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Alexander von Humboldt's depictions of mountain vegetation are among the most iconic nineteenth century illustrations in the biological sciences. Here we analyse the contemporary context and empirical data for all these depictions, namely the Tableau physique des Andes (1803, 1807), the Geographiae plantarum lineamenta (1815), the Tableau physique des Îles Canaries (1817), and the Esquisse de la Géographie des plantes dans les Andes de Quito (1824/1825). We show that the Tableau physique des Andes does not reflect Humboldt and Bonpland's field data and presents a flawed depiction of plant occurrences and vertical succession of vegetation belts, arising from Humboldt's misreading of La Condamine's description (1751). Humboldt's 1815 depiction, by contrast, shows a distribution of high-vegetation belts that is consistent with La Condamine's description, while the 1824 depiction drops innovations made in 1815 and returns to simply showing numerous species' names, thus not applying Humboldt's own earlier zonation framework. Our analysis of contemporary reactions to Humboldt's TPA includes Francis Hall's posthumously published 1834 illustration of Andean plant zonation near Quito and Humboldt's reaction to Hall's critique. Throughout his work on plant geography, Humboldt disregarded some of his own observations, or confused them. At stake was his reputation as an innovator in the field of plant geography and a discoverer of the sequence of high-elevation vegetation belts on the world's mountains. [ABSTRACT FROM AUTHOR]

The Neotropical Region (NR) is one of the areas with the most plant diversity globally, and its richness of vascular epiphyte (VE) species is higher than Africa and Asia combined. This richness is a consequence of the heterogeneous climate and geological history of the region, both factors also being responsible for the plant distribution patterns. Here, we aimed to explore the phytogeographic relationships of the VE in the NR using 14,636 identified records from 173 surveys exclusively of VE, carried out in 14 countries and 23 biogeographic provinces, comprising 3849 identified species. We assessed the floristic patterns and relationships with climatic variables by multivariate analysis (cluster and ordination analyses). The clustering formed 13 main groups, partly corresponding to the biogeographic units of the NR. Our results demonstrate consistent floristic patterns confirmed through the analysis of floristic similarity, corroborating previous biogeographic classifications in well-studied areas, while broader patterns were found in poorly studied areas. We found a floristic gradient pattern, which allowed us to understand the relationships between environmental conditions and floristic patterns. Furthermore, we discuss our results under the light of the history that likely shaped the current distribution patterns and richness of the VE in the NR. The VE proved to be an important model for testing biogeographic classifications. We encourage the studies of this synusia in the several geographical gaps that remain in the NR, which undoubtedly will improve further studies and support conservationist policies. [ABSTRACT FROM AUTHOR]

Aim: Climate change is expected to impact mountain biodiversity by shifting species ranges and the biomes they shape. The extent and regional variation in these impacts are still poorly understood, particularly in the highly biodiverse Andes. Regional syntheses of climate change impacts on vegetation are pivotal to identify and guide research priorities. Here we review current data, knowledge and uncertainties in past, present and future climate change impacts on vegetation in the Andes. Location: Andes. Taxon: Plants. Methods: We (i) conducted a literature review on Andean vegetation responses to past and contemporary climatic change, (ii) analysed future climate projections for different elevations and slope orientations at 19 Andean locations using an ensemble of model outputs from the Coupled Model Intercomparison Project 5, and (iii) calculated changes in the suitable climate envelope area of Andean biomes and compared these results to studies that used species distribution models. Results: Future climatic changes (2040–2070) are projected to be stronger at high‐elevation areas in the tropical Andes (up to 4°C under RCP 8.5), while in the temperate Andes temperature increases are projected to be up to 2°C. Under this worst‐case scenario, temperate deciduous forests and the grasslands/steppes from the Central and Southern Andes are predicted to show the greatest losses of suitable climatic space (30% and 17%–23%, respectively). The high vulnerability of these biomes contrasts with the low attention from researchers modelling Andean species distributions. Critical knowledge gaps include a lack of an Andean wide plant checklist, insufficient density of weather stations at high‐elevation areas, a lack of high‐resolution climatologies that accommodates the Andes' complex topography and climatic processes, insufficient data to model demographic and ecological processes, and low use of palaeo data for distribution modelling. Main conclusions: Climate change is likely to profoundly affect the extent and composition of Andean biomes. Temperate Andean biomes in particular are susceptible to substantial area contractions. There are, however, considerable challenges and uncertainties in modelling species and biome responses and a pressing need for a region‐wide approach to address knowledge gaps and improve understanding and monitoring of climate change impacts in these globally important biomes. [ABSTRACT FROM AUTHOR]

