Dimorphotheca is a southern African genus, belonging to the family Asteraceae, and is found in South Africa (Western and Northern Cape) and Namibia. It consists of 15 species. The genus name Dimorpotheca means fruits with two forms and is derived from Greek dis, meaning two, morphe, shape or form and theka, a fruit, referring to the different kinds of seeds produced by the ray and the disc florets in some species, where the fruits formed by the ray florets are wingless and stick-like and the fruits formed by the disc florets are flattened and 2-winged.

Dimorphotheca spectabilis, commonly known as Showy Rain Daisy in English or Bietou in Afrikaans and synonymously known as Castalis spectabilis or Dimorphotheca ecklonis, is a South African endemic flowering perennial found in the Gauteng, Limpopo, Mpumalanga and North West provinces. Dimorphotheca spectabilis is a showy perennial daisy (herb) with lance shaped, blue-green leaves and several erect stems arising from woody roots. The flowers, which are produced during spring, are solitary blue, purple or white tinged with purple ray flowers that surround dark purple or violet disc-flowers. Growing to around 30cm tall, Dimorphotheca spectabilis is a widespread daisy in the Grasslands that is a spectacular showy flowering specimen in the garden attracting birds and insects. Perfect for a sunny or part shade area.