The floral biology of 3 species of Clusia sect. Chlamydoclusia and 3 species of Clusia sect. Cordylandra from Central Amazonia was investigated. The flowers of both sexes offer resin as the reward for pollinating bees. The male flowers of the species of sect. Chlamydoclusia may additionally offer pollen. Principal pollinators observed were bees, mainly of the tribes Euglossini and Trigonini. In the male flowers of sect. Chlamydoclusia the pollen is kept separately from the floral resin, but in sect. Cordylandra it is mixed with the resin. The elongated connectives of the fertile stamens in sect. Chlamydoclusia secrete droplets of an oily fluid which probably serves as accessory pollenkitt. The stigmas of the pistils and pistillodes of flowers of sect. Cordylandra secrete an oily fluid; possible functions of this are discussed. C. renggerioides has male plants with two different floral morphs; pollen of both produced fertile seeds when used to pollinate female plants. The taxonomic significance of the different pollination strategies in Clusia and their evolution is discussed.