Global warming, coupled with habitat destruction and human activity, are accelerating the rates of species extinction worldwide. Species-extinction risk assessment using the IUCN Red List categories, together with the study of the spatial patterns of biodiversity, are fundamental approaches for identifying conservation priorities and targeting government decisions to mitigate impacts on biodiversity. Here, we analyzed the geographic distribution of Argentinean species of Brassicaceae using species point distributional data. In this way, we classified species following the IUCN threat categories at a regional level, and analyzed patterns of richness, endemism, and threat on the different ecoregions and biomes of the country. In addition, we also explored differences in elevation, annual mean temperature, annual precipitation, and aridity between endemic vs. non-endemic and threatened vs. non-threatened species. The results showed that of the 162 Argentinean taxa, 58 species were here categorized as threatened (VU, EN, or CR) (36%). However, when only endemics are considered, more than half of these (33 spp, 57%) are threatened. Although species inhabit all environments and biogeographic regions of the country, arid to semi-arid areas, which are associated to the Andes and the Patagonian steppe, contained most of the species. Specifically, the Central Andean Puna and the Patagonian steppe ecoregions included the greatest number of species, endemics, and threatened species. Furthermore, different hotspots of richness, endemism, and threat were detected along Andean regions and the Patagonian steppe, and endemics were characterized by inhabiting on average drier areas than non-endemic native species. An up-to-date species list, including conservation status, distribution maps for all species, hotspots of richness, endemism, and threat, are also provided. This work seeks to contribute to the knowledge on geographical patterns of the Argentinean flora and its conservation, complementing the information published in the Flora of Argentina. [ABSTRACT FROM AUTHOR]

Dispersal, physical conditions and biotic interactions contribute to determine the spatial distribution of individuals in plant populations. Much of what we know has been learned from studies that retrospectively posit mechanisms presumed to have generated the observed spatial patterns. Here we present a prospective approach. We start by measuring spatial demographic effects and evaluate if they can generate observed spatial patterns. We evaluated the influence of interactions among conspecifics on vital rates, demography and spatial distribution of Croton aff. wagneri, a dominant shrub in dry Andean ecosystems. Recruitment, survival and growth varied in relation with distance to conspecifics neighbours and with their summed cover. We built a spatial individual‐based model and simulated its population dynamics in 30 × 30 m plots for a 30‐year period. We compared the predicted spatial pattern from these demographic models with that observed among plants in 16 independent plots with the same area. Simulated populations mimicked observed spatial patterns, although in plots at high elevations the simulated populations did not reproduce the observed inhibition at small scales. Observed and simulated patterns indicated differences between elevations in maximum aggregation and location of the distances with higher aggregation. We discuss how consideration of critical seed and juvenile stages and interspecific interactions could further improve our understanding of spatial pattern and recommend that these factors be considered in future models. We developed a prospective approach to evaluate the influence of interactions among conspecifics on vital rates, demography and spatial distribution of Croton aff. wagneri, a dominant shrub in dry Andean ecosystems. We built a spatial individual‐based model and simulated its population dynamics to compare predicted spatial pattern from demographic models with that observed among plants in 16 independent plots. Simulated populations mimicked observed spatial patterns, although in plots at high elevations the simulated populations did not reproduce the observed inhibition at small scales. [ABSTRACT FROM AUTHOR]

Riccardia is a large genus of thalloid liverworts and notoriously difficult in terms of species recognition. Thirty six species were recognized in the tropical Andes but many of these are not well-defined. In this paper fourteen species are accepted for Colombia and Ecuador; eighteen species and two varieties are reduced to synonymy. Descriptions and illustrations are provided for the accepted species together with a key and data on types, synonymy, geographical distribution, habitat and differentiating characters. Riccardia palmata and R. multifida are excluded from the flora of Colombia and Ecuador. The new combination Riccardia latifrons subsp. parasitans (Steph.) Gradst. & Reeb comb. nov. is proposed and eighteen new lectotypifications are made. [ABSTRACT FROM AUTHOR]

