Streptocarpus rexii is a South African plant in the Gloxinia and African Violet family of Gesneriaceae, and occurring widely from the southern Cape along the coastal hills, mountains, wooded ravines and valleys, and moist forests of the east coast, through Natal as far north as the Eastern Transvaal, up to an altitude of about 900 m. This genus of epiphytes and lithophytes, of about 130 species, is mainly African and Mascarene, with four vagrant species in Asia. Streptocarpus, as do other Old World Gesneriaceae, is unusual in that it displays anisocotylous or unequal growth, i.e. one cotyledon continues to grow after germination.