Kadua coriacea of the Rubiaceae (coffee) family is a small shrub with leathery leaves that are elliptic to oblong in shape, 3 to 8 cm (1.2 to 3.1 in) long and 1.5 to 3 cm (0.6 to 1.2 in) wide. Flowers are arranged in clusters at the ends of the branches, a few flowers per cluster. The fleshy petals are fused into a tube 5 to 10 mm (0.2 to 0.4 in) long. The capsules, which split open to release dark brown seeds, are cup- to top-shaped, 4 to 7 mm (0.2 to 0.3 in) long and 3 to 4 mm (0.1 to 0.2 in) in diameter.