are pentamerous and complete, the anthers contain in situ pollen, and the gynoecium is bicarpellate and syncarpous with two free styles. Phylogenetic analysis indicates that Cunoniantha belongs to crown-group Cunoniaceae among the core Cunoniaceae clade, although it does not have obvious affinity with any tribe. Lacinipetalum spectabilum , also from the Salamanca Formation, belongs to the Cunoniaceae crown group as well, but close to tribe Schizomerieae. Conclusions Our findings highlight the importance of West Gondwana in the evolution of Cunoniaceae during the early Palaeogene. The co-occurrence of C. bicarpellata and L. spectabilum , belonging to different clades within Cunoniaceae, indicates that the diversification of crown-group Cunoniaceae was under way by 64 Mya. [ABSTRACT FROM AUTHOR]

Premise: Eocene floras of Patagonia document biotic response to the final separation of Gondwana. The conifer genus Araucaria, distributed worldwide during the Mesozoic, has a disjunct extant distribution between South America and Australasia. Fossils assigned to Australasian Araucaria Sect. Eutacta usually are represented by isolated organs, making diagnosis difficult. Araucaria pichileufensis E.W. Berry, from the middle Eocene Río Pichileufú (RP) site in Argentine Patagonia, was originally placed in Sect. Eutacta and later reported from the early Eocene Laguna del Hunco (LH) locality. However, the relationship of A. pichileufensis to Sect. Eutacta and the conspecificity of the Araucaria material among these Patagonian floras have not been tested using modern methods. Methods: We review the type material of A. pichileufensis alongside large (n = 192) new fossil collections of Araucaria from LH and RP, including multi‐organ preservation of leafy branches, ovuliferous complexes, and pollen cones. We use a total evidence phylogenetic analysis to analyze relationships of the fossils to Sect. Eutacta. Results: We describe Araucaria huncoensis sp. nov. from LH and improve the whole‐plant concept for Araucaria pichileufensis from RP. The two species respectively resolve in the crown and stem of Sect. Eutacta. Conclusions: Our results confirm the presence and indicate the survival of Sect. Eutacta in South America during early Antarctic separation. The exceptionally complete fossils significantly predate several molecular age estimates for crown Eutacta. The differentiation of two Araucaria species demonstrates conifer turnover during climate change and initial South American isolation from the early to middle Eocene. [ABSTRACT FROM AUTHOR]

Large‐scale anthropogenic changes to landscapes will cause species to move and shift their ranges against a backdrop of international political boundaries. Transboundary conservation efforts are therefore key to preserving intact and connected landscapes, particularly if such efforts can be implemented within the framework of protected area networks that provide for resiliency and persistence in the face of threats such as climate change. We studied the distribution, connectivity, and integrity of protected areas in regions near international borders within the Americas. We found that there is a greater proportion of land protected near vs. far from borders, with this effect extending approximately 125 km from the border. This trend was most pronounced when considering multiuse categories of protected areas in the analysis. We also found that there is greater connectivity of protected areas in border regions than more internally within countries, and relatively low rates of habitat loss within border‐situated and internal protected areas. Our results indicate that protected area networks are larger and more connected if considered in a transboundary context and that efforts to conserve species and mitigate effects of long‐term stressors like climate change will be most successful when planning includes neighboring countries. Despite a relative lack of attention to transboundary conservation in the Americas, our results suggest substantial opportunities for linking landscapes via a focus on international border regions and coordination across borders in protected areas management. [ABSTRACT FROM AUTHOR]

Cerrado is a biodiversity hotspot composed of a vegetation mosaic landscape ranging from grasslands to forests. It holds a high endemicity of plants and vertebrate species suffering from high habitat destruction rates. We aimed at characterizing the mutualistic interactions between bats and the plant species present in their diet in the different habitats of the Cerrado to determine which habitats should be prioritized for the conservation of most bat-plant interactions. In order to do that, we assessed two datasets, one covering all interactions between bats and plants in Latin America and the other with the distribution of plant species across the 13 different Cerrado habitats and the Cerrado as a whole. Forests played the major role in the structure of the interactions as they hold the highest number of interactions, with a big percentage being unique to these habitats. The removal of forests in our simulations led to a high dissimilarity of the original structure of the interactions and the extinction of 1/3 of all bat species. Special attention must be given to key habitats such as gallery forests as they not only help connecting the landscape, but also hold a large proportion of the interactions between bats and plants in the Cerrado and play an important role on the network structure between bats and plants in the heterogeneous Cerrado landscapes. [ABSTRACT FROM AUTHOR]

With increasing availability of plant distribution data, the information about global plant diversity is improving rapidly. Recently, Ulloa Ulloa et al. (2017) presented the first comprehensive overview of the native vascular flora of the Americas, yielding a total count of 124,993 native species. Of these, 51,241 occur in North America and 82,052 in South America. By combining these data with the information in the Global Naturalized Alien Flora (GloNAF) database of naturalized alien floras, we point out that for a complete picture of the regional and continental plant richness, the naturalized alien species need to be considered. Ignoring this novel component of regional floras can lead to an inaccurate picture of overall change in biodiversity in the Anthropocene. We show that North and South America might face contrasting challenges in terms of potential threats to biodiversity posed by alien plant species, because of the different past and present dynamics of invasions and predictions of future development. In total, there are 7,042 naturalized alien plants occurring in the Americas, with 6,122 recorded in North America and 2,677 in South America; if only introductions from other continents are considered additions to the native continental flora make up 6.9 and 1.4 %, respectively. Nevertheless, predictions of naturalized plant trajectories based on global trade dynamics and climate change suggest that considerable increases in naturalized plant numbers are expected in the next 20 years for emerging South American economies, which could reverse the present state. [ABSTRACT FROM AUTHOR]

