Description:

• Annual to perennial succulents, ranging from minute to compact and tufted to prostrate to decumbent; herbs, dwarfshrubs, subshrubs or shrubs, rarely spiny
• Leaves opposite, rarely alternate, simple, free at base to almost completely united into single, conical to ± spherical bodies, often sheathing stem, flat to 3-angled to cylindric, all similar (plant homophyllous) or different types of leaf pairs present (plant heterophyllous, e.g. Mitrophyllum Group), members of a leaf pair similar (plant isophyllous) or dissimilar (plant anisophyllous), surface heterocellular (with cells of different sizes) or homocellular (cells of similar size), ephemeral to persistent, with or without bladder cells, sometimes tuberculate or punctate; stipules 0
• Flowers bisexual, regular, in cymose inflorescences, sometimes representing ± entire plant, to solitary
• Calyx 4-6-lobed, sometimes forming a short tube above ovary
• Corolla of many ± linear petals of staminodial origin, either free or shortly connate at base
• Stamens many, often surrounded by few to many filamentous staminodes
• Nectary either koilomorphic: represented by usually 4 or 5 shell-shaped depressions (in Mesembryanthemoideae), or lophomorphic: raised into a crested ring, continuous or broken into ± 5 crested glands (in Ruschioideae)
• Ovary inferior to half-inferior (in Mesembryanthemoideae), (3, 4)5(-25)-locular; placentas ranging from axile through basal to parietal; ovules usually many; style 0; stigmas usually as many as locules, subulate to filiform, sometimes fused at base, sometimes plumose
• Fruit a loculicidal capsule, splitting open when dry or mostly when wetted by means of hygroscopic expanding keels, rarely schizocarpic with winged or nut-like mericarps, or fleshy and indehiscent; valves with or without wings, expanding keels parallel to divergent, locules open or with covering membranes, closing bodies blocking distal exits of locules present or 0
• Seeds ± reniform, glossy to rugose or papillate and rough, black to brown to pale cream; embryo curved around perisperm

Nomenclature:

• Mesembryanthemaceae
  • Schwantes: 1 (1957)
  • Friedrich: 1 (1970)
  • Herre: 1 (1971)
  • Hartmann: 313 (1988)
  • Hartmann: 75 (1991a)
  • Hartmann: 95 (1991b)
  • Hartmann: 37 (1993)
  • Chesselet et al.: 197 (1995)
  • Hammer: 195 (1995)
  • Smith et al.: 1 (1998)

Distribution & Notes:

• Global: Genera ± 123, species ± 1 680, mostly in the southwestern parts of the African continent, from ± 16° N in Angola down to the Western Cape Province, extending well into the east over the central plateau of South Africa and reaching into Zimbabwe and Botswana
• Southern Africa: Genera ± 122, species ± 1 662
• Notes:
  • Outside this core area, several species of Delosperma are found from N Tanzania up to the Yemen and also in the Arabian Peninsula and Madagascar
  • A few species of Mesembryanthemum occur around the Mediterranean Sea, and most species of the genus Disphyma are found in Australia, New Zealand and the adjacent islands
  • The genus Sarcozona and some species of Carpobrotus are restricted to Australia, but species of Ruschia and Lampranthus may not be indigenous to Australasia
  • It is also not clear whether species of Malephora and Carpobrotus are recent introductions to South America, but the populations of Carpobrotus found along the west coast of North America were certainly introduced by man.

References:

• BITTRICH, V. 1986. Untersuchungen zu Merkmalsbestand, Gliederung und Abgrenzung der Unterfamilie Mesembryanthemoideae (Mesembryanthemaceae Fenzl). Mitteilungen aus dem Institut für Allgemeine Botanik. Hamburg 21
• BITTRICH, V. & HARTMANN, H.E.K. 1988. The Aizoaceae - a new approach. Botanical Journal of the Linnean Society 97
• CHESSELET, P., MÖSSMER, M. & SMITH, G.F. 1995. Research priorities in the succulent plant family Mesembryanthemaceae Fenzl. South African Journal of Science 91
• FRIEDRICH, H.C. 1970. Aizoaceae. Prodromus einer Flora von Südwestafrika 27
• GERBAULET, M. 1995. Phyllobolus N.E.Br. emend. Bittrich (Aizoaceae): A reassessment of generic boundaries. Botanische Jahrbücher 117
• GERBAULET, M. 1996a. Revision of the genus Aridaria N.E.Br. (Aizoaceae) Botanische Jahrbücher 118
• GERBAULET, M. 1996b. Revision of the genus Prenia N.E.Br. (Aizoaceae). Botanische Jahrbücher 118
• GERBAULET, M. 1996c. Revision of the genus Sceletium N.E.Br. (Aizoaceae) Botanische Jahrbücher 118
• GERBAULET, M. 1997. Revision of the genus Phyllobolus N.E.Br. (Aizoaceae). Botanische Jahrbücher 119
• HAMMER, S.A. 1995. Mastering the art of growing mesembs. Cactus and Succulent Journal (US) 67
• HARTMANN, H.E.K. 1988. Fruit types in Mesembryanthema. Beiträge zur Biologie der Pflanzen 63
• HARTMANN, H.E.K. 1991a. Mesembryanthema. Contributions from the Bolus Herbarium 13
• HARTMANN, H.E.K. 1991b. Keys to the genera of Mesembryanthema. South African Journal of Botany 57
• HARTMANN, H.E.K. 1993. Aizoaceae. In K. Kubitzki, J.G. Rohwer & V. Bittrich, The families and genera of vascular plants - Dicotyledons 2. Springer-Verlag, Berlin
• HARTMANN, H.E.K. 1998a. A Letter to the MSG. Mesemb Study Group Bulletin 2
• HERRE, H. 1971. The genera of the Mesembryanthemaceae. Tafelberg, Cape Town
• HERRE, H. & VOLK, O.H. 1948. Mesembryanthemaceae Herre et Volk, familia nova. Sukkulentenkunde 2
• KLAK, C. & LINDER, H.P. 1998. Systematics of Psilocaulon N.E.Br. and Caulipsolon Klak gen. nov. (Mesembryanthemoideae, Aizoaceae). Botanische Jahrbücher 120
• SCHWANTES, G. 1957. Flowering stones and mid-day flowers. Ernest Benn Limited, London
• SMITH, G.F., CHESSELET, P., VAN JAARSVELD, E.J., HARTMANN, H., HAMMER, S., VAN WYK, B-.E., BURGOYNE, P., KLAK, C. & KURZWEIL, H. 1998. Mesembs of the world. Briza, Pretoria
• WALLACE, R.S. 1998. Systematic implications of evolutionary relationships within the Aizoaceae s.l. Proceedings: Programme & Abstracts of the 25th Congress of the International Organization for Succulent Plant Study. 31 August to 4 September 1998

Resources:

• Classification of Mesembryanthemaceae
• Key to Mesembryanthemaceae genera (Key 1) - based mainly on fruit and flower characters
• Key to Mesembryanthemaceae genera (Key 2) - based mainly on vegetative characters

• Guide to Mesembryanthemaceae Fruit Types
• Key to Mesembryanthemaceae Fruit Types

• Mesembryanthemaceae genera: