Summary
This paper presents the basic characteristic of the floral biology of Annona sericea Dun. Observations were based on five adult trees located on the INPA Campus in Manaus, AM. The flowers of Annona sericea Dun. are cantharophilous with the temperature of the flower rising to 6°C above of nighttime temperature. Insect visitors observed were beetles of the family Chrysomelidae (likely pollinators) and flies of the family Sciaridae (occasional pollinators). The beetles feed on the internal parts of the petals and also mate inside the flowers. The synchronous shedding of the stigmas and subsequent dehiscence of the anthers on any given plant precludes the possibility of self-pollination both at the level of the flower and individual tree however the species is self-compatible. Pollen fertility is 96%, however the natural fruit-set is very low.