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Mendoza-Cifuentes H.,National University of Colombia | Fernandez-Alonso J.L.,Real Jardin Botanico RJB CSIC
Anales del Jardin Botanico de Madrid | Year: 2012

A historical review, the circumscription problems and nomenclatural changes based upon a phylogenetic morphological analysis of the genus Centronia are presented. In this framework, four Andean species of Centronia are transfered to thegenus Meriania (M. brachycera, M. haemantha, M. mutabilis and M. mutisii) and five new speciesrelated to this group (M. aguaditensis, M. arizae, M. silverstonei, M. sararensis and M. yalconensis) and three new subspecies of M. haemantha (subsp. chaponensis, subsp. orientalis and subsp. virolinensis) are described. The selection of lectotypes of M. haemantha and M. mutisii is made and four names Centronia eximia, C. pulchra, C. dichromantha and C. insignis, are considered synonyms. We argue that this group of nine species is a natural group witthin the genus Meriania, and present taxonomic revision. Source

Inda L.A.,University of Zaragoza | Sanmartin I.,Real Jardin Botanico RJB CSIC | Buerki S.,Jodrell Laboratory | Catalan P.,University of Zaragoza
Journal of Biogeography | Year: 2014

Aim: The biogeography of the grass genera Festuca (subgenus Schedonorus) and Lolium, which form one of the world main forage groups, is here reconstructed for the first time using nuclear and plastid DNA data. We aimed to test previous hypotheses on the origin of the group ancestor and on the Holocene versus pre-Holocene dispersals of the most recent fodder grasses. Location: The Mediterranean Basin and neighbouring regions: North Africa, Southwest Asia, East and West Africa, and Eurasia. Methods: Sampling included nearly all representatives from the native Old World distribution of this group. We used maximum parsimony, maximum likelihood and Bayesian inference methods to reconstruct phylogenetic relationships. Divergence times were estimated with a Bayesian relaxed clock and secondary calibrations derived from a fossil-dated phylogeny of grasses. Biogeographical scenarios were reconstructed with Bayesian-averaged dispersal-vicariance analysis (Bayes-DIVA) and dispersal-extinction-cladogenesis (DEC), using a stratified palaeogeographical model spanning the last 12 million years. Results: Meadow fescue (Festuca pratensis) originated in Eurosiberia, Southwest Asia, 2 million years ago (Ma), whereas ryegrasses (Lolium) first diversified in the eastern Mediterranean region around 4.1 Ma, splitting into two autogamous versus allogamous lineages, with Macaronesian Lolium embedded within the latter. An alternative scenario suggests, however, an early split of the Macaronesian ryegrasses. Our results support the hybrid origin of the tall fescue (Festuca arundinacea). Main conclusions: The ancestor of the fescues and ryegrasses originated in the western Mediterranean in the mid-Miocene. The sister relationship of the tropical African Festuca simensis to Lolium is a novel finding, suggesting a dispersal of the ancestor of the ryegrasses from Asia to East Africa in the early Pliocene. Our reconstruction rejects the hypothesis of a single Neolithic human-mediated dispersal of Lolium species from eastern to western Mediterranean areas, suggesting instead a pre-agricultural distribution of Lolium ancestors along the Mediterranean Basin since the Pliocene. © 2013 John Wiley & Sons Ltd. Source

Vitales D.,University of Barcelona | Garnatje T.,Institute Botanic Of Barcelona Ibb Csic Icub | Pellicer J.,Jodrell Laboratory | Valles J.,University of Barcelona | Sanmartin I.,Real Jardin Botanico RJB CSIC
BMC Evolutionary Biology | Year: 2014

