A genus of trees and shrubs of which many are climbers using hooks. They have opposite or alternate, simple leaves without stipules. The flowers are small, inconspicuous, bisexual, regular, and usually borne in cymes. There are 4 or 5 sepals and 4 or 5 incurved petals, often enclosing the stamens. The ovary is superior with 2 or 3 locules with a single ovule. The fruit has a single wing on the upper end. There are 35 species, found mainly in Asia, but there is 1 species in Africa and another in Madagascar.
Subjects: Plant Sciences and Forestry.