The Pantanal is located in the center of South America in a tectonically active sedimentary basin of Quaternary age. Even though the relief is flat and the diversity of the sediments is low, its vegetation cover has high variability resulting from seasonal fluctuations in water levels and the presence of four surrounding biomes. Changes in elevation of less than 1 m influence the length and intensity of floods, powerfully affecting the vegetation. Faults with small vertical displacement can generate abrupt vegetation changes and, consequently, expressive vegetation lineaments. This study characterizes a lineament in the northern Pantanal, considering Land Surface Phenology, estimates of precipitation, and floristic survey. The phenological metrics, obtained from a 15-year time series from the Moderate Resolution Imaging Spectroradiometer processed by TIMESAT software, discriminate evergreen forests in the NW of this lineament from savanna-like physiognomies in the SE region. Plant taxonomic identification shows two distinct regional strata with a clear separation between species adapted to prolonged floods in the NW and typical species of the Cerrado biome, mostly xeromorphic, in the SE. Data from the Tropical Rainfall Measuring Mission complemented the analysis, showing different dependence on local rains on different sides of the lineament. The entire dataset defines this geological structure as a driver of the Pantanal's plant communities, being a boundary for the extensive establishment of propagules of the Amazon biome. This research, in addition to advancing knowledge of this singular region, which is essential for management studies, can be a stimulus to biological and forest investigations. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The high biodiversity of northern South America is unparalleled and includes several centres of diversity such as Amazonia, the Andes and the Chocó. Movement of lineages amongst and within these bioregions is thought to be rare, and the effect of those dispersals on the distribution, diversity, and community assembly remains poorly understood. Here we address these effects by studying divergence times, biogeographical history, and species diversification of the palm tribe Iriarteeae, an ecologically dominant forest component. Location: Central and South America. Methods: We developed a calibrated phylogeny and a spatially explicit diversification model that incorporates molecular and fossil data. In these analyses, we included a new fossil Iriartea species Gemmamonocolpites galeanoana, derived from new samples of Miocene deposits in western Amazonia. We also estimated the geographical range evolution of lineages and tested whether speciation and extinction rates were affected by dispersal events using a simulation approach in ClaSSE. Results: Dispersal amongst bioregions was not evenly distributed across the topology. We found that Amazonian communities are overdispersed across the phylogeny, whereas Andean taxa are clustered. Dispersal events were associated with increases in species diversification and were concomitant with periods of Andean uplift. Migration into montane areas occurred several times from lowland Amazonian ancestors, and montane taxa subsequently recolonized the Amazonian bioregion. Main conclusions: Our results suggest that the diversification of Iriarteeae palms closely followed the west‐to‐east surface uplift history of the Northern Andes. From an early, lowland Amazonian ancestor, the first diversification events took place in the earliest emerging mountain chain, the Western Cordillera. From there multiple range expansions followed eastwards and back into the lowlands. This study demonstrates how geological events within a single mountain range can affect the geographical expansion and diversification of lineages. [ABSTRACT FROM AUTHOR]

Cheilanthoid ferns (Cheilanthoideae sensu PPG 1 2016) constitute an important group within the Pteridaceae and are cosmopolitan in distribution. In South America, there are 155 species distributed in 13 genera, among which the largest are Adiantopsis (35), Cheilanthes (27), and Doryopteris (22). Most of the cheilanthoid species are morphologically adapted to grow in arid to semi-arid conditions and show convergent evolution, which has implied difficulties in defining the genera throughout their taxonomic history (Copeland 1947, Tryon & Tryon 1973, Gastony & Rollo 1995, 1998, Kirkpatrick Systematic Botany, 32: 504-518, 2007, Rothfels et al. Taxon, 57: 712-724, 2008). Here, we sequenced two plastid markers (rbcL + trnL-F) of 33 South American cheilanthoid species, most of which have not been included in phylogenetic analyses previously. The South American species were analyzed together with South African and Australasian Cheilanthes and representatives of related cheilanthoid genera. The phylogenetic analysis showed that most Cheilanthes species are related to the genus Hemionitis, constituting different groups according to their distribution; moreover, three species—C. hassleri, C. pantanalensis, and C. obducta—appear as the sister clade of Hemionitis. Cheilanthes micropteris, the type species, is strongly supported in a clade with Australasian Cheilanthes plus five South American Cheilanthes species, all of which show a reduction in the number of spores per sporangium; this feature would be a synapomorphy for core Cheilanthes s.s. We found no support uniting other South American Cheilanthes to either the group of South African Cheilanthes or to core Cheilanthes s.s. On the other hand, C. geraniifolia, C. goyazensis, and C. bradei formed a clade related to Doryopteris that, with further study, could be considered as a new genus. The phylogenetic hypotheses presented here contribute substantially to the delimitation of Cheilanthes s.s. and related groups and provide the basis for re-examining the generic taxonomy. [ABSTRACT FROM AUTHOR]

Common species correspond to most of the structure and biomass of ecosystems, but the determinants of their distributions and the extent of their overlap are still a matter of debate. Here, we tested the hypotheses that (1) common herbaceous and woody species do not respond individualistically to environmental factors, but rather form groups of species with similar environmental affinities (archetypes), and (2) if local communities comprised cohesive systems, then archetypes of common species will occupy distinct portions of the coast with little or no overlap. We used a large set of climatic and soil variables in restinga heath vegetation along ~9000 km of eastern South American coastal plains. We used species archetype models, a new statistical approach that clusters species based on their environmental responses. We found five herbaceous species archetypes and 11 woody species archetypes, all responsive significantly although weakly to a mixture of climatic and soil variables. In most cases, there was considerable spatial overlap of different archetypes rather than separation along the coastline. Common species form groups with similar environmental affinities, but that did not respond strongly to environmental factors. This suggests an important role for dispersal in the explanation of heath vegetation floristic variation. Local community composition is influenced by groups of species that are not unique to any region and overlap extensively. Restinga heath vegetation communities seem to be considerably individualistic rather than cohesive systems. [ABSTRACT FROM AUTHOR]

Cryptantha, an herbaceous plant genus of the Boraginaceae, subtribe Amsinckiinae, has an American amphitropical disjunct distribution, found in western North America and western South America, butnot in the intervening tropics. In a previous study, Cryptantha was found to be polyphyletic and was split into five genera, including a weakly supported, potentially non-monophyletic Cryptantha s. s. In this and subsequent studies of the Amsinckiinae, interrelationships within Cryptantha were generally not strongly supported and sample size was generally low. Here we analyze a greatly increased sampling of Cryptantha taxa using high-throughput, genome skimming data, in which we obtained the complete ribosomal cistron, the nearly complete chloroplast genome, and twenty-three mitochondrial genes. Our analyses have allowed for inference of clades within this complex with strong support. The occurrence of a non-monophyletic Cryptantha is confirmed, with three major clades obtained, termed here the Johnstonella/Albidae clade, the Maritimae clade, and a large Cryptantha core clade, each strongly supported as monophyletic. From these phylogenomic analyses, we assess the classification, character evolution, and phylogeographic history that elucidates the current amphitropical distribution of the group. Revealing the timing, direction, and number of times of dispersal between North and South America gives insight as to the origin of the great biodiversity of these regions. [ABSTRACT FROM AUTHOR]

