trié(s) par (Pertinence décroissant(e), Titre croissant(e)) 

Himantoglossum hircinum (Lizard Orchid) reviewed in the light of new morphological and molecular observations / Richard M. Bateman in New Journal of botany, vol. 3, n°2 (Année 2013)

Public [article]  inNew Journal of botany > vol. 3, n°2 (Année 2013) . - pp. 122-140 Titre : Himantoglossum hircinum (Lizard Orchid) reviewed in the light of new morphological and molecular observations Type de document : texte imprimé Auteurs : Richard M. Bateman, Auteur ; Paula J. Rudall, Auteur ; Julie A. Hawkins, Auteur ; Gábor Sramkó, Auteur Année de publication : 2013 Article en page(s) : pp. 122-140 Langues : Anglais (eng) Catégories : [ZG] Royaume-Uni [Espèces (in biblio)] Himantoglossum hircinum (L.) Spreng. Mots-clés : ontogenèse florale  répartition géographique  espaceur interne transcrit  LEAFY  morphométrique  changement climatique Résumé : "Himantoglossum hircinum is one of the rarer and more charismatic orchids in the British flora. Morphometric comparison of the two largest and best-known populations in southern England – the coastal dune population at Sandwich and the chalk grassland population at Newmarket – using 46 characters showed that they differ only subtly, the Sandwich plants being on average more vegetatively robust and slightly more darkly pigmented, but possessing less extensive lip-spots and substantially longer ‘arms’. A comparatively morphologically divergent semi-desert population from Ifrane, Morocco differs from the English populations in having broader stems, less recurved ‘arms’, a more strongly down-curved spur and in lacking near-circular spots within the sepals. Molecular comparison of 46 plants, representing 13 English populations and 18 populations from Continental Europe and Morocco, revealed only subtle distinctions in the high-copy nuclear region ITS, and smaller-scale comparisons of the low-copy nuclear (LEAFY) and plastid (four intron) regions proved to be even less discriminatory. These results reinforce prior morphological inferences that H. hircinum is a cohesive species. Scanning electron microscopy elucidated the ontogeny of these remarkable flowers, suggesting that the exceptionally elongate central labellar lobe originated by accelerated heterochronic growth and showing that the characteristic spiral torsion always runs counter-clockwise. Lateral fusion of the paired viscidia is convergent with several other lineages of subtribe Orchidinae. Review of pollination and life-history features of H. hircinum suggest that they are typical of food-deceptive species within Orchidinae. The Lizard Orchid is infamous for geographic mobility; its cycles of expansion and contraction through the last century have been interpreted as reflecting a net northward migration in response to recent climate change. Our data tentatively suggest relatively recent colonisation of Morocco at high altitudes and an overall northwestward direction of migration into the UK. ITS ribotypes indicate multiple immigration events leading to levels of genetic diversity in England comparable with those on the Continent. A non-recent origin is inferred for H. hircinum which, despite recent systematic revisions, may harbour further cryptic species; the taxonomic status of supposed outlying populations in southern Italy in particular is questioned by the present genetic data." (source : auteurs) Type de publication : périodique Référence biblio : Bateman R., Rudall P., Hawkins J., Sramkó G., 2013 - Himantoglossum hircinum (Lizard Orchid) reviewed in the light of new morphological and molecular observations. New Journal of botany, 3 (2) : 122-140. ID PMB : 57097 DOI : 10.1179/2042349713Y.0000000025 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=57097 [article]

Exemplaires(1)

Cote	Localisation	Disponibilité
P0130-5	Brest	Exclu du prêt

Morphometric comparison of British Pseudorchis albida with Icelandic P. straminea (Orchidaceae: Orchidinae) / Richard M. Bateman in New Journal of botany, vol. 7, n°2-3 (Année 2017)

Public [article]  inNew Journal of botany > vol. 7, n°2-3 (Année 2017) . - pp. 78-93 Titre : Morphometric comparison of British Pseudorchis albida with Icelandic P. straminea (Orchidaceae: Orchidinae) Type de document : texte imprimé Auteurs : Richard M. Bateman, Auteur ; Paula J. Rudall, Auteur ; I. Denholm, Auteur Année de publication : 2018 Article en page(s) : pp. 78-93 Langues : Anglais (eng) Catégories : [Espèces (in biblio)] Pseudorchis [Espèces (in biblio)] Pseudorchis albida [ZG] Royaume-Uni et Irlande [Thèmes] Taxonomie Mots-clés : conservation  morphométrie  spéciation  aire de répartition Résumé : "Although the majority of taxonomic studies of European orchids treat Pseudorchis as a monotypic genus, some observers have argued that the apparently circumboreal segregate P. straminea should also be treated as a full species. Here, we compare detailed in vivo measurements of 55 plants from nine populations of P. albida in Britain with ten plants from three populations of P. straminea in Iceland, We apply morphometric statistics to data for 31 morphometric characters, culled from an original set of 36. We also review current (limited) DNA-based evidence of their evolutionary divergence. Of the 31 variable morphometric characters, 14 help to distinguish the two species, including labellum dimensions, spur length, flower colour, bract and leaf lengths, leaf colour and apical hooding. Molecular divergence (notably in ITS) approximates the lowest level needed for acceptance of species-level distinction, but thus far, the molecular information is typological and does not encompass seemingly intermediate populations of ‘P. tricuspis’ occurring in the mountains of central Europe. Pseudorchis has the potential to become a valuable model system for the study of speciation and subsequent inter-/post-glacial migration. Despite persistent rumours, we found no evidence that P. straminea (or ‘P. tricuspis’) occurs in the British Isles; nonetheless, this species should continue to be sought in suitable habitats in northern Scotland. Morphological variation within P. albida is comparatively low, though the most exposed of our study populations exhibits (presumably ecophenotypic) dwarfing." (source : auteurs) Type de publication : périodique Référence biblio : Bateman R., Rudall P., Denholm I., 2018 - Morphometric comparison of British Pseudorchis albida with Icelandic P. straminea (Orchidaceae: Orchidinae). New Journal of botany, 7 : 78-93. ID PMB : 66863 Permalink : http://www.cbnbrest.fr/catalogue_en_ligne/index.php?lvl=notice_display&id=66863 [article]

Exemplaires(1)

Cote	Localisation	Disponibilité
P0130-5	Brest	Exclu du prêt

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