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1.
Mol Phylogenet Evol ; 159: 107105, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33601026

RESUMEN

Angraecoid orchids present a remarkable diversity of chromosome numbers, which makes them a highly suitable system for exploring the impact of karyotypic changes on cladogenesis, diversification and morphological differentiation. We compiled an annotated cytotaxonomic checklist for 126 species of Angraecinae, which was utilised to reconstruct chromosomal evolution using a newly-produced, near-comprehensive phylogenetic tree that includes 245 angraecoid taxa. In tandem with this improved phylogenetic framework, using combined Bayesian, maximum likelihood and parsimony approaches on ITS-1 and five plastid markers, we propose a new cladistic nomenclature for the angraecoids, and we estimate a new timeframe for angraecoid radiation based on a secondary calibration, and calculate diversification rates using a Bayesian approach. Coincident divergence dates between clades with identical geographical distributions in the angraecoids and the pantropical orchid genus Bulbophyllum suggest that the same events may have intervened in the dispersal of these two epiphytic groups between Asia, continental Africa, Madagascar and the Neotropics. The major angraecoid lineages probably began to differentiate in the Middle Miocene, and most genera and species emerged respectively around the Late Miocene-Pliocene boundary and the Pleistocene. Ancestral state reconstruction using maximum likelihood estimation revealed an eventful karyotypic history dominated by descending dysploidy. Karyotypic shifts seem to have paralleled cladogenesis in continental tropical Africa, where approximately 90% of the species have descended from at least one inferred transition from n = 17-18 to n = 25 during the Middle Miocene Climatic Transition, followed by some clade-specific descending and ascending dysploidy from the Late Miocene to the Pleistocene. Conversely, detected polyploidy is restricted to a few species lineages mostly originating during the Pleistocene. No increases in net diversification could be related to chromosome number changes, and the apparent net diversification was found to be highest in Madagascar, where karyotypic stasis predominates. Finally, shifts in chromosome number appear to have paralleled the evolution of rostellum structure, leaflessness, and conspicuous changes in floral colour.


Asunto(s)
Evolución Biológica , Especiación Genética , Cariotipo , Orchidaceae/clasificación , Filogenia , África , Asia , Teorema de Bayes , Funciones de Verosimilitud , Madagascar , Orchidaceae/genética , Filogeografía , Plastidios/genética
2.
Mol Phylogenet Evol ; 126: 241-249, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29673694

RESUMEN

Despite significant progress made in recent years toward developing an infrafamilial classification of Orchidaceae, our understanding of relationships among and within tribal and subtribal groups of epidendroid orchids remains incomplete. To reassess generic delimitation among one group of these epidendroids, the African angraecoids, phylogenetic relationships were inferred from DNA sequence data from three regions, ITS, matK, and the trnL-trnF intergenic spacer, obtained from a broadly representative sample of taxa. Parsimony and Bayesian analyses yielded highly resolved trees that are in clear agreement and show significant support for many key clades within subtribe Angraecinae s.l. Angraecoid orchids comprise two well-supported clades: an African/American group and an Indian Ocean group. Molecular results also support many previously proposed relationships among genera, but also reveal some unexpected relationships. The genera Aerangis, Ancistrorhynchus, Bolusiella, Campylocentrum, Cyrtorchis, Dendrophylax, Eurychone, Microcoelia, Nephrangis, Podangis and Solenangis are all shown to be monophyletic, but Angraecopsis, Diaphananthe and Margelliantha are polyphyletic. Diaphananthe forms three well-supported clades, one of which might represent a new genus, and Rhipidoglossum is paraphyletic with respect to Cribbia and Rhaesteria, and also includes taxa currently assigned to Margelliantha. Tridactyle too is paraphyletic as Eggelingia is embedded within it. The large genus Angraecum is confirmed to be polyphyletic and several groups will have to be recognized as separate genera, including sections Dolabrifolia and Hadrangis. The recently segregated genus Pectinariella (previously recognized as A. sect. Pectinaria) is polyphyletic and its Continental African species will have to be removed. Similarly, some of the species recently transferred to Angraecoides that were previously placed in Angraecum sects. Afrangraecum and Conchoglossum will have to be moved and described as a new genus.


