Origin and differentiation of endemism in the flora of China

摘要: The present paper analyzed 239 endemic genera in 67 families the flora of seed plants China. results showed that there are five containing more than ten genera, namely, Gesneriaceae (27), which hereafter refers to number China, Composite (20), Labiatae (12), Cruciferae (11), and Umbelliferae (10), 15 with two another 30 only one genus. Four monotypic (Ginkgoaceae, Davidiaceae, Eucommiaceae Acanthochlamydaceae) most ancient, relict characteristic Based on integrative data systematics, fossil history, morphological molecular evidence these their origin, evolution relationships were discussed. In gymnosperms, all relicts Arctic-Tertiary flora, having earlier evolutionary can be traced back Cretaceous or Jurassic even earlier. angiosperms, mostly relicts, represented lineages “Eight-Class System Classification Angiosperms”, endemism found almost every stage extant angiosperms. once occupied huge areas northern hemisphere Tertiary late Cretaceous, while neo-endemism originated Tertiary. They came from Arctic-Tertiary, Paleo-tropical-Tertiary Tethys-Tertiary florisitic elements, blend three elements many autochthonous origin. was formed when some dispersal routes such as North Atlantic Land Bridge, Bering Bridge became discontinuous during Tertiary, well climate change glaciations Quaternary. Therefore, is starting point