The genus Searsia was named after Paul B. Sears (1891-1990) who was head of the Yale School of Botany. The Anacardiaceae family is widespread in warmer parts of the world with about 111 species of Searsia occurring in southern Africa. Most of the species grown in southern Africa, belonging to the genus Rhus, have been placed in Searsia.

Searsia gueinzii commonly known as Thorny Karee and synonymously known as Rhus crispa, Rhus gueinzii, Rhus gueinzii var. spinescens, Rhus simii, Rhus simii var. lydenburgensis and Rhus spinescens, is a South African indigenous shrub or small tree up to 3m tall. It is said to have medicinal properties and has hard red wood. It has spiny branches, shiny brown fruit and blue to grey-green leaves. From summer to autumn it bears small flowers.