Cycads: Fossil evidence of late Paleozoic origin

S.H. Mamay

doi:10.1126/science.164.3877.295

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Cycads: Fossil evidence of late Paleozoic origin

S.H. Mamay

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Abstract

Plant fossils from Lower Permian strata of the southwestern United States have been interpreted as cycadalean megasporophylls. They are evidently descended from spermopterid elements of the Pennsylvanian Taeniopteris complex; thus the known fossil history of the cycads is extended from the Late Triassic into the late Paleozoic. Possible implications of the Permian fossils toward evolution of the angiosperm carpel are considered.

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Source-reported bounding extent: 31.51165355321558° to 42.80355799625093° latitude; -123.44473262679031° to -101.80612866259875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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S.H. Mamay. 1969. Cycads: Fossil evidence of late Paleozoic origin. https://doi.org/10.1126/science.164.3877.295

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