The Arracacia clade (Apiaceae, Apioideae) is a heterogeneous assemblage of 12 genera, comprising 111 known species distributed in high montane temperate and sub-alpine habitats of meso- and South America. Previous studies have indicated that the genera Arracacia , Coulterophytum , and Prionosciadium are polyphyletic, but for the most part relationships among the members of the clade are largely unknown. Initially, cladistic analyses of nrDNA ITS sequences were carried out on 212 accessions (122 taxa), representing 92 species of the Arracacia clade and outgroups from the closely-related páramo genera Cotopaxia , Niphogeton , and Perissocoeleum and members of the Perennial Endemic North American clade and its allies. Using the ITS results to inform sampling of a small subset of taxa, a pilot study examining the phylogenetic utility of 20 noncoding chloroplast loci was subsequently performed to identify those regions most useful at resolving relationships. A cost-benefit analysis determined that five loci ( trnQ –5′ rps16 , trnD – trnT , rpl32 – trnL , psbD – trnT , ndhA intron) would maximize resolution and branch support in the clade. Cladistic analyses of four of these loci ( trnQ –5′ rps16 , trnD – trnT , rpl32 – trnL , ndhA intron) and the ITS region, separately and combined, revealed that Arracacia , Coaxana , Coulterophytum , Prionosciadium , and Rhodosciadium are each polyphyletic and that Donnellsmithia and Myrrhidendron are each monophyletic. Although most relationships in the Arracacia clade and among the closely-related genera Cotopaxia , Niphogeton , and Perissocoeleum are poorly resolved and supported, ten groups are recognized for future revisionary studies. Polyploidy and rapid species radiation have likely confounded generic circumscriptions and interpretation of relationships. [ABSTRACT FROM AUTHOR]

In the legume genus Senna, series Aphyllae includes seven species of leafless shrubs and subshrubs from arid, semiarid and xerophilous areas of three different biogeographic subregions in southern South America. In this study, we investigated the evolutionary history of Aphyllae in a molecular phylogenetic framework. We reconstructed phylogenetic relationships among Aphyllae species based on DNA sequence data of four plastid ( rpS16, rpL16, matK, trnL-F) and one nuclear (ITS) region from 23 accessions, analyzed with parsimony, Bayesian and maximum likelihood methods. We inferred the evolutionary and biogeographic history estimating divergence times and reconstructing ancestral character states and ancestral areas of distribution. Series Aphyllae was found to be monophyletic, and the taxa formed two main clades: Clade A gathering S. aphylla var. aphylla, S. crassiramea, S. rigidicaulis and S. spiniflora; and Clade B grouping S. acanthoclada, S. aphylla var. divaricata, S. aphylla var. pendula and S. pachyrrhiza. The morphologically complex S. aphylla appears thus polyphyletic. Molecular dating and ancestral area reconstructions suggest that the Aphyllae clade started to diversify in the South American Transition Zone in the Late Pliocene. Based on these results, we hypothesize that this diversification occurred during the last period of Andean uplift with the aridification in South America. The ancestral character state reconstructions suggest that, in addition to the loss of leaves in adult plants, series Aphyllae evolved various morphological features, such as fastigiate, thickened or decumbent-subdecumbent branches during the colonization and establishment in different arid and semiarid lands in South America. [ABSTRACT FROM AUTHOR]

Phytoplasmas in the X-disease group (16SrIII) are highly diverse in terms of geographic distributions, vectorship and plant host specificity. Such biological and ecological diversity is often correlated with distinctive genetic markers present in evolutionarily conserved genes. Based on restriction fragment length polymorphism (RFLP) markers in the 16S rRNA gene sequences, 29 subgroups have been delineated, with most of them being found in the Americas. However, it has been unknown whether distinct geographic lineages are present within a given subgroup. Prior to this study, phytoplasmas belonging to subgroups 16SrIII-J and 16SrIII-U were reported only in countries located in South America. In the present study, we identified new phytoplasmas strains closely related to the reference strains of the two subgroups in Mexico, a North American country. These newly identified Mexican strains possess unique RFLP, single nucleotide polymorphism, and fragmental deletion markers in 16S rRNA- and/or ribosomal protein-encoding genes. Since these markers consistently distinguished the Mexican strains from their South American counterparts, they may represent emerging or previously unknown North American geographic lineages of the subgroups 16SrIII-J and 16SrIII-U. [ABSTRACT FROM AUTHOR]

In the current context of ongoing global change, the understanding of how the niches of invasive species may change between different geographical areas or time periods is extremely important for the early detection and control of future invasions. We evaluated the effect of climate and non-climate variables and the sensitivity to various spatial resolutions (i.e. 1 and 20 km) on niche changes during the invasion of Taraxacum officinale and Ulex europaeus in South America. We estimated niche changes using a combination of principal components analyses ( PCA) and reciprocal Ecological Niche Modelling ( rENM). We further investigated future invasion dynamics under a severe warming scenario for 2050 to unravel the role of niche shifts in the future potential distribution of the species. We observed a clear niche expansion for both species in South America towards higher temperature, precipitation and radiation relative to their native ranges. In contrast, the set of environmental conditions only occupied in the native ranges (i.e. niche unfilling) were less relevant. The magnitude of the niche shifts did not depend on the resolution of the variables. Models calibrated with occurrences from native range predicted large suitable areas in South America (outside of the Andes range) where T. officinale and U. europaeus are currently absent. Additionally, both species could increase their potential distributions by 2050, mostly in the southern part of the continent. In addition, the niche unfilling suggests high potential to invade additional regions in the future, which is extremely relevant considering the current impact of these species in the Southern Hemisphere. These findings confirm that invasive species can occupy new niches that are not predictable from knowledge based only on climate variables or information from the native range. [ABSTRACT FROM AUTHOR]