Background: Considered a biodiversity hotspot, the Canary Islands have been the key subjects of numerous evolutionary studies concerning a large variety of organisms. The genus Cheirolophus (Asteraceae) represents one of the largest plant radiations in the Canarian archipelago. In contrast, only a few species occur in the Mediterranean region, the putative ancestral area of the genus. Here, our main aim was to reconstruct the phylogenetic and biogeographic history of Cheirolophus with special focus on explaining the origin of the large Canarian radiation. Results: We found significant incongruence in phylogenetic relationships between nuclear and plastid markers. Each dataset provided resolution at different levels in Cheirolophus: the nuclear markers resolved the backbone of the phylogeny while the plastid data provided better resolution within the Canarian clade. The origin of Cheirolophus was dated in the Mid-Late Miocene, followed by rapid diversification into the three main Mediterranean lineages and the Macaronesian clade. A decrease in diversification rates was inferred at the end of the Miocene, with a new increase in the Late Pliocene concurrent with the onset of the Mediterranean climate. Diversification within the Macaronesian clade started in the Early-Mid Pleistocene, with unusually high speciation rates giving rise to the extant insular diversity. Conclusions: Climate-driven diversification likely explains the early evolutionary history of Cheirolophus in the Mediterranean region. It appears that the exceptionally high diversification rate in the Canarian clade was mainly driven by allopatric speciation (including intra- and interisland diversification). Several intrinsic (e.g. breeding system, polyploid origin, seed dispersal syndrome) and extrinsic (e.g. fragmented landscape, isolated habitats, climatic and geological changes) factors probably contributed to the progressive differentiation of populations resulting in numerous microendemisms. Finally, hybridization events and emerging ecological adaptation may have also reinforced the diversification process. © 2014 Vitales et al.; licensee BioMed Central Ltd. Source

The role of Quaternary climatic shifts in shaping the distribution of Linaria elegans, an Iberian annual plant, was investigated using species distribution modelling and molecular phylogeographical analyses. Three hypotheses are proposed to explain the Quaternary history of its mountain ring range. The distribution of L. elegans was modelled using the maximum entropy method and projected to the last interglacial and to the last glacial maximum (LGM) using two different paleoclimatic models: the Community Climate System Model (CCSM) and the Model for Interdisciplinary Research on Climate (MIROC). Two nuclear and three plastid DNA regions were sequenced for 24 populations (119 individuals sampled). Bayesian phylogenetic, phylogeographical, dating and coalescent-based population genetic analyses were conducted. Molecular analyses indicated the existence of northern and southern glacial refugia and supported two routes of post-glacial recolonization. These results were consistent with the LGM distribution as inferred under the CCSM paleoclimatic model (but not under the MIROC model). Isolation between two major refugia was dated back to the Riss or Mindel glaciations, > 100 kyr before present (bp). The Atlantic distribution of inferred refugia suggests that the oceanic (buffered)-continental (harsh) gradient may have played a key and previously unrecognized role in determining Quaternary distribution shifts of Mediterranean plants. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust. Source

Mateo R.G.,Real Jardin Botanico RJB CSIC | de la Estrella M.,University of Cordoba, Spain | Felicisimo A.M.,University of Extremadura | Munoz J.,Real Jardin Botanico RJB CSIC | And 2 more authors.
Biological Conservation | Year: 2013

Knowledge about spatial biodiversity patterns is a basic criterion for reserve network design. Although herbarium collections hold large quantities of information, the data are often scattered and cannot supply complete spatial coverage. Alternatively, herbarium data can be used to fit species distribution models and their predictions can be used to provide complete spatial coverage and derive species richness maps. Here, we build on previous effort to propose an improved compositionalist framework for using species distribution models to better inform conservation management. We illustrate the approach with models fitted with six different methods and combined using an ensemble approach for 408 plant species in a tropical and megadiverse country (Ecuador). As a complementary view to the traditional richness hotspots methodology, consisting of a simple stacking of species distribution maps, the compositionalist modelling approach used here combines separate predictions for different pools of species to identify areas of alternative suitability for conservation. Our results show that the compositionalist approach better captures the established protected areas than the traditional richness hotspots strategies and allows the identification of areas in Ecuador that would optimally complement the current protection network. Further studies should aim at refining the approach with more groups and additional species information. © 2013 Elsevier Ltd. Source

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