Glottiphyllum is a genus of about 57 species of succulent subtropical plants of the family Aizoaceae. It is closely related to the Gibbaeum and Faucaria genera. The name comes from ancient Greek glottis “tongue” and phyllon “leaf”. The species are native to South Africa, specifically to the Cape Province and the Karoo desert. They grow in rocks and soils incorporating slate, sandstone and quartz. Rainfall in their native areas is between 125 and 500 mm, most of which falls in March and November. Glottiphyllum plants have thick, soft leaves arranged in pairs that are low to the ground and often graze the soil surface. They also have rhizomes. They sport yellow flowers with narrow petals in autumn and winter. The flowers are sometimes fragrant and around 5 cm in diameter. The species readily interbreed, making hybridization easy.

Glottiphyllum nelii, not to be confused with Glottiphyllum neilii, is synonymously known as Glottiphyllum pallens and Glottiphyllum pygmaeum, is a South African endemic species found in the Eastern Cape and Western Cape provinces. It grows characteristically keeled leaves positioned in two opposing rows with distinct soft, succulent edges. Flowering happens in autumn.