Abstract:The Annonaccae,a pantropic family, is well developed in tropical regions of both Old and New Worlds, mainly at low elevations in moist forests.In warm temperate E.North America, subtropical South America,S. Africa and N. Australia there are only a few species and comparatively rare in Madagascar and in the islands of the Pacific.According to the J.Hutchinson's system, the family comprises 2 subfamilies,3 tribes,2 subtribes,129 genera and about 2287 species. The subfamily Annonoideae has 127 genera, about 2247 species.The subfamily Monodoroideae with 2 genera, about 40 species. confined to Africa including Madagasscar. The Annonaceae is by far the largest family of Annonales. About a third of the species belong to only 5 genera,viz. Guatteria (255),Uvaria (177),Polyalthia (171), Xylopia (159) and Annona (126). The greatest concentration of genera and species is in Indo-Malaysian area of Asia. According to the continental drift and the plate tectonic theories, the origin and the formation of recent distributional patterns of this family were discussed. It is suggested that the early diversity centre of Annonaceae is in the north part of West Gondwanaland. Thus,the family Annonaceae has come into existence since late Cretaceous.In China, the Annonaceae comprises 23 genera (except Annona and Cananga), 103 species and 2varieties. Among them, 45 species and 1 variety are endemic to China. Yunnan is the richest province in species of the family in the country. There is no endemic genus of Annonaceae in China.In this paper the genera in China are classified into 6 distribution patterns, namely: 1.Pantropic (1 genus); 2. Trop. Asia & Trop. Amer .disjunct (1 genus); 3. Old World Tropics (3 genera);4. Trop. Asia & Trop. Australasia (6 genera); 5. Trop. Asia to Trop. Africa (2 genera); 6. Trop.Asia (Indo-Malesia) (10 genera).Some distribution maps of genera in China and statistics of genera in the floristic regions of the world and China are presented .
