this work aimed to investigate the composition, abundance and some behavioral aspects of phytophagous species associated with "murici da praia", byrsonima sericea (malpighiaceae), in the national park of restinga de jurubatiba, rio de janeiro state, brazil. during 14 months, from april 2003 to may 2004, bimonthly surveys were conducted on 120 plants, while observations on b. sericea insects were made since november 2000. an overall of 45 associated insect species were found, being 20 exophytic lepidopteran caterpillars, 17 exophytic coleoptera, four leaf miners and four galling species. lius sp. (buprestidae), a leaf miner beetle, was the most abundant and frequent species, followed by the caterpillar gonioterma indecora (elachistidae). a comparison between lepidopteran caterpillars on b. sericea in the restinga and other byrsonima species of the cerrado vegetation showed low insect similarities between these and b. sericea, which also had the lowest species richness. both caterpillars and leaf miners abundance peaked between june and august, prior to the leaf flush, while the abundance of exophytic coleoptera immatures increased simultaneously with leaf production. possible explanations for the temporal distribution patterns of insects on b. sericea are discussed and a brief description of the ecological aspects is given for the main identified phytophagous insect species.