A list of eight species belonging to Marchantiophyta (Ricciaceae) and ten species to Anthocerotophyta (Anthocerotaceae, Dendrocerotaceae, Notothyladaceae and Phymatocerotaceae) collected in several provinces of Argentina is presented. Five species are new records for the Argentinian bryophyte flora: Riccia limicola, R. weinionis, Anthoceros macounii, A. venosus and Phaeoceros microsporous. Riccia paranaensis and Ricciocarpos natans, collected in Corrientes are new reports from this province; Riccia lamellosa and R. squamata are new records from La Pampa, R. lindmanii from Misiones and Nothoceros endiviifolius from Salta. Four species are second national and provincial records: Riccia australis from Misiones, Phymathoceros bulbiculosus from Corrientes, Phaeomegaceros squamuliger from Neuquén, and Anthoceros lamellatus in Tucumán. For each species, ecology and distribution data for Argentina and South America are given. [ABSTRACT FROM AUTHOR]

In the course of a revision of the New World Ebenaceae for "Flora Neotropica" and some regional floras, specimens from ca. 100 herbaria have been studied. The South American Diospyros sericea A.DC. (synonyms: D. vestita Benoist, and D. praetermissa Sandwith), and D. pseudoxylopia Mildbr. are here described in detail. Lectotypes for these four taxa are selected. Figures, distribution maps, vernacular names, information on habitat and ecology, lists of specimens, and an identification key are included. [ABSTRACT FROM AUTHOR]

Cephaloziella hampeana (Nees) Schiffn. ex Loeske is recorded for the first time in South America. This record considerably extends the distributional range of C. hampeana and raises the question on the role that high mountain environments play in dispersing species along the continent. The morphological differences of C. hampeana with its purportedly allied species are discussed. Additionally, its disjunct distributional pattern is briefly compared with those of other liverworts. Photomicrographs and a distributional map are provided. [ABSTRACT FROM AUTHOR]

In spite of recent advances, the relative roles of deterministic and stochastic processes in community assembly remains disputed. We tested community assembly hypotheses in a disturbance gradient in a logged mixed conifer-hardwood forest complex in southern Brazil. If abiotic heterogeneity was strong enough (Selection hypothesis), we expected niche clustering and reduced niche overlap between species and between ecological groups, phylogenetic clustering, significant β-diversity departure from a random expectation after controlling for α-diversity variation, and non-random trait distribution due to abiotic filtering and limiting similarity. Null expectations were predicted under the Neutral hypothesis. Under the Quasi-Neutral hypothesis, we expected niche clustering and reduced niche overlap as in the Selection hypothesis, but random phylogenetic distribution, random β-diversity variation, and random trait distribution due to niche-based specialization but weak habitat matching resulting from dispersal limitation and drift. We used a series of null models to provide an integrative evaluation of community assembly including species abundances, environmental preferences, phylogenetic relatedness, and trait distribution. Results supported the Quasi-Neutral hypothesis due to a combination of reduced niche overlap, niche clustering along soil and disturbance gradients, evidence for abiotic filtering of functional traits but absent phylogenetic structure and random β-diversity variation. Support to the Quasi-Neutral hypothesis provides evidence for niche-based species selection along environmental gradients, coupled with poor matches between species distributions and environmental factors due to stochastic processes. It also highlights the importance of an integrative approach to the evaluation of community patterns indicative of assembly processes. Had only a subset of the approaches used been employed and different conclusions would have been reached: niche overlap and trait distribution analyses would have indicated a stronger role for selection, while phylogenetic and abundance analyses would have indicated stochastic community assembly. Future research should include different disturbance regimes along with environmental variation in order to assess the interplay of the different drivers that shape the community assembly process, as well as the potential of the Quasi-Neutral hypothesis as an explanation for the assembly process of complex and species-rich subtropical forests. [ABSTRACT FROM AUTHOR]

Azorella is a genus with 26 species of Azorelloideae (Apiaceae) that grow from Costa Rica to the subantartic islands, being distintive and dominant in different environments of the Andean Cordilleras from Venezuela to Patagonia. The species of Azorella that grow in Argentina have been revised taxonomically in a previous study. However, knowledge of the remaining species is fragmentary and uneven. The aim of this paper is to update and standardize the information of the 11 species of Azorella absent in Argentina and present in Bolivia, Chile, Colombia, Ecuador, Peru and/or Venezuela. We provide descriptions for those species and update distributional maps, and we solve nomenclatural and typification problems for 41 names, designating 2 type species, 16 lectotypes and 1 neotype. In addition, we provide 10 new illustrations, and an identification key for all the species of the genus. [ABSTRACT FROM AUTHOR]

Aim Past climatic and geological events can be used to interpret present distributions of organisms. We use chronological and spatial analyses of the species of Myrceugenia in southern South America to help explain their present distribution. Location Southern South America (Argentina, Brazil, Chile, Paraguay and Uruguay). Methods Chronological analyses were completed for the tribe Myrteae (Myrtaceae) using two nuclear DNA sequences and for the genus Myrceugenia using four chloroplast and two nuclear sequences. A biogeographical analysis of Myrceugenia was carried out. Based on calibration points from fossils and estimations, a relaxed molecular clock was used to estimate divergence times and rates of speciation within each lineage. Ancestral states were reconstructed through Bayesian analysis. Results The chronogram implies that tribe Myrteae diversified at the end of the Cretaceous, but that the majority of the individual lineages originated more recently . Myrceugenia diverged into four lineages during the early Miocene. Three of these lineages diversified in Chile, with dispersal to the north and south of the country plus a recent dispersal to the Juan Fernández archipelago. The fourth lineage diversified through vicariant events in south-eastern Brazil. The ancestors of Blepharocalyx, Myrceugenia fernandeziana and Luma are very ancient lineages that originated between the Palaeocene and Eocene, and which have remained stable with little or no subsequent diversification. Main conclusions The estimated age for diversification of tribe Myrteae is consistent with the known fossil evidence from southern South America. The distribution of Myrceugenia may be explained by a combination of three events occurring in the early-middle Miocene: uplift of the Andes, a rain-shadow effect and a marine transgression. These events may also have led to disjunct distributions in several other genera in southern South America. [ABSTRACT FROM AUTHOR]

