Morphometric analyses and new taxonomic circumscription of South American species of Flourensia (Asteraceae, Heliantheae, Enceliinae)

Flourensia (Asteraceae, Heliantheae, Enceliinae) is an amphitropical genus of resinous subshrubs, shrubs and small trees with 13 North American and 20 South American species among which disagreement on the species limits of some members still exists. To resolve the taxonomy of the South American taxa, we carried out a combination of clustering (Ward's method with Gower distance coefficient) and ordination analyses (Principal Coordinate Analyses) based on 34 vegetative and reproductive characters scored from herbarium material, including types. Based on the results, we recognize 12 South American species: F. angustifolia, F. cajabambensis, F. fiebrigii, F. heterolepis, F. hirtissima, F. macrophylla, F. niederleinii; F. peruviana, F. polycephala, F. thurifera, F. tortuosa and F. suffrutescens. A number of species are placed in synonymy: Flourensia blakeana and F. hirta are synonymized under the name F. fiebrigii; Flourensia campestris, F. leptopoda, F. oolepis and F. riparia are synonymized under F. thurifera; Flourensia macroligulata is synonymized under F. tortuosa, and Flourensia polyclada is synonymized under F. suffrutescens. A taxonomic treatment of four redefined species as well as a key and distribution maps to all South American Flourensia species are provided.Fil: Ospina Gonzalez, Juan Camilo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Ariza Espinar, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Freire, Susana Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Foliar anatomy and micromorphology of southern South American Alstroemeriaceae: Alstroemerieae, and its systematic implications in Alstroemeria

Alstroemerieae is an exclusively Central and South American tribe belonging to Alstroemeriaceae, which comprises two large genera, Alstroemeria and Bomarea. Alstroemeria has two areas of distribution, mediterranean Chile and central southeastern Brazil. Most Bomarea species grow in forests and hedges in moist areas, however, some species are adapted to dry Andean valleys and high altitudes. Previous leaf anatomical data were obtained from a limited group of species. To assess the value of the anatomical characters for the systematics and their importance as adaptations to different environments, we compared representative species from different geographical areas and habitats. Data regarding leaf anatomy and micromorphology were obtained from light microscopy and scanning electron microscopy and were combined with macromorphology for 27 Alstroemerieae species. In accordance with earlier studies, our results show variation in relation to several leaf morpho-anatomical characters. Based on these we define seven types. We furthermore analyzed the morpho-anatomical characters in a phylogenetic context. Morpho-anatomical characters are highly homoplastic within the family. Leaf anatomy may support monophyly of Baker's informal grouping of Alstroemeria Brazilian species with rigid leaves, however, a more thorough study of Brazilian Alstroemeria species are needed to confirm this.Laboratorio de Etnobotánica y Botánica Aplicad

Evolution of pollination by frugivorous birds in Neotropical Myrtaceae

Bird pollination is relatively common in the tropics, and especially in the Americas. In the predominantly Neotropical tribe Myrteae (Myrtaceae), species of two genera, Acca and Myrrhinium, offer fleshy, sugary petals to the consumption of birds that otherwise eat fruits, thus pollinating the plants in an unusual plant-animal interaction. The phylogenetic position of these genera has been problematic, and therefore, so was the understanding of the evolution of this interaction. Here we include new sequences of Myrrhinium atropurpureum in a comprehensive molecular phylogeny based on a balanced sample of two plastid and two nuclear markers, with the aim of providing the historical framework of pollination by frugivorous birds in Myrteae. We developed 13 flower and inflorescence characters that comprehensively depict the macroscopic morphological components of this interaction. Bayesian and parsimony phylogenies concur in placing both Acca and Myrrhinium in a clade with Psidium species; with Myrrhinium sister to Psidium. Mapping of morphological characters indicated some degree of convergence (e.g., fleshy petals, purplish display) but also considerable divergence in key characters that point to rather opposing pollination strategies and also different degrees of specialization in Acca versus Myrrhinium. Pollination by frugivorous birds represents a special case of mutualism that highlights the evolutionary complexities of plant-animal interactions.Fil: Nadra, Maria Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Giannini, Norberto Pedro. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Acosta, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Rarity patterns and conservation priorities in Cactaceae species from the Southern Central Andes: a case study from the Calchaquíes Valleys, Salta, Argentina

