The name is derived from the Ancient Greek words λίθος (líthos) 'stone' and ὄψ (óps) 'face', referring to the stone-like appearance of the plants.

Individual Lithops consist of one or more pairs of bulbous, almost fused leaves opposite each other and hardly any stem.

Nearly a thousand individual populations are documented, each covering just a small area of dry grassland, veld, or bare rocky ground.

Lithops are popular house plants and many specialist succulent growers maintain collections.

In hotter climates, Lithops will have a summer dormancy when they should be kept mostly dry, and they may require some water in winter.

Commercial growers mix a mild fungicide or weak strength horticultural sulfur into the plant's water to prevent rotting.

Low light levels will make the plants highly susceptible to rotting and fungal infection.

[3] In the United Kingdom the following species have gained the Royal Horticultural Society's Award of Garden Merit:[4] Mr Keith Green was appointed International Cultivar Registration Authority for Lithops in 2013, and recognises over 100 registered cultivars.

Lithops can readily be pollinated by hand if two separate clones of a species flower at the same time, and seed will be ripe about 9 months later.

At least half of the species listed in the Red List of South African Plants are classified as endangered or threatened for various reasons, including poaching for the succulent horticultural trade, habitat degradation, and decreased or restricted range due to urban and agriculture expansion.

[12] The first scientific description of Lithops was made by botanist and artist William John Burchell, explorer of South Africa, although he called it Mesembryanthemum turbiniforme.

Several more Lithops were published as Mesembryanthemum species until in 1922 N E Brown started to split up the overly large genus on the basis of the capsules.

Brown, Gustav Schwantes, Kurt Dinter, Gert Nel, and Louisa Bolus continued to document Lithops from across southern Africa, but there was little consensus on the relationships between them, or even which populations should be grouped as species.

They studied and revised the genus, in 1988 publishing a definitive book (Lithops: Flowering Stones) describing the species, subspecies, and varieties which have been accepted ever since.

Some published changes since 2006 include: One study of non-coding chloroplast DNA (trnS-trnG intergenic spacer), nuclear ribosomal internal transcribed spacer (nrITS) sequences and AFLP data found that Lithops was not monophyletic since Dinteranthus, Schwantesia, and Lapidaria were involved.