The Pilosocereus aurisetus complex consists of eight cactus species with a fragmented distribution associated to xeric enclaves within the Cerrado biome in eastern South America. The phylogeny of these species is incompletely resolved, and this instability complicates evolutionary analyses. Previous analyses based on both plastid and microsatellite markers suggested that this complex contained species with inherent phylogeographic structure, which was attributed to recent diversification and recurring range shifts. However, limitations of the molecular markers used in these analyses prevented some questions from being properly addressed. In order to better understand the relationship among these species and make a preliminary assessment of the genetic structure within them, we developed anonymous nuclear loci from pyrosequencing data of 40 individuals from four species in the P. aurisetus complex. The data obtained from these loci were used to identify genetic clusters within species, and to investigate the phylogenetic relationship among these inferred clusters using a species tree methodology. Coupled with a palaeodistributional modelling, our results reveal a deep phylogenetic and climatic disjunction between two geographic lineages. Our results highlight the importance of sampling more regions from the genome to gain better insights on the evolution of species with an intricate evolutionary history. The methodology used here provides a feasible approach to develop numerous genealogical molecular markers throughout the genome for non-model species. These data provide a more robust hypothesis for the relationship among the lineages of the P. aurisetus complex. [ABSTRACT FROM AUTHOR]

Gentiana species and varieties in the Andes of South America are morphologically weakly differentiated and geographical distribution ranges are not known. Here, we recorded 20 morphological characters for 135 individuals of Gentiana from within and outside South America, and observed four additional characters from a large collection of georeferenced flower photographs. To assess geographical patterns and draw taxonomic consequences, the characters were evaluated individually using box plots and histograms, and together using multivariate ordination plots. Our data support the recognition of two species: one in northern South America, G. sedifolia Kunth, and one in southern South America, G. gayi Griseb., which seem to intergrade in southern Bolivia approximately where wet puna converges into dry puna vegetation. Unusually small individuals of the southern lineage occur in the very South (>45°S). We treat them as G. gayi subsp. magellanica (Kusn.) S.Pfanzelt et K.B.Hagen comb. et stat. nov. We found no support for other previously described species or varieties and if they exist they will be of local distribution only. The respective lectotypifications are made. In our preferred scenario, G. sedifolia and G. gayi have colonized South America independently from the northern hemisphere, although this was not unequivocal and both species are closely related. [ABSTRACT FROM AUTHOR]

The article focuses on the revision to the taxonomy of the South American species of Hypolepis (Dennstaedtiaceae). It discusses the plant terrestrial, distribution, and ecology of several Hypolepis species including Hypolepis parallelogramma of Peru, Hypolepis paulistana of São Paulo, Brazil, and Hypolepis pedropaloensis of Colombia. Other species mentioned are Hypolepis poeppigii, Hypolepis pteroides, and Hypolepis rigescens.

The biogeographic history of southern South America has led to a markedly distinct flora within the frame of the Neotropics, which is also particularly heterogeneous in terms of its eco-geographic distribution. This environmental complexity is at the base of the many and controversial classification systems that have been proposed for the vegetation of the so-called Cono Sur region (Paraguay, Chile, Argentina, Uruguay and parts of Brazil and Bolivia). In this study, we aimed to assess the floristic consistency of the main vegetation types that inhabit the region. Our dataset consisted of 116,130 occurrence records of 3662 species of shrubs and trees in 781 sampling sites spread over six countries and eight phytogeographic domains: Atlantic Forest, Pampa, Gran Chaco, Patagonia, Southern Andean, Mediterranean Chile, Temperate Pacific, and Pacific Islands. We performed a cluster analysis and nonmetric multidimensional scaling ordination analysis of this dataset followed by multi-response permutation procedures and permutational multivariate analysis of variance and taxonomic distinction index and indicator species. The greater differentiation took place among the phytogeographic domains and leaf flush regimes (evergreen, deciduous, and semideciduous) though there was also a remarkable latitudinal gradient. Our analyses showed that the pre-defined vegetation types were consistent in terms of woody flora composition and have a considerable number of indicators, many of which endemic. In terms of conservation prioritization, Atlantic Rain Forest therefore has importance because of its high species richness while temperate and mediterranean forests west of the Andes should not be ignored given that they show much higher endemism than would be expected given their species richness. [ABSTRACT FROM AUTHOR]

Selaginella boomii is described as a new species and compared to the similar S. roraimensis. The new species is widely distributed in Venezuela, Guyana, Suriname, and Brazil where it grows on granite outcrops and boulders in forests and savannas. Selaginella boomii is illustrated with Scanning Electron Micrographs of stem sections, leaves, and spores, and its conservation status is discussed based on IUCN Categories and Criteria. This new species is classified within subgenus Stachygynandrum because of its heteromorphic vegetative leaves and monomorphic sporophylls that are arranged in quadrangular strobili. Finally, a brief overview on the current number of Selaginella species known from South America is provided to highlight that our knowledge of the diversity of this genus in the region is far from complete. [ABSTRACT FROM AUTHOR]

* Premise of the study: The Tetramerium lineage (Acanthaceae) presents a striking ecological structuring in South America, with groups concentrated in moist forests or in seasonally dry forests. In this study, we investigate the circumscription and relationships of the South American genera as a basis for better understanding historic interactions between dry and moist biomes in the Neotropics. * Methods: We dated the ancestral distribution of the Tetramerium lineage based on one nuclear and four plastid DNA regions. Maximum parsimony, maximum likelihood, and Bayesian inference analyses were performed for this study using 104 terminals. Phylogenetic divergences were dated using a relaxed molecular clock approach and ancestral distributions obtained from dispersal-vicariance analyses. * Key results: The genera Pachystachys, Schaueria, and Thyrsacanthus are nonmonophyletic. A dry forest lineage dispersed from North America to South America and reached the southwestern part of the continent between the end of the Miocene and beginning of the Pleistocene. This period coincides with the segregation between Amazonian and Atlantic moist forests that established the geographic structure currently found in the group. * Conclusions: The South American genera Pachystachys, Schaueria, and Thyrsacanthus need to be recircumscribed. The congruence among biogeographical events found for the Tetramerium lineage suggests that the dry forest centers currently dispersed throughout South America are relatively old remnants, probably isolated since the Neogene, much earlier than the Last Glacial Maximum postulated by the Pleistocene Arc hypothesis. In addition to exploring the Pleistocene Arc hypothesis, this research also informs evolution in a lineage with numerous geographically restricted and threatened species. [ABSTRACT FROM AUTHOR]

