Goniothalamus giganteus

Goniothalamus giganteus is a species of plant in the family Annonaceae. It is native to Malaya, Sumatra and Thailand. Bioactive compounds extracted from its bark have been reported to have cytotoxic activity in tests with cultured human cancer cells. It is a tree reaching 30 to 70 feet in height. It has light colored bark. Its leaves are leathery and oblong with shiny, dark green upper sides and paler, lightly hairy undersides. Its flower buds are yellow. Mature flowers are yellow and large, 3 to 5 inches long. Its sepals are hairy on both surfaces and 0.5 inches long. It has numerous stamens. Pollen is shed as permanent tetrads.