Background The páramo is a high-elevation biogeographical province in the northern Andes, known for its great biodiversity and ecosystem services. Because there have been very few biogeographic studies encompassing the entire province to date, this study aimed at conducting a phytogeographical regionalisation of the páramo. Specifically, (1) clustering analyses were conducted to identify the main phytogeographical units in the three altitudinal belts: sub-páramo, mid-páramo and super-páramo, and examine their diagnostic flora, (2) an ordination complemented the geo-climatic characterization of the obtained units and (3) a hierarchical classification transformation was obtained to evaluate the relationships between units. Methods The study area included the entire Andean páramo range in northern Peru, Ecuador, Colombia and Venezuela. The analyses were based on 1,647 phytosociological plots from the VegPáramo database. The K-means non-hierarchical clustering technique was used to obtain clusters identifiable as phytogeographical units, and the Ochiai fidelity index was calculated to identify their diagnostic species. A principal component analysis was conducted to obtain the geo-climatic characterization of each unit. Finally, the relationships between clusters were traced using a hierarchical plot-based classification. Results Fifteen clusters were obtained, 13 natural and two artificial, of which two represented the sub-páramo, nine the mid-páramo and four the super-páramo. Even though data representativeness was a potential limitation to segregate certain sub-páramo and super-páramo units, the overall bioregionalisation was robust and represented important latitudinal, altitudinal and climatic gradients. Discussion This study is the first to bioregionalise the páramo province based on a substantial widely distributed biological dataset, and therefore provides important novel scientific insight on its biogeography. The obtained phytogeographical units can be used to support further research on the páramo at smaller scale and on the humid Neotropical high-elevation ecosystems at broader-scale. Finally, several units were highlighted in our results as particularly worthy of further scientific and conservation focus.

A recent phylogenomic study has shown that Diplostephium in its broad sense is biphyletic. While one of the clades comprises 60 species distributed mainly in the Northern Andes, the clade that contains the generic type, Diplostephium ericoides, contains 48 species, and primarily inhabits the Central Andes. Here, I propose to reinstate the generic name Piofontia and transfer to it the species of Diplostephium in the Northern Andean clade. Piofontia consists, then, of 60 species of woody subshrubs, shrubs, and small trees inhabiting high Andean forests and páramos of Costa Rica, Colombia, Venezuela, and Ecuador. A morphological description is provided for the genus Piofontia along with a species list with 60 new combinations. Dysaster cajamarcensis is shown to be a synonym of Diplostephium serratifolium. Finally, a brief discussion about themorphological evolution of South American Astereae is provided. [ABSTRACT FROM AUTHOR]

Background: The páramo is a high-elevation biogeographical province in the northern Andes, known for its great biodiversity and ecosystem services. Because there have been very few biogeographic studies encompassing the entire province to date, this study aimed at conducting a phytogeographical regionalisation of the páramo. Specifically, (1) clustering analyses were conducted to identify the main phytogeographical units in the three altitudinal belts: sub-páramo, mid-páramo and super-páramo, and examine their diagnostic flora, (2) an ordination complemented the geo-climatic characterization of the obtained units and (3) a hierarchical classification transformation was obtained to evaluate the relationships between units. Methods: The study area included the entire Andean páramo range in northern Peru, Ecuador, Colombia and Venezuela. The analyses were based on 1,647 phytosociological plots from the VegPáramo database. The K-means nonhierarchical clustering technique was used to obtain clusters identifiable as phytogeographical units, and the Ochiai fidelity index was calculated to identify their diagnostic species. A principal component analysis was conducted to obtain the geo-climatic characterization of each unit. Finally, the relationships between clusters were traced using a hierarchical plot-based classification. Results: Fifteen clusters were obtained, 13 natural and two artificial, of which two represented the sub-páramo, nine the mid-páramo and four the super-páramo. Even though data representativeness was a potential limitation to segregate certain subpáramo and super-páramo units, the overall bioregionalisation was robust and represented important latitudinal, altitudinal and climatic gradients. Discussion: This study is the first to bioregionalise the páramo province based on a substantial widely distributed biological dataset, and therefore provides important novel scientific insight on its biogeography. The obtained phytogeographical units can be used to support further research on the páramo at smaller scale and on the humid Neotropical high-elevation ecosystems at broader-scale. Finally, several units were highlighted in our results as particularly worthy of further scientific and conservation focus. [ABSTRACT FROM AUTHOR]