The Paraná River floodplain comprises one of the largest wetland systems of South America. In a sector of the Lower Paraná River floodplain (100 km length, 3650 km 2 ), floristic composition and species diversity was characterized in 88 sites surveyed during summers 2010–11 and 2011–12. Hierarchical and fuzzy classifications were used to construct 26 floristic groups and 8 associations of floristic groups, and their indicator species were identified. A number of 124 species was distributed with a zonation pattern conforming marshes, salt marshes, wet prairies, bunchgrasses, grasslands and scrublands. We assessed how vegetation is affected by four nested levels of environmental constraints, representing a gradient from a landscape to a local scale, and including hydrological, geomorphological, topographic and edaphic variables. Species richness differed within categories of broad-scale landscape units (level 1) and within topographic positions (level 3). Also, 30 plant species, six floristic groups and five associations of groups responded to levels 1–3. The first two axes of a constrained Outlying Mean Index ordination accounted for 60% of the marginality of 61 common species as a function of soil features and flood frequency (level 4). Thus, the distribution of seven species showed significant marginality in association to soil electrical conductivity, soil silt percent and soil total nitrogen concentration. Multi-scale environmental constraints determined vegetation zones, and emerging floristic and diversity patterns. The multi-scale approach significantly improves the understanding of floristic patterns and plant biodiversity in the study area, and may be extended to other floodplain wetlands. [ABSTRACT FROM AUTHOR]

Tweedia is a genus traditionally regarded as composed of seven species distributed on both sides of the Andes in southern South America. Recent molecular analyses of two of its species have shown that they are found in different lineages within the MOOG clade of Apocynaceae subfam. Asclepiadoideae, which questions its monophyly and generic affinities. Whereas Tweedia australis falls within the Diplolepis clade of MOOG, T. brunonis appears within tribe Oxypetalinae. This work provides a molecular phylogeny of all species of Tweedia including its type, T. birostrata, to test the monophyly of the group and assess its relationships with Diplolepis and other genera of the MOOG clade. Phylogenetic analyses of cpDNA trnT-trnF and rps16 regions of 68 accessions of Apocynaceae using maximum parsimony, maximum likelihood, and Bayesian inference methods show that Tweedia species form a well-supported monophyletic group that is morphologically distinct, allied to Araujia and Philibertia of the Oxypetalinae. The study also supports the recent transfer of the former T. australis to Diplolepis as D. australis. Within Tweedia, two clades divided by the Andes can be recognized, one from the west (central Chile) and one from the east (western Argentina). The geographical and environmental characteristics of the genus and of these two groups are discussed in an evolutionary context. [ABSTRACT FROM AUTHOR]

Questions How do climbing species richness and composition change between subtropical and temperate areas of southern South America? How do growth form (lianas and vines) and climbing mechanisms change between subtropical and temperate areas of southern South America? How much of the diversity of species and traits of the extratropical climbing flora is derived from taxa shared with the tropical region? Location Subtropical (23-30° S) and temperate (>30° S) areas of South America. Methods An extensive literature search was carried out in the main databases concerning the flora of southern South America. Climbing species occurrence in subtropical and temperate areas and climbing traits were retrieved. Differences in the frequencies of both growth forms and climbing mechanisms between areas were evaluated using chi-square analyses. Trait frequencies in subtropical and temperate floras were analysed with and without considering species shared with the tropical region. Results Climbing species richness decreased from subtropical to temperate areas, and there were changes in the taxonomic composition. The frequency of growth forms and climbing mechanisms differed between subtropical and temperate areas. Herbaceous vines accounted for 85% of temperate-exclusive species. Twiners contributed less to climber richness in the temperate area, while tendril-bearers and leaf-climbers became more important; root-climbers were only found in temperate forests. Species shared with the tropical region increase the number of liana species in both subtropical and temperate floras, but alter the frequencies of climbing mechanisms in the subtropical flora only. Conclusions Results call for a re-evaluation of the importance that is given to climbers in regions outside the tropics. Vines must be included in models of distribution and abundance of climbers in order to gain a better understanding of climbing plant ecology. The association between climbing mechanisms and the success of climbing plant species in different ecosystems must be further investigated. [ABSTRACT FROM AUTHOR]

Steereella lilliana is reported as a new record for the bryophyte flora in Argentina and South America. Furthermore, the distribution of Frullania brasiliensis in Argentina, previously known only from Misiones and Salta, is expanded to the provinces of Tucumán and Córdoba. Additionally, Stephaniella paraphyllina, is new to the province of San Luis, collected in Sierra de Comechingones, and this represents its southernmost distribution. Brief comments about morphological characters, keys to related species in Argentina, as well as habitat details are given. [ABSTRACT FROM AUTHOR]

Highlights: [•] Distributions with and without the host plants were not different. [•] SVM had low performance when we considered all host plants distributions. [•] MaxEnt and SVM performed similarly while predicting the new L. huberi occurrences. [•] Northeastern, eastern and southeastern South America are indicated for surveys. [Copyright &y& Elsevier]

The statistical analysis of published Paleocene–Late Miocene palynological data from Patagonia supports several major stages of vegetation. These stages represent distinctive floral assemblages, both in composition and structure. Detrended correspondence analysis shows that during the Paleocene, southern South America was dominated by Australasian, Neotropical and Pantropical phytogeographical elements (Gondwanic paleoflora). The climate was warm and very humid. The Early Eocene was dominated by Neotropical and Pantropical taxa (Subtropical Gondwanic Paleoflora) and a reduced proportion of Australasian and a low proportion of Antarctic elements. The Middle Eocene and Oligocene were characterized by the ‘Mixed Paleoflora’ with the exception of the Sloggett Formation. The climate was less humid due to the onset of the Antarctic glaciation. The presence of Antarctic palynomorphs (Nothofagaceae, Podocarpaceae, Proteaceae) in Patagonia is consistent with the global cooling trend during the Late Eocene and Early Oligocene. By the Late Oligocene–Early Miocene, warm climates allowed the southward dispersal of Neotropical elements (palms,Cupania,Alchornea, Rubiaceae, Combretaceae), adding megathermal elements to the local Gondwanic floras. The appearance of some Neotropical families (Symplocaceae, EuphorbiaceaeAlchornea) may indicate the Late Oligocene global warming event. The rise of xerophytic and halophytic shrubby-herbaceous elements (Convolvulaceae, Asteraceae, Poaceae, Chenopodiaceae and Ephedraceae) during the Late Oligocene, becoming more abundant during the Early Miocene began to give a modern appearance to plant communities. The Early–Middle Miocene corresponds to the Transitional Paleophytogeoprovince of central and southeastern Argentina, defined by a mix of Neotropical and Austral components. The Middle–Late Miocene was characterized by the final demise of megathermal elements in Patagonia, coupled with an increasing diversity and abundance of xerophytic adapted taxa, including Asteraceae, Chenopodiaceae and Convolvulaceae. Late Miocene vegetation was similar to the present vegetation, with the steppe expanded across extra-Andean Patagonia and the forest restricted to western areas where rainfall was still abundant. [ABSTRACT FROM PUBLISHER]

