Cent.: Buch.-Ham. s.n., ann. 1802 (types of O. rostrata & O. ternifolia); Wall. 4065 (type of O. rostrata var. longicollis); SSW 7161 (fr.). East: Stainton 6657; TI 6304698 (fr.).
200-2600 m; Himalaya (Nepal Sikkim), Assam, Burma, Indo-China, Yunnan.