Description from Flora of China
Cascabela Rafinesque; Plumeriopsis Rusby & Woodson.
Trees or much-branched shrubs, evergreen, erect, latex white. Leaves alternate, rather densely together on slender branchlets. Cymes terminal and leaf opposed. Calyx deeply divided, with many basal glands inside. Corolla yellow, funnelform, lobes overlapping to left, throat with 5, narrow, long-hairy scales. Stamens inserted in distal narrow part of corolla tube; filaments very short; anthers narrowly oblong, small, free from pistil head, cells not appendaged proximally; disc absent. Ovary 2-loculed, placenta prominent. Style filiform; pistil head disclike, thick, dilated, apex shortly 2-cleft. Drupes depressed globose; endocarp hard, woody or fleshy. Seeds 2 per locule, wingless, not comose, without endosperm; cotyledons suborbicular, fleshy, radicle short.
Eight species: tropical America, two species cultivated in China.