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The medullosan pteridosperm ovule Stephanospermum Brongniart is a well-known component of Carboniferous aged coal-ball and siderite nodule floras from North America and Europe but also occurs in the Permian floras of Cathaysia where it is represented by the Lopingian (late Permian) aged species Stephanospermum trunctatum (Li) Wang et al. (2009) from coal-balls in the Wangjiazhai Formation in Southern...
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