Mesembs is a common popular term used for succulent members of the family Aizoaceae, which are often placed in a separate family of their own, Mesembryanthemaceae. They are sometimes also referred to as vygies, fig-marigolds, ice plants, midday flowers, living stones or flowering stones. They display remarkable variation in leaf architecture, flower colour and form as well as fruit structure. Therefore these plants fascinate many plant lovers of all ages and have become popular amongst collectors of succulent plants. They make excellent pot plants. Didymaotus is a monotypic genus (only one species in the genus). The genus name is taken from the Greek word, didymos, meaning double, and aotus, meaning flower – the plant that bears two flowers. The specific epithet lapidiformis means stone-like. It is not easily seen as it blends in with the surrounding stones.

Didymaotus lapidiformis, commonly known as Spirit Stone or Stone Plant in English and Beeskloutjie in Afrikaans, is a rare and fascinating chunky succulent that looks like a Lithops on steroids or a smaller yet colourful Pleiospilos! It is endemic to South Africa and grows in the arid winter rainfall regions of the Tanqua Karoo, near Ceres, in the Western Cape.