Blindia Bruch & Schimp. is represented in southern South America by eight species. Of these, B. buckii B.K. Andreas, B. rigida B.K. Andreas and B. serrata B.K. Andreas, from the Cape Horn Archipelago, are newly described and illustrated herein. Sporophyte descriptions and the sexuality of B. inundata and B. torrentium are reported for the first time. Species descriptions and a key to species from southern South America are presented. [ABSTRACT FROM AUTHOR]

Abstract: Late Quaternary environmental changes, especially sea-level fluctuations and glacial advances and retreats, affected the distribution of the benthic marine fauna which inhabited the Beagle Channel in southernmost South America. To evaluate these changes, calcareous macro-and-microfossils obtained from Holocene marine sediments along a sector of the western side of the Beagle Channel have been used for a multi-proxy approach. In total, 119 species were recovered: 65 mollusks (24 bivalves, 35 gastropods and 6 chitons), 33 foraminifera and 21 ostracods. Other preserved calcareous groups, which appeared in minor proportions, were brachiopods and cirripeds. The calcareous fossil assemblages from the early Holocene represent an ecosystem transition which started with vacant niches first occupied by opportunistic species, and/or eurytopic taxa. These were then replaced by more diverse fauna assemblages, associated with the proliferation of habitats which occurred under truly marine conditions during the Mid Holocene. When Holocene calcareous fauna is compared with its Pleistocene counterparts from the same region, some differences in the proportion of taxonomic groups and taxa composition are noted. These partly follow the heterogeneity of habitats in the Beagle Channel and water masses of different origin which have either greater or less influence throughout the Late Quaternary, but they can also be interpreted in association with environmental changes after the Last Glacial Maximum. In conclusion, the data provide insights into both spatial and temporal changes, and show evidence of a gradual transformation from a brackish to a marine environment caused by the Holocene sea transgression. It also documents Late Quaternary faunistic changes associated with topographic and oceanographic local conditions in this microbasin. [Copyright &y& Elsevier]

Cladistic analyses based on morphology were conducted to test for monophyly, estimate the phylogenetic relationships among the taxa of Chaetolepis, and generate the first comprehensive taxonomic revision of the genus. Prior to this study the genus had included species from Andean South America, the Guayana Highlands, Costa Rica, Cuba, and tropical West Africa. As traditionally delimited, Chaetolepis is not monophyletic because the Cuban species, C. cubensis, is more closely related to outgroup species in the genus Tibouchina. Based on discordant morphological characters such as foliar trichome details and seed morphology, C. cubensis is here treated as a Tibouchina, the genus to which it had been transferred by M. Gómez in 1894. Chaetolepis is treated as a monophyletic genus of 11 species distinguished by 4-merous flowers, isomorphic stamens that lack prominent pedoconnectives and appendages, apically setose 4-locular ovary, capsular fruits, and cochleate seeds. Chaetolepis alpina var. latifolia is relegated to synonymy of C. alpina because it lacks consistent distinguishing characters, and C. thymifolia is synonymized under C. anisandra. The West African monotypic genus, Nerophila gentianoides, is tentatively shown to be congeneric with the Central and South American species of Chaetolepis based on morphology. If molecular data confirms this disposition of N. gentianoides by Jacques-Félix, it will become the only genus of Melastomataceae with a trans-Atlantic distribution. A biogeographical analysis based on the phylogenetic results suggests that Chaetolepis originated in the Colombian Andes and possibly the Sierra Nevada de Santa Marta, with independent dispersal events to Costa Rica, Venezuela, and tropical West Africa. [ABSTRACT FROM AUTHOR]

Eragrostis plana (Poaceae) is a perennial grass introduced from South Africa to the state of Rio Grande do Sul in southern Brazil. Currently, it is considered an invasive grass in several regions of the world, including South America, where it has caused negative ecological and socio-economic impacts. Ecological niche models, using bioclimatic variables, are often used to predict the potential distribution of invasive species. In this study we prepared two bioclimatic models for E. plana using the Genetic Algorithm for Rule-set Production, the first based on data from its native region (South Africa) and the second on data from both the native and invaded (South America) regions. We then projected each model onto South America to identify regions vulnerable to invasion by the species, and compared our results with available records of the species in South America. Finally, we explored the model's predictions for the existence of a bioclimatic niche shift during the invasion process of E. plana in South America, using multivariate statistical analysis. The model created with native distribution data was only able to predict (with highly suitable habitat) the region of introduction of E. plana in South America. However, the current distribution, as well as the region of introduction of the species, was reliably predicted by the model created with data from both native and invaded regions. Our multivariate analysis supports a hypothesis of bioclimatic niche shift during the invasion process of E. plana in South America. [ABSTRACT FROM AUTHOR]

A taxonomic treatment of the genus Diplolepis is here presented. Based on molecular and biogeographical information recently published, this group is monophyletic and its geographical distribution is restricted to southwestern South America. The study comprised the analysis of herbarium specimens including nomenclatural types, supplemented with collections and observation of species in the field. This paper describes the variation in the morphology of the genus, including habit, stems, leaves, inflorescence, calyx, corolla, corona, gynostegium, pollinia, fruits and seeds. The morphological and distributional differences between Diplolepis and related genera are discussed. A key to differentiate the species of the genus is here given. Within each species we provide the valid name, synonyms, description of vegetative and reproductive morphological characters, geographical distribution, ecology, uses, common names, phenology, iconography and specimens examined. A lectotype is designated for D. viridis. [ABSTRACT FROM AUTHOR]

