Goniothalamus with c. 16 species is one of the largest genera of the family Annonaceae (mempisang in Malay) recorded in Peninsular Malaysia. One endemic species is Goniothalamus curtisii King which is distributed in Perak, Selangor, Negeri Sembilan, Kelantan, Terengganu, Pahang and Johor. This common species is always found in primary lowland to hill forests up to 1000 m altitude, and often grows by streams, on sandy or clay soils, on limestone or sandstone (Sinclair, 1955).
The slender trees of G. curtisii can grow to 10 m tall with many parts of the plant covered with dense brown hairs. The characteristic feature of this species is its large glossy leaf laminas (25−40 cm long) with numerous secondary veins and clearly distinct tertiary veins. Its pendent flowers have three leaf-like sepals and two whorls of three petals. The outer petals are yellowish tinged red and are thinly coriaceous with velutinous hairs. The inner petals are ovate in shape and have velutinous hairs adaxially. The stamens of G. curtisii have long pubescent apiculate connectives and the ovaries are densely covered with hairs. Fruit stalks are short and the fruits are pale green to yellowish, about 2 cm long with very short hairs. It has one hairy seed (Saunders, 2003).
Most Goniothalamus species are widely used in traditional medicine and G. curtisii has been reported as a treatment for diarrhea (Mat-Salleh & Latiff, 2002). In the 2006 IUCN Red List of Threatened Species, G. curtisii was assessed as Least Concern (LC) by the late K.M. Kochummen, botanist from Forest Research Institute Malaysia.