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1.
PhytoKeys ; 241: 65-79, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38638578

RESUMEN

The new species, Thliphthisasapphussp. nov. (Rubiaceae, Rubieae), a narrow endemic of the white cliffs of Lefkátas on the southwest coast of Lefkada (Greece) is described and illustrated and an IUCN assessment is presented. Vegetation relevés were performed at the single known locality, limestone cliffs facing the sea and revealed a new association, the Thliphthisasapphus-Lomelosietumdallaportae. The chromosome number of Thliphthisasapphus was determined as 2n = 4x = 44, being the single tetraploid species in the genus to date. The species also differs markedly morphologically from its morphologically closest relatives, two Greek steno-endemic oreophytes, Th.baenitzii and Th.muscosa by the following characters: densely setose mericarps and corolla, tetraploidy and by its distribution. An identification key for the Greek species of Thliphthisa is provided. Th.sapphus constitutes the westernmost outpost of a group of Greek steno-endemics, highlighting the importance of coastal habitats and their protection as refugia for poorly competitive chamaephytes.

2.
Ecol Lett ; 15(12): 1439-48, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23006492

RESUMEN

The Convention on Biological Diversity (CBD) aims at the conservation of all three levels of biodiversity, that is, ecosystems, species and genes. Genetic diversity represents evolutionary potential and is important for ecosystem functioning. Unfortunately, genetic diversity in natural populations is hardly considered in conservation strategies because it is difficult to measure and has been hypothesised to co-vary with species richness. This means that species richness is taken as a surrogate of genetic diversity in conservation planning, though their relationship has not been properly evaluated. We tested whether the genetic and species levels of biodiversity co-vary, using a large-scale and multi-species approach. We chose the high-mountain flora of the Alps and the Carpathians as study systems and demonstrate that species richness and genetic diversity are not correlated. Species richness thus cannot act as a surrogate for genetic diversity. Our results have important consequences for implementing the CBD when designing conservation strategies.


Asunto(s)
Biodiversidad , Variación Genética , Plantas/genética , Ecosistema , Geografía
3.
PhytoKeys ; (75): 93-106, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28127247

RESUMEN

Androsace vitaliana (syn. Vitaliana primuliflora; Primulaceae) has been subject to several taxonomic treatments, whose conclusions ranged from a single species with numerous infraspecific taxa to several species usually without infraspecific taxa. Here, following molecular investigation, several taxonomic changes are made. A single species with the following infraspecific taxa is recognized: subsp. vitaliana (Pyrenees), subsp. cinerea (south-western Alps), subsp. lepontina (Pennine Alps), subsp. sesleri (south-eastern Alps), subsp. praetutiana (Apennines) and subsp. assoana (Iberian Peninsula excluding the Pyrenees), the last of which is divided into the four allopatrically distributed varieties assoana, centriberica, flosjugorum and nevadensis. Contrary to some previous assertions, all taxa are allopatric and, especially for subspp. vitaliana, cinerea and lepontina, where clear diagnostic characters are lacking, they can best be determined by their geographic origin.

4.
Am J Bot ; 93(8): 1193-205, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21642184

RESUMEN

The plastid matK gene, trnL/F spacer, and nuclear rDNA ITS were sequenced for 36 species of Leontodon and 29 taxa of related genera of tribe Lactuceae. Phylogenetic relationships inferred from the independent and combined data are largely congruent and reveal that Leontodon sensu lato (s.l.) as presently defined is diphyletic: L. subgenus Leontodon forms a clade with Helminthotheca, Picris and Hypochaeris as sister genera, whereas L. subgenus Oporinia appears as a separate clade with strong bootstrap support and is thus better treated as a separate genus. Previous sectional classifications of Leontodon s.l. are considered in the light of DNA and additional morphological and karyological data. Support is presented for a core group of Hypochaeridinae sensu stricto (s.s.) with the two clades of Leontodon s.l., Helminthotheca, Picris, and Hypochaeris, whereas Urospermum, Hyoseris, Aposeris, and Rhagadiolus appear to be positioned more distantly.

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