Wild durian (Cullenia exarillata) is a species of plant in the Malvaceae, a tall tree with smooth, greyish-white bark, peeling on older trees, a straight trunk, horizontal branches and often with a series of knob-like tubercles for flower and fruit attachment.
C. exarillata has young branches and the underside of the leaves is covered with golden brown peltate or shield-like scales. The leaves are single, alternate, glabrous, glossy green on the upper side and covered with silvery or orange peltate scales on the underside.
Hermaphroditic flowers are tubular and also covered with golden brown scales, 4-5 cm long and cream or reddish brown in color. Flowers have no petals, formed of tubular bracteoles and tubular calyxes, 5-lobed.
Fruit is round, 10-13 cm in diameter, covered with thorns and clustered along the branches. Many seeds, reddish brown, 4-5 cm long and 2-3 cm wide. The seeds are enclosed by a fleshy, whitish aril. The fruit splits open when ripe and dries to release the seeds.
Kingdom: Plantae
Phylum: Tracheophyta
Subphylum: Angiospermae
Class: Magnoliopsida
Order: Malvales
Family: Malvaceae
Subfamily: Helicteroideae
Tribe: Durioneae
Genus: Cullenia
Species: Cullenia exarillata