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A taxodiaceous seed cone from the Triassic of Antarctica
Authors:Yao X  Taylor T  Taylor E
Affiliation:1. Department of Biology, University of San Francisco, San Francisco, California 94117;2. Department of Botany and Museum of Natural History, University of Kansas, Lawrence, Kansas 66045
Abstract:A silicified seed cone is described from the lower Middle Triassic of A silicified seed cone is described from the lower Middle Triassic of Antarctica. The cone measures up to 3.4 cm long and 1.4 cm wide, and consists of helically arranged cone scales attached to a eustelic axis. Bract and ovuliferous scale are approximately of equal length and fused at the base. The bract is entire and vascularized by a single trace. The ovuliferous scale contains five distal lobes, each vascularized by a terete strand that divides to form a smaller trace to each of the five inverted ovules. Ovules are small and flattened with the three-parted integument attenuated into oppositely positioned lateral wings. The Triassic specimens are compared with both extant and fossil conifer seed cones and believed to have their closest affinities within the Taxodiaceae.
Keywords:bract  ovule  ovuliferous scale  Parasciadopitys  seed cone  Taxodiaceae  Triassic  vasculature
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