En este trabajo se estudiaron 34 especies de Cactaceae de los Valles Calchaquíes, Argentina, para determinar 1) el nivel de rareza de las especies, 2) la proporción de especies raras entre grupos taxonómicos y ecológicos, y 3) la consistencia espacial de la rareza a lo largo del rango de distribución. Se definió a la rareza a través de un modelo que combina medidas del rango geográfico de distribución y el tamaño poblacional local de cada especie. La rareza no se concentró en ningún grupo taxonómico o ecológico particular de Cactaceae; sin embargo, 28 especies presentaron algún nivel de rareza. En la mayoría de las especies, la rareza varió a lo largo del área de distribución geográfica; sólo cinco especies fueron consistentemente raras en todas las poblaciones evaluadas. Seis especies fueron calificadas como extremadamente raras; todas de la subfamilia Cactoideae, cuatro endémicas del sur de los Andes Centrales y difiriendo en su forma de crecimiento. Sólo dos de las 34 especies estudiadas presentaron una rareza extrema y constante a lo largo de toda su distribución. La determinación del nivel de rareza fue útil para identificar especies que pueden estar en peligro o que pueden necesitar más estudios. Este trabajo permitió indicar qué especies de Cactaceae son más vulnerables a las perturbaciones antropogénicas o naturales, en comparación con las especies comunes. Muchas de las especies Cactaceae identificadas aquí como raras fueron mencionados por la IUCN en las categorías intermedias de extinción, por lo que la rareza parece estar relacionada con la vulnerabilidad a la extinción en la parte más sur de los Andes Centrales.In this study, 34 Cactaceae species from the Calchaquíes Valleys, Argentina, were studied to determine 1) species rarity level, 2) proportion of rare species among taxonomic and ecological groups and, 3) whether rareness is consistently distributed throughout the species geographical ranges. We used a model where rarity is defined by the geographic range and the local population size to define species rarity. Rareness was not concentrated in any particular taxonomic or ecological group of Cactaceae; however 28 species were rare at some level. In most species, rarity varied across the geographical range, only five species remained consistently rare in all the surveyed populations. Six species qualified as extremely rare, all from the Cactoideae subfamily, four endemic to the southernmost Central Andes and differing in their growth forms. Only two of the 34 studied species, appeared as both extremely and consistently rare across its distribution. Determining rarity levels is useful for identifying species that may be in danger and/or in need for further studies. Rarity, used as an indicator of species vulnerability, allowed us, to identify Cactaceae species that are more vulnerable to anthropogenic or natural disturbance, compared with common species. Many of the Cactaceae species identified here as rare were mentioned by IUCN at intermediate categories of extinction. Our approach seems then to yield useful results and rareness in the present context appears to be related with vulnerability to extinction within the southernmost Central Andes.Fil: Godoy Bürki, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Sajama, Modesto Jesus. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Escuela de Agronomía. Laboratorio de Investigaciones Botánicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bravo, Silvia Alejandra. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Escuela de Agronomía. Laboratorio de Investigaciones Botánicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alonso Pedano, Mariana Inés. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Escuela de Agronomía. Laboratorio de Investigaciones Botánicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ortega Baes, Francisco Pablo. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Escuela de Agronomía. Laboratorio de Investigaciones Botánicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Macro-Climatic Distribution Limits Show Both Niche Expansion and Niche Specialization among C4 Panicoids

Grasses are ancestrally tropical understory species whose current dominance in warm open habitats is linked to the evolution of C4 photosynthesis. C4 grasses maintain high rates of photosynthesis in warm and water stressed environments, and the syndrome is considered to induce niche shifts into these habitats while adaptation to cold ones may be compromised. Global biogeographic analyses of C4 grasses have, however, concentrated on diversity patterns, while paying little attention to distributional limits. Using phylogenetic contrast analyses, we compared macro-climatic distribution limits among ~1300 grasses from the subfamily Panicoideae, which includes 4/5 of the known photosynthetic transitions in grasses. We explored whether evolution of C4 photosynthesis correlates with niche expansions, niche changes, or stasis at subfamily level and within the two tribes Paniceae and Paspaleae. We compared the climatic extremes of growing season temperatures, aridity, and mean temperatures of the coldest months. We found support for all the known biogeographic distribution patterns of C4 species, these patterns were, however, formed both by niche expansion and niche changes. The only ubiquitous response to a change in the photosynthetic pathway within Panicoideae was a niche expansion of the C4 species into regions with higher growing season temperatures, but without a withdrawal from the inherited climate niche. Other patterns varied among the tribes, as macro-climatic niche evolution in the American tribe Paspaleae differed from the pattern supported in the globally distributed tribe Paniceae and at family level.Fil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Biganzoli, Fernando. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Métodos Cuantitativos y Sistemas de Información; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Bena, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Godoy Bürki, Ana Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Reinheimer, Renata. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Zuloaga, Fernando Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Areas of vascular plants endemism in the Monte desert (Argentina)

