Shrubs or small trees, evergreen, glabrous; sap colorless. Stems leafy. Leaves alternate, short-petiolate; blade unlobed, leathery; margins entire or minutely denticulate. Inflorescences terminal on short branchlets, 1-flowered. Flowers: sepals 2, distinct; petals 4, yellow, obovate or obcuneate, with satin sheen from microscopic linear grooves; stamens many; pistil 1, 2-carpellate; ovary cylindric to long-conic, 1-locular; style absent; stigmas 2, obcompressed. Fruits capsular, cylindric, 2-valved, dehiscing from base along placentas. Seeds many, brown or black, obovoid, smooth, pale carunculate, aril absent. x = 28.
w North America.
Species 2 (2 in the flora).