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词条 Baragwanathia
释义
Baragwanathia
fossil plant genus
genus of early lycopsid plants (plant) that had true leaves (leaf) bearing a single strand of vascular tissue (vascular system) and kidney-bean-shaped sporangia arranged in zones along the stem. These features relate it to both ancient and modern club mosses (club moss). The first confirmed occurrence of Baragwanathia is in Australian rocks that date from Late Silurian (Silurian Period) times (about 420 million years ago). This discovery suggests that the lycopsids were the first lineage of land plants to evolve tracheids (tracheid), true leaves, and a large stature. It also implies that the evolutionary split between lycopsids and all other vascular plants occurred very early in their colonization of terrestrial environments. This genus is also known from the Early Devonian (Devonian Period) Epoch (about 416 to 398 million years ago) of Australia and the Late Devonian Epoch of Canada (about 385 to 360 million years ago). Baragwanathia grew up to 28 cm (11 inches) long.
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更新时间:2025/2/21 9:29:41