Seeds of Vitaceae and Leeaceae are recognized from the late Early Oligocene of Bele'n, near Talara, northern coastal Peru. Reexamination of fossils described by Berry in the 1920s, supplemented by newly collected specimens, leads us to accept his identifications of Ampelocissus and Cissus. In addition to the two species previously recognized (Ampelocissus bravoi [Berry] Berry and Cissus willardii Berry), the new material allows recognition of another species of Cissus--that is, Cissus lombardii sp. n.--and confirms the presence of Leea, represented by Leea olssonii (Berry) comb. n. These well-preserved fossils show seed characters unequivocally diagnostic for these three extant genera and include two distinct morphotypes of Cissus, indicating that this genus was already diversified in South America by ;28.5 million years ago. The fossils are biogeographically informative because Ampelocissus and Leea are absent from South America today, and the latter is now native only to the Old World tropics. Confirmation of both Vitaceae and Leeaceae from the Oligocene of Peru is significant as an indication that the Vitales were well diversified by this time in South America. [ABSTRACT FROM AUTHOR]

Abstract: Anthurium sect. Urospadix includes approximately 70 species differently distributed in Eastern Brazil, Western South America, and Central America. The present work studied the gynoecia of species of section Urospadix to describe their anatomical features. In all the species studied, the apical portion of the gynoecium differentiates into a stigma covered with short trichomes and an adjacent region formed by isodiametric cells. The stylar canal comprises short, unicellular secretory trichomes extending up to the ovarian aperture. Carpels are apically symplicate and basally synascidiate with a septum that does not reach the apical portion of the locule. The apical portion of the septum differentiates into long, secretory trichomes while the subapical one differentiates into the placenta. Locules are filled with mucilage. Since the epidermis of the region adjacent to the stigma, the length of the stylar portion, and the number of cell layers of the ovarian septum vary among the species studied, they may be useful for further taxonomic and systematic purposes. The present work is the first detailed report of trichome location and distribution on the gynoecia of Anthurium. [Copyright &y& Elsevier]

Guadua tagoara subsp. tagoara is reported for the first time in Argentina, it is described and illustrated. A map showing its geographical distribution in South America and a key to the species and subspecies in Argentina are also provided. A lectotype for Bambusa distorta is here designated. [ABSTRACT FROM AUTHOR]

The new species Sida chiquitana (Cordifoliae), S. parva (Distichifolia), S. cavernicola, S. Glocimari (Malacroidea), S. cabraliana, S. rhizomatosa, S. sucupirana (Muticae), S. japiana and S. Lilianae (Nelavaga) are described. [ABSTRACT FROM AUTHOR]

A transcription and a critical review on Aimé Bonpland´s scarcely known manuscripts dealing with the geographical distribution of wild "yerba mate" (Ilex paraguariensis A. St. Hil., Aquifoliaceae) trees in South America is presented here. Among other data, Bonpland´s assumptions on the occurrence of wild "yerba mate" individuals within present day Uruguayan boundaries are matched with modern voucher specimens of this species collected in Uruguay, and also with miscellaneous bibliographical sources, including details from later reports from Bonpland himself, and also from other contemporary naturalists who travelled through this country in the 1820´s and 1830´s, as well as with phytogeographical information. As a conclusion, it is supposed that these Bonpland´s notes, written during his early years of residence at the Río de La Plata basin, contain mistaken information that the same botanist did not report again, as his knowledge of the Argentinian Delta, the Uruguayan environment and the 'yerba mate" got deeper. [ABSTRACT FROM AUTHOR]

Specimens of Argas monachus Keirans et al. were collected from Myiopsitta monachus nests in 42 localities in Argentina and Paraguay from 2006 to 2010. A list of localities where this tick has been found is presented. 16S rDNA sequences of specimens of A. monachus from different localities were compared to confirm whether they belong to the same specific taxon. Argas monachus is present in the phytogeographic provinces of Chaco, Espinal, and Monte, but not in the Pampa (all from de Chaco Domain) where the host is well distributed. No differences were found among 16S rDNA sequences of geographically distant specimens. [ABSTRACT FROM AUTHOR]

The first collection of the mistletoe Phoradendron argentinum (Viscaceae) for the Brazilian flora is reported. A brief description, a key including the taxonomically closest species, photographs and a distribution map of the species are given. Lectotype of P. argentinum is here designated. [ABSTRACT FROM AUTHOR]

The relationship between the proportion of species with an entire leaf margin (pE) and mean annual temperature (MAT) is one of the most powerful tools for estimating palaeotemperatures. However, phylogenetic and phytogeographic constraints on this relationship have remained unexplored. Here we investigate the pE-MAT relationship for modern floristic assemblages from southern South American forests, assess its conformity to other models and test for the existence of historical constraints on pE-MAT models. South America. We used samples from 30 sites located in Chile between 32° and 44° S to test for a pE-MAT relationship and compared it with four regional models. We assessed the reliability of these models for predicting MAT from instrumental records in eight modern temperate-forest localities in Chile. Additionally, palaeotemperatures for Cenozoic fossil floras were estimated. To assess historical constraints in pE, we measured the phylogenetic signal in leaf margin type and the association between leaf margin and phytogeographic affiliation, defined by the distribution of genera. We found a significant pE-MAT relationship for Chilean forest species that differed from Australia and Northern Hemisphere models, but not from tropical South America (TSA). Temperatures for southern South American localities predicted from the new regional model - combining Chilean and TSA datasets - were more accurate than those from previous models. We also showed that leaf margin type has a strong phylogenetic signal, which was further confirmed by the highly significant effect of phytogeographic element on leaf margin type. Differences between the Chilean and other regional models are explained by historical legacy, as Chilean leaf margin types are strongly affected by phylogenetic closeness and phytogeographic elements. We highlight that leaf margin analyses should be conducted within the context of a flora with a shared history. Thus, we propose a new model for South America to estimate palaeotemperatures for regional fossil floras. [ABSTRACT FROM AUTHOR]

Mentzelia aspera L. is cited for the first time for the Paraguayan flora; this is the first record for the genus Mentzelia and the second for the family Loasaceae from Paraguay. To facilitate identification, a description of the species and some images of diagnostic features are included. [ABSTRACT FROM AUTHOR]