Confirmation of Sigillaria Brongniart as a coal-forming plant in Cathaysia: occurrence from an Early Permian autochthonous peat-forming flora in Inner Mongolia

摘要

A common lycopsid genus, Sigillaria Brongniart, has been recorded most frequently in peat-forming forests in Europe and North America, but rarely in China. Although Sigillaria, in China, has been found in coal balls and used as evidence that it was a coal-forming element, it has never been recorded as compression/impressions in peat-forming settings. Recent investigation of an Early Permian autochthonous peat-forming flora of the Taiyuan Formation near Wuda, Inner Mongolia, has provided evidence that Sigillaria Could be a major element of peat-forming vegetation in China. Sigillaria is the only arborescent lycopsid acting as a major contributor to peat/coal formation. The genus Sigillaria is another element that China has in common with the Palaeozoic low-land floras of Europe and North America, enhancing the common floral aspects between the tropical swamp vegetations of the east and west regions of the Palaeotethys Ocean.