In order to identify concordant distributions of endemic vascular plants in the Monte desert, we analyzed the distributional data of 180 species endemic to the Monte desert with the optimality criterion implemented in the program VNDM. We detected 13 partially overlapping areas of vascular plant endemism.The main areas of endemism are distributed from north to south associated with the mountainous region of the Precordillera of the Andes towards the west of the study region. These main areas correspond to environments with important variation in elevation and aridity, whereas minor areas correspond to patches of the steppe vegetation towards the east of the study region. We also obtained extensive areas covering much of the Monte desert, coincident with the two classical biogeographic units proposed. In agreement with the general arid climate of the Monte, most of the endemic flora inhabits arid and/or semiarid environments.Fil: Elías, Gabriela del Valle. Universidad Nacional de Chilecito; ArgentinaFil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentin

Sequence length variation, indel costs, and congruence in sensitivity analysis

The behavior of two topological and four character-based congruence measures was explored using different indel treatments in three empirical data sets, each with different alignment difficulties. The analyses were done using direct optimization within a sensitivity analysis framework in which the cost of indels was varied. Indels were treated either as a fifth character state, or strings of contiguous gaps were considered single events by using linear affine gap cost. Congruence consistently improved when indels were treated as single events, but no congruence measure appeared as the obviously preferable one. However, when combining enough data, all congruence measures clearly tended to select the same alignment cost set as the optimal one. Disagreement among congruence measures was mostly caused by a dominant fragment or a data partition that included all or most of the length variation in the data set. Dominance was easily detected, as the character-based congruence measures approached their optimal value when indel costs were incremented. Dominance of a fragment or data partition was overwhelmed when new sequence length-variable fragments or data partitions were added. The Willi Hennig Society 2005. Since DNA sequence analysis has become a standard technique for phylogenetic inference at all taxonomic levels, there has been a growing demand for phylo

Rehabilitation of the south american genus ochetophila poepp. ex endl. (Rhamnaceae: Colletieae)

Recent molecular and morphological analyses show that Discaria is polyphyletic and consists of two separate clades, Discaria sens. str. and a clade of two species from Chile and Argentina: D. trinervis and D. nana. The genus Ochetophila is here reinstated to accommodate these two species. A revised synonymy is presented, and a new combination is provided for O. nana.Fil: Kellermann, J.. University of Melbourne; AustraliaFil: Medan, Diego. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Recursos Naturales y Ambiente. Cátedra de Botánica Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; ArgentinaFil: Hilger, H.H.. Freie Universität Berlin; Alemani

Consensus in the search for areas of endemism

For ambiguous data sets, methods to determine areas of endemism based on an optimality criterion may result in large numbers of candidate areas, and thus some kind of consensus technique is required to summarize those results. This paper presents a formal description of two possible algorithms or rules for area consensus, which merge candidate areas if they share a user-defined percentage of the species that define each candidate area. The two consensus rules summarize ambiguity in different ways. Applying the ?tight? rule will result in consensus areas defined by species present in nearly all cells, but in cases where there is significant conflict the result may be a high number of distinct consensus areas. The ?loose? consensus rule is more agglomerative and will result in fewer consensus areas, combining areas when overlapping distribution patterns exist. Depending on the aim and scale of the analysis, the two consensus rules can be used either to delimit areas of endemism with sharp boundaries or to identify diffuse and gradually replacing biogeographical patterns. These two different approaches are discussed and demonstrated using real data.Fil: Aagesen, Lone. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion; ArgentinaFil: Szumik, Claudia Adriana. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Superior de Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; ArgentinaFil: Goloboff, Pablo Augusto. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto Superior de Entomología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tucumán; Argentin