Résumés
Abstract
The only known lyginopterid cupulate seed collected from the Middle Pennsylvanian Sydney Coalfield in Nova Scotia, Canada, comprises a coalified cupule surrounding an ovate structure 3×2 mm in size that is interpreted as an ovule. The ovule is white, reflecting its calcitic mode of preservation, and lacks cellular remains. As the specimen is incomplete, a detailed taxonomic determination is not possible, but its affinities lie within the lyginopterid (or hydrasperman) pteridosperms. This significant discovery of a lyginopterid pteridosperm aug-ments previous accounts of medullosalean pteridosperms from the flora of Sydney Coalfield.
Résumé
La seule graine cupuliforme de lyginopteridée connue recueillie du terrain houiller du Pennsylvanien moyen de Sydney, en Nouvelle-Écosse, au Canada, est constituée d’une cupule carbonifiée entourant une structure ovée d’une taille de 3 mm sur 2 qui est interprétée comme un ovule. L’ovule est blanc, couleur témoignant de son mode de conservation calcitique, et il est dépourvu de fragments cellulaires. Comme le spécimen est incomplet, une détermination taxonomique détaillée n’est pas possible, mais ses affinités se manifestent dans les ptéridospermes des lyginopteridées (ou hydraspermans). Cette découverte importante d’un ptéridosperme de lyginopteridée enrichit les signalements antérieurs de ptéridospermes médullosés de la flore du terrain houiller de Sydney.
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