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''Araucaria mirabilis'' is an extinct species of coniferous tree from Patagonia, Argentina. It belongs to the section ''Bunya'' (the only living species of which is ''Araucaria bidwillii'' from Australia) of the genus ''Araucaria''. ''A. mirabilis'' are known from large amounts of very well preserved silicified wood and cones from the Cerro Cuadrado Petrified Forest, including tree trunks that reached in height in life. The site was buried by a volcanic eruption during the Middle Jurassic, approximately 160 million years ago. ==Discovery== Fossils of ''Araucaria mirabilis'' are found in great abundance in the Cerro Cuadrado Petrified Forest of Patagonia, Argentina. They were the dominant species of a forest buried by a volcanic eruption about 160 million years ago.〔 The petrified forests of ''A. mirabilis'' were first discovered in 1919 by the German-Argentinean botanist Anselmo Windhausen. Noting that petrified cones were being kept as souvenirs by local farmers in the area, he explored the region and discovered the site of the petrified forests in 1923. He sent the specimens he collected to the German botanist Walther Gothan in Berlin in 1924. Gothan named them ''Araucaria windhauseni'' in honor of Windhausen in 1925. However, the Italian-Argentinean botanist Carlos Luigi Spegazzini had also acquired specimens from the petrified forest from various sources. He tentatively identified the specimens as ''Araucarites mirabilis'' in 1924.〔 An American paleontological expedition led by Elmer S. Riggs (1923–1924) of the Field Museum of Natural History also discovered the petrified forests. The numerous specimens Riggs collected (who identified them as ''Araucaria'') were later described by the American paleontologist and paleobotanist George Reber Wieland as ''Proaraucaria elongata'' (1929), ''Proaraucaria mirabilis'' (1935), and ''Proaraucaria patagonica'' (1935). Wieland and Gothan interpreted the absence of separate petrified seeds as evidence that the cones did not shed their scales at the final growth year. This was originally stated by Wieland as a justification for its classification under a new genus ''Proaraucaria''.〔 An emended description was published by the Scottish paleobotanist Mary Gordon Calder in 1953. Calder questioned the conclusions of Wieland and Gothan. She also discarded the earlier classification of Spegazzini of ''Araucarites''. The latter is a form genus, usually used for incomplete plant fossil specimens that resemble ''Araucaria'' but lack enough preserved details for more accurate classifications. Citing striking similarities with the extant ''Araucaria bidwillii'', Calder reclassified the specimens as ''Araucaria mirabilis''.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Araucaria mirabilis」の詳細全文を読む スポンサード リンク
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