| Titre : | How many orchid species are currently native to the British Isles ? | | Type de document : | Livre | | Auteurs : | Richard M. Bateman, Auteur | | Importance : | pp. 89-110 | | Langues : | Anglais | | Catégories : | [Espèces (in biblio)] Orchidaceae
[ZG] Europe
[Thèmes] Génétique
| | Mots-clés : | classification DNA phylogénétique population génétique | | Résumé : | "The British Isles probably host the most intensively studied flora in the world, and within that flora the Orchidaceae has long been the most intensively studied family. Nonetheless, molecular phylogenetic studies performed only during the last decade have revolutionised our understanding of species relationships among European orchids, eliminating former monotypic genera such as Aceras, Coe/oglossum and Hammarbya, apportioning many former Orchis species to expanded concepts of Anacamptis and Neotinea, and combining 'Listera' into Neottia. Emphasis has now switched from species comparison to species delimitation, integrating morphometric approaches with population genetic techniques via simultaneous ordinations. Early results suggest that several distinct speciation mechanisms operate within the British and Irish orchid flora, and challenge the validity of several 'Schedule 8' species. No meaningful differences exist between British Dactylorhiza 'lapponica' and D. 'traunsteineri' , and neither represents the same allopolyploid speciation event as D. traunsteineri from the type locality in Austria. AIso, contrary to the recent Atlas of the British & Irish flora, D. majalis s.s. does not occur in the British Isles. By contrast, three habitat 'races' within Gymnadenia merit species status. Epipactis 'youngiana' is not reliably distinct from E. helleborine, whereas the autogamous E. leptochila and E. dunensis both warrant species status, alongside E. sancta recently described from Lindisfame. Controversial taxa are either widely recognised but lack biological cohesion (Emperor's New Clothes species), rarely if ever recognised but possess biological cohesion (Cinderella species, including Robinson Crusoe species recently diverged on islands such as Dactylorhiza ebudensis), or are migrating northward, presumably in response to climate change (Bleriot species, such as Serapias parviflora). Recent arrivaIs by origination or migration are partly negated by extirpation of longer established species, notably Spiranthes aestivalis and arguably Epipogium aphyllum. Present evidence suggests that the orchid flora of the British Isles (excluding the iogeographically French Channel Islands) currently consists of52 species in 20 genera; these taxa are herein reclassified in anticipation of the third edition of Stace's Flora." (source : auteur) | | Type de publication : | article de livre | | Référence biblio : | Bateman R., 2006 - How many orchid species are currently native to the British Isles ? In : Bailey J., Ellis G., Eds, 2006 - Current taxonomic research on the British & European Flora (Leicester, 13-14 September 2003). London : Botanical Society of the British Isles, 89-110. | | ID PMB : | 6456 | | Permalink : | http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=6456 |
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Affiner la rechercheDes clés pour la gestion des ressources génétiques. Quelques acquis du 3e colloque national (Toulouse, 9-11 octobre 2000) (2000)
Les gènes de la floraison in Dossier pour la science, n°HS (Année 2000)
