Mackaya is a genus of flowering plants in the family Acanthaceae, disjunctly distributed in Brazil, South Africa, and the eastern Himalayas, Southeast Asia and China. It is sister to Asystasia.

Mackaya bella is a beautiful shrub or small tree with slender branches bearing dark green leaves. The leaves are simple and oppositely arranged. Small, hairy pockets are often found in the axil of the veins. It has beautiful, large and attractive mauve to white flowers in terminal racemes usually marked with fine purple-pink lines. The genus Mackaya was named after James Townsend Mackay, author of Flora Hibernica. There is only one species in the genus Mackaya. The genus Mackaya was once included in the genus Asystasia. Its specific name bella means “beautiful”, a tribute to its large bell shaped flowers. The forest bell bush occurs naturally in the Eastern Cape, Kwa-Zulu Natal, Swaziland and Northern Province in evergreen forest, often along the edges of stream. This plant occurs nowhere else in the world except in Southern Africa which means is endemic to this region. Mackaya bella makes a stunning display if planted in a pot and can also serve for screening in a semi-shade area. The river bell is a desirable garden plant, which thrives in shade but flowers best with more sun, although this may cause leaves to yellow. The wood was once used to kindle fire by friction.