Tetraglochin is distributed along the Andes from Peru to southern Argentina and central Chile. In order to test its monophyly and analyze relationships among species of this genus and allied genera, we conducted morphological studies and phylogenetic analyses using both nuclear (ITS) and cpDNA ( trnL-F) sequences. As a result, Tetraglochin is supported as monophyletic, with the genus Margyricarpus as its sister group. Tetraglochin acanthocarpa and T. caespitosa are sister to the rest of the genus, which is grouped in two clades. One clade grows primarily distributed along the Central Andes, includes T. cristata, T. inermis, plus some specimens of T. ameghinoi, and has a coriaceous or papery and non translucent hypanthium. The other clade is mainly in the Southern Andes, contains T. alata and some specimens of T. ameghinoi, and has a membranous translucent hypanthium. Based on results obtained from morphological studies, molecular phylogenies, and species delimitation analyses, a new species T. andina, is proposed, segregated from T. ameghinoi. A key to identify all species herein recognized, and a map containing geographical distribution of them are provided, together with a description and illustration of the new species. [ABSTRACT FROM AUTHOR]

Three species of the genus Cyathea from the sandstone areas of the Amotape-Huancabamba zone are described as new to science: Cyathea abrapatriciana and C. oreopteroides from northern Peru and C. chimaera from southern Ecuador. They are illustrated and discussed regarding their biogeography and putative relationships. [ABSTRACT FROM AUTHOR]

We propose a new classification for the South American species of the genus Bartsia L. and relatives recently included in an expanded treatment of the genus Bellardia (L.) All. This new classification reflects their evolutionary history, and is based on morphological and molecular evidence, biogeographic hypotheses, and rates of diversification for these species. Additionally, we rearranged the current taxonomic classification of close relatives so that the current circumscriptions encompass only monophyletic groups. Some of these changes include the creation of a new genus, Neobartsia Uribe-Convers and Tank (47 spp.), as well as the reclassification of Bellardia latifolia (L.) Cuatrec. back to Parentucellia latifolia (L.) Caruel. These taxonomic changes are important for proper communication within the large Rhinantheae clade of Orobanchaceae, and for the interpretation of biogeographic patterns and diversification processes of these species. [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 Morelloid clade of Solanum, also known as the black nightshades or Maurella (Morelia), is one of the 10 major clades within Solanum. The pantropical clade consists of ca. 76 non-spiny herbaceous and suffrutescent species with simple or branched hairs with or without glandular tips, with a centre of distribution in the tropical Andes. Although the core members of the clade have long been recognised, complete circumscription of the Morelloid clade has remained elusive. Here we provide the first detailed molecular study of the clade. Plastid (trnT-F intergenic spacers), nuclear ribosomal ITS, and low-copy nuclear (waxy) data show three of the four previously unplaced taxa loosely associated with the Morelloids to be placed outside (S. anomalostemon, S. valdiviense, S. reductum), whilst S. salicifolium, a species previously associated with the Dulcamaroid clade, is found to be nested within the group. Four monophyletic groups within the Morelloids can be recognised: (1) Black nightshade clade, including all members of 5. sect. Solanum, S. sect. Campanulisolanum, branched-haired taxa, S. salicifolium, and S. triflorum; (2) Episarcophyllum clade, including most members of S. sect. Episarcophyllum; (3) Chamaesarachidium clade, including members of S. sect. Chamaesarachidium; and (4) Radicans clade, including four species from S. sect. Parasolanum. Incongruence between nuclear and plastid gene trees is discussed in relation to known ploidy level variation across the Morelloid clade, especially the African species often referred to as the S. nigrum complex. A new, revised circumscription of the Morelloid clade is provided together with morphological characterisations of the monophyletic clades recovered within it. A preliminary checklist of accepted names for Morelloids is also presented. [ABSTRACT FROM AUTHOR]

The current geographical distribution of the rheophytic moss Bucklandiella lamprocarpa (Müll.Hal.) Bednarek-Ochyra et Ochyra in the central and northern Andean countries in South America is reviewed and mapped. The specimens reported from Peru as Racomitrium bartramii (Roiv.) H.Rob. are taxonomically assessed and some details of their structure are illustrated. As a result of this study it was determined that its morphological features fall well within the range of variability of Bucklandiella lamprocarpa. The global geographical distribution of B. lamprocarpa is outlined and the species is confirmed to be an austral cool-adapted moss which deeply penetrates into the tropics, occurring at high elevations in central and northern South America and in East and Central Africa. [ABSTRACT FROM AUTHOR]

Seven new species of the subtribe Goodyerinae, six ofMicrochilusand one ofAspidogyne, are described and illustrated based on Colombian material. The information about the distribution and ecology of the new entities as well as brief taxonomic notes are provided. [ABSTRACT FROM AUTHOR]