Although previously classified as Streptocarpus primulifolius ssp. formosus, Streptocarpus formosus was recognized as a separate species because of its distinctive flower colour and leaves. Streptocarpus formosus grows in three localities, all close together on the Pondoland, Eastern Cape and southern KwaZulu Natal border less than 20 km from the coast. Those growing in the Oribi Nature Reserve, KwaZulu Natal, have mauve infused corolla lobes (as in the species picture) whilst those growing in the Mtamvuna Nature Reserve (KwaZulu Natal/Eastern Cape border) and Mzamba Gorge (Eastern Cape) have the more commonly known pale mauve almost white corolla lobes. The Oribi gorge form is slightly less robust and smaller than the other forms. Flowers are large (70 – 105 mm long) with long flower stalks, and leaves are narrowly obovate (250 – 350 mm long and up to 50 mm wide).

This is an attractive species, with interesting flowers distinctly picoteed in the bud stage. The bright yellow deep in the throat and interesting markings, as well as an elegant shape, would seem to suit it well as a contributor to hybridizing programs. It is, however, a spare bloomer, seldom having more than one bloom per stalk with few stalks produced. These characteristics seem to be dominant in the first generation of hybrids, so it has not been a popular parent, at least until recently.

This is a variable species, and some different forms can be seen in the links below.

• A nice plant growing at Linnaeus Gardens, Sweden
• A cultivated plant of the pale form, growing at Kirstenbosch Botanical Gardens, South Africa
• A close view of a flower on a cultivated show plant
• A colony of the species growing on a rocky slope
• A close view of the flowers of a darker form
• A close front view of a paler flower, showing the yellow throat