Asunto(s)
Orchidaceae/clasificación , Filogenia , Teorema de Bayes , ADN de Plantas/genética , Océano Índico , Orchidaceae/genética , Análisis de Secuencia de ADN
3.
PhytoKeys ; 243: 31-45, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38938541

RESUMEN

Linariabimaculata comb. et stat. nov., from the overlooked Central Algarve plant endemism centre, is here lectotypified and redescribed as a full species based on Linariaviscosavar.bimaculata, which was historically misidentified under allopatric L.spartea and L.viscosa. Traditional herbarium taxonomy and citizen science observations were combined to document the geographical range of the four species of Linariasubsect.Versicolores in the Algarve and amend an identification key for the Iberian clade of this subsection. Geographical patterns and morphological similarity suggest a sister relationship between L.bimaculata and L.algarviana, unveiling a new possible example of parallel speciation linked to a purple to yellow shift in corolla colour. Besides the yellow flowers, L.bimaculata differs from L.algarviana in the more elongate fertile stems and the invariably erect-patent corolla tube. It is assessed as Vulnerable (VU) according to the IUCN Categories and Criteria.

4.
Curr Biol ; 34(5): R189-R190, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38471443

RESUMEN

The world-renowned pollination system of the long-spurred orchid Angraecum sesquipedale Thouars and the long-tongued hawkmoth Xanthopan praedicta (Rothschild & Jordan, 1903), from Madagascar, is the best-known example of the predictive power of evolutionary ecology1,2, yet its actual degree of specialisation remains poorly described due to the incompleteness of the pollination record of X. praedicta. Here, we describe another species from Madagascar, an angraecoid orchid distantly related to the genus Angraecum Bory, that has evolved these extreme adaptations to a single pollinator after a pollinator shift. It bears the longest spur of any flowering plant, relative to flower diameter, reaching 33 cm. The discovery of a species with such an exceptionally long spur is a rare event, the most recent dating to 19653. This novelty is described here as Solenangis impraedicta (Figure 1A-F) and discussed in a phylogenetic framework. Its conservation status is assessed as Endangered.


Asunto(s)
Lepidópteros , Orchidaceae , Animales , Polinización , Filogenia , Madagascar , Evolución Biológica , Flores
5.
Sci Data ; 11(1): 669, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38909064

RESUMEN

Species phenology - the timing of key life events - is being altered by ongoing climate changes with yet underappreciated consequences for ecosystem stability. While flowering is generally occurring earlier, we know much less about other key processes such as the time of fruit ripening, largely due to the lack of comprehensive long-term datasets. Here we provide information on the exact date and site where seeds of 4,462 taxa were collected for the Index Seminum (seed exchange catalogue) of the Botanic Garden of the University of Coimbra, between 1926 and 2013. Seeds were collected from spontaneous and cultivated individuals across Portugal, including both native and introduced taxa. The database consists of 127,747 curated records with information on the species, or infraspecific taxa (including authority), and the day and site where seeds were collected. All records are georeferenced and provided with a confidence interval for the collection site. Taxonomy was first curated manually by in-house botanists and then harmonized according to the GBIF backbone taxonomy.


Asunto(s)
Frutas , Plantas , Cambio Climático , Ecosistema , Plantas/clasificación , Portugal , Semillas
6.
Sci Rep ; 9(1): 15792, 2019 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-31690834

RESUMEN

The Azores, Madeira, Selvagens, Canary Islands and Cabo Verde are commonly united under the term "Macaronesia". This study investigates the coherency and validity of Macaronesia as a biogeographic unit using six marine groups with very different dispersal abilities: coastal fishes, echinoderms, gastropod molluscs, brachyuran decapod crustaceans, polychaete annelids, and macroalgae. We found no support for the current concept of Macaronesia as a coherent marine biogeographic unit. All marine groups studied suggest the exclusion of Cabo Verde from the remaining Macaronesian archipelagos and thus, Cabo Verde should be given the status of a biogeographic subprovince within the West African Transition province. We propose to redefine the Lusitanian biogeographical province, in which we include four ecoregions: the South European Atlantic Shelf, the Saharan Upwelling, the Azores, and a new ecoregion herein named Webbnesia, which comprises the archipelagos of Madeira, Selvagens and the Canary Islands.

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