| Titre | Introducing Pulcheripollenites sweetii in honour of the late Dr. A.R. Sweet, as part of a revised stratophenetic framework for Pulcheripollenites spp. |
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| Auteur | Bell, K M |
| Source | The 51st Annual Meeting of AASP-The Palynological Society and Annual General Meeting of the Canadian Association of Palynologists (CAP), programs and abstracts; 2018 p. 9 |
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| Année | 2018 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20180259 |
| Réunion | The 51st Annual Meeting of AASP-The Palynological Society and Annual General Meeting of the Canadian Association of Palynologists (CAP); Calgary, AB; CA; août 5-10, 2018 |
| Document | livre |
| Lang. | anglais |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Sujets | paléontologie systématique; taxonomie; évolution; fossiles; biostratigraphie; morphologie des fossiles; Crétacé supérieur; Campanien; Maestrichtien; Formation d'Horseshoe Canyon ; paléontologie;
stratigraphie; Phanérozoïque; Mésozoïque; Crétacé |
| Programme | GEM2 : La géocartographie de l'énergie et des minéraux Bouclier à Selwyn du corridor de Mackenzie |
| Diffusé | 2018 08 01 |
| Résumé | (disponible en anglais seulement)
When the genus Pulcheripollenites was first designated, three species attributed to this genus (P. inrasus, P. krempii and P. narcissus) were described from the
lower part of the Horseshoe Canyon (formerly Edmonton) Formation of central Alberta (Srivastava, 1969). This genus was not recognized as having significant biostratigraphic value as all holotypes came from a single sample now considered to be of late
Campanian age. Subsequent studies of Campanian and Maastrichtian strata from west-central Alberta, east-central Yukon Territory and west-central Northwest Territories reveals that the described species of Pulcheripollenites have distinct
biostratigraphic ranges. The re-description of three existing species (P. inrasus, P. krempii and P. narcissus), the generic reassignment of a single species (P. pseudomagnificus), and the description of a new species (P. sweetii), along with the
documentation of these five species over an extended stratigraphic interval, allows the recognition of biostratigraphic and stratophenetic trends within the Pulcheripollenites complex of species.
The upper age range of Pulcheripollenites has been
established as being late Maastrichtian, with P. sweetii and P. pseudomagnificus both associated with assemblage 9 and P. sweetii also associated with assemblage 10 of Nichols and Sweet (1993). The lower age range of Pulcheripollenites in northern
Canada is late Campanian with P. narcissus found in association with assemblage 6 taxa (Nichols and Sweet, 1993). Observed through the late Campanian and Maastrichtian are changes: 1) in the polar outline from sub-triangular, to rounded-triangular,
to sub-circular; 2) in the equatorial outline from oblate to sub-circular; 3) in the aperture style from brevicolpate, to elongate and then equidimensional pores; 4) in the compound ectexinal sculpture from dominantly striate with prominent lirae and
reduced interlirae muri to a more fine and even reticulation; 5) from a tectate margo bordering the colpi to an entirely intectate ectexine; 6) from a footlayer of approximately uniform thickness to one thickening towards and sometimes protruding at
the aperture and; 7) in pollen grain diameter, with reduction in size through time. The recognition of these trends within Pulcheripollenites enhances the biostratigraphic utility of this genus in the upper Campanian and Maastrichtian of North
America. |
| Sommaire | (Résumé en langage clair et simple, non publié)
La valeur biostratigraphique des espèces de pollen appartenant au genre Pulcheripollenites n'était pas reconnue auparavant. La redescription
d'espèces existantes et la description d'une nouvelle espèce, ainsi que l'enregistrement d'informations les concernant sur un intervalle stratigraphique prolongé au Yukon et dans la partie centrale ouest des Territoires du Nord-Ouest, révèlent des
tendances qui améliorent l'utilité de ce genre pour ce qui est d'établir la corrélation biostratigraphique relative au Crétacé tardif. |
| GEOSCAN ID | 312993 |
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