Alstonia iwahigensisAlstonia iwahigensis is a tree in the dogbane family Apocynaceae.DescriptionAlstonia iwahigensis grows as a medium to large-sized tree up to tall, with a trunk diameter of up to. The bark is greyish, yellowish or dark brown. Its fragrant flowers feature a yellow or pinkish corolla.Distribution and habitatAlstonia iwahigensis is native to Borneo and Palawan. The species is found in forests and on hillsides from sea level to altitude.