Kingdom Plantae Class Isoetopsida Family Isoetaceae | Division Lycopodiophyta Order Isoetales Genus Isoetes | |
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Isoetes beestonii is the oldest known species of the living quillwort genus from the latest Permian of New South Wales and Queensland. Originally considered earliest Triassic, it is now known to be latest Permian in age, immediately after the Permian Triassic mass extinction.
Description
Isoetes beestonii is preserved as whole plants in life position within bedding planes, and presumably lived as an early successional weed in lake and pond sedimentary environments, like living Isoetes. Its leaves were wider and more succulent than modern spacies of Isoetes. Like modern Isoetes, fertile plants were little different from sterile plants, unlike Early Triassic Tomiostrobus which formed woody conelike fertile plants.
References
Isoetes beestonii Wikipedia(Text) CC BY-SA