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A new plant concept for the extinct conifer species Emporia lockardii (Mapes & Rothwell) Mapes & Rothwell (Emporiaceae) is developed from fossils collected at the Late Pennsylvanian Hamilton Quarry, Kansas. Emporia lockardii has lateral plagiotropic branches with simple and forked leaves, simple pollen cones, and compound ovulate cones. Stems have an endarch eustele with dense wood surrounding a septate pith. Leaves display position-dependent heterophylly with forked leaves on penultimate shoots and simple leaves on ultimate shoots. All leaves are amphistomatic with two stomatal bands and papillate epidermal cells on the adaxial surface and two basal stomatal bands and numerous trichome bases on the abaxial surface. Pollen cones are simple and have helically arranged microsporophylls and adaxial pollen sacs. Prepollen is monolete and monosaccate, and it conforms to the sporae dispersae genus Potonieisporites Bharadwaj. Ovulate cones are compound with helically arranged, forked bracts that subtend bilaterally symmetrical, axillary dwarf shoots with one to three narrow megasporophylls interspersed among numerous sterile scales. Ovules are terminal, inverted, and bilaterally symmetrical. This new reconstruction together with additional conifer reconstructions from the Hamilton Quarry locality indicate that the genus Emporia has a particularly high species diversity for walchian conifers. These findings support previous hypotheses that propose drier habitats as sites for the first appearances of plants that become dominant during the late Permian and Mesozoic. [ABSTRACT FROM AUTHOR]

A new fossilized walchian (Voltziales) conifer plant from the Late Pennsylvanian Hamilton Quarry of Kansas, U.S.A. combines morphological characters of the morphogenus Waichia and the fossil plant genus Otovicia, with cuticular characters like those of the fossil plant genus Ernestiodendron, and seed cone morphology like that of the fossil plant genus Emporia. Internal anatomical characters are basically similar to the other walchian genera for which such features are known, but some are taxonomically informative. Numerical cladistic analysis reveals that this novel combination of characters defines a new fossil plant genus and species of walchian conifers Hanskerpia hamiltonensis. This analysis provides a test of hypotheses for relationships among walchian and other ancient conifers. Results of this analysis support some previously proposed relationships among the most primitive conifers and other Paleozoic coniferophytes. However, the analysis also calls to question the validity of all previously proposed familial circumscriptions for walchian conifers, and highlights the perplexing systematic challenges posed by the most ancient fossil conifers. The unexpected species richness of voltzialean conifers is interpreted as having resulted from the evolutionary ecology of unstable environments. [ABSTRACT FROM AUTHOR]

Reconstructs Botryopteris tridentata, a Middle Pennsylvanian age filicalean fern in Baxter Springs, Kansas. Evidence of a complete vegetative frond architecture; Description of B. tridentata rhizomes, fronds, fertile pinnae, fertile pinnule lobes and sporangia; Function of fronds as foliar equivalent of stolons.