The tribe Calenduleae of the Compositae (Asteraceae) has a pronounced centre of diversity in South Africa, particularly in Cape Province. The largest genus, Osteospermum L., contains c.50 species in Africa and southwestern Arabia, including about 40 in Cape Province. Two new species are described here, both narrowly endemic in southwestern Cape Province. Osteospermum australe is confined to lowland coastal limestone areas in Bredasdorp district, whereas Osteospermum burttianum has a restricted distribution in the Langebergen mountains in Heidelberg district.
