Abstract: In order to understand the distribution pattern of the extrafloral nectaried plants in the tropical rainforest in Xishuangbanna, Yunnan , China, we investigated seven forest communities ( three primary forests and four secondary forests at different ages) in Xishuangbanna Nature Reserve . Fifty-two species belonging to 36 genera and 23 families accounting for 12.3% of 424 angiosperm species in the seven communities were found to bear extrafloral nectaries ( EFNs ). Among which, eight genera and 37 species were the first time to be recorded as plants to bear EFNs. The study indicated, (1)The EFN species mainly occurred in subclasses Dilleniidae, Rosidae and Asteridae of the Magnoliopsida , and the most common EFNs were flattened glands situated on leaf blades ; (2) The proportions of EFN species within the seven communities ranged from 9.5% ( Vatica guangxiensis forest ) to 18 .5% ( Macaranga denticulata forest ), and the EFN species appeared to be more abundant in the secondary forests than those in the primary forests; (3) EFN species were disproportionally distributed among different growth forms, with the abundance being: tree > shrub > liana > herb , and no epiphytic and parasitic plants were found to bear EFNs.

Key words: Community survey