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晚古生代同处于赤道或低纬度地带的中国大陆植物群与欧美地区同期植物群之间总存在一定的差异。中泥盆世—早石炭世维宪期，中国大陆以石松类的大量繁育和高度分异为显著特色，而同期的欧美地区植物群以古蕨类和前裸子植物为其主体；纳缪尔期—二叠纪，大量东亚型鳞木类植物及许多地方性植物属相继在中国大陆出现，使它和欧美植物群之间的差距进一步拉大。造成两地植物组分差异的主要原因可能与当时气候的经向变化有关（主要是两地距离古特提斯洋远近不同，从而导致湿度有别）。
In the Late Paleozoic, there were always some differences between the flora of mainland China and the flora of the same period in Europe and the United States in the equatorial or lower latitudes. In the Middle Devonian-Early Carboniferous Period, China was characterized by large numbers of sparrows and highly differentiated species, while the flora of Europe and the United States dominated ancient ferns and former gymnosperms in the same period. Permian - Permian, a large number of East Asian scales and woody plants and many endemic plants have emerged in mainland China, making it and Europe and the United States flora further widened the gap between. The main reason for the differences in plant components between the two places may be related to the meridional changes of the climate at that time (mainly because the two places are different in distance from the ancient Tethys Ocean, resulting in different degrees of humidity).