See text for accepted species Mesembryanthemum is a genus of flowering plants in the family Aizoaceae, indigenous to southern Africa.

[3] In South Africa, Mesembryanthemums are known as "vygies" (from Afrikaans "vy"), although that term refers to many plants in the family Aizoaceae.

Species formerly placed in Mesembryanthemum have been transferred to other genera, such as Cleretum and Carpobrotus, although sources differ.

In 1719, with the discovery that some species flowered at night, Johann Jacob Dillenius changed the spelling to Mesembryanthemum ("flower with the pistil in the center"[4]), rederiving the first part of the word from Greek μεσος ("middle") and ἔμβρυον ("pistil" or "embryo").

[citation needed] Some Mesembryanthemum species are thought to be hallucinogenic plants, like related Aizoaceae,[6] and as such may be subject to legal restrictions (e.g., Louisiana State Act 159).