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Hanskerpia gen. nov. and phylogenetic relationships among the most ancient conifers (Voltziales)
A new fossilized walchian (Voltziales) conifer plant from the Late Pennsylvanian Hamilton Quarry of Kansas, U.S.A. combines morphological characters of the morphogenus Walchia and the fossil plantExpand
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Characterizing the Most Primitive Seed Ferns. I. A Reconstruction of Elkinsia polymorpha
Abundant gymnospermous remains occur in association with Elkinsia polymorpha in Upper Devonian deposits near Elkins, West Virginia, and these provide an opportunity to characterize and further refineExpand
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Elkinsia gen. nov., a Late Devonian Gymnosperm with Cupulate Ovules
An extensive collection of fossilized ovules, ovulate cupules, and cupuliferous branching systems from late Devonian deposits of eastern West Virginia is described and named Elkinsia polymorpha gen.Expand
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The fossil monocot Limnobiophyllum scutatum: resolving the phylogeny of Lemnaceae.
More than 200 specimens of Limnobiophyllum scutatum (Dawson) Krassilov have been recovered from lacustrine claystones in the Paleocene Paskapoo Formation near Red Deer, Alberta. The plant was aExpand
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Todea from the Lower Cretaceous of western North America: implications for the phylogeny, systematics, and evolution of modern Osmundaceae.
The first fossil evidence for the fern genus Todea has been recovered from the Lower Cretaceous of British Columbia, Canada, providing paleontological data to strengthen hypotheses regarding patternsExpand
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The callistophytales (Pteridospermopsida): Reproductively sophisticated paleozoic gymnosperms
Abstract The Callistophytales nov. order is proposed for a small family of Pennsylvanian and possibly Permian pteridosperms. Plants conform to two species of Callistophyton and their reproductiveExpand
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An herbaceous fossil conifer: Gymnospermous ruderals in the evolution of Mesozoic vegetation
Abstract Fast growing conifers have been recognized in disturbed habitats of the transitional Lower Middle Triassic Gres a Voltzia delta from the Buntsandstein in eastern France. These herbaceousExpand
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Is the anthophyte hypothesis alive and well? New evidence from the reproductive structures of Bennettitales.
Bennettitales is an extinct group of seed plants with reproductive structures that are similar in some respects to both Gnetales and angiosperms, but systematic relationships among the three cladesExpand
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