Pseudanthium

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A pseudanthium ( Greek "false flower" ) is a special form of an inflorescence in which several small, strongly reduced flowers are combined to form a new, flower-like structure, a false flower or overflower . Below the individual flowers is the flower base , the flower bed (Clinanthium, Phoranthium) of the individual flowers, which together form the flower basket (Calathium, Anthodium). These include bracts or bracts (phyllaria, involucral leaves), which can be free or fused. In their entirety, they are called the enveloping cup ( involucrum ; Latin: "envelope"). This involucre can contribute to the pseudanthium's visual function, e.g. B. with Cornus kousa or the golden thistle ( Carlina ).

Pseudanthia are an essential characteristic of the large flowering plant family of the daisy family (Asteraceae). In the largest subfamily, the Asteroideae , to which the daisy and the sunflower belong, mostly zygomorphic marginal flowers , mostly ray florets , represent the display device, while the tubular flowers , which are usually radially symmetrical, are in the center. The pseudo-flowered fruit associations of figs are also known , here the fleshy and jar- shaped flower base is formed into a syconium (hypanthodium) in which the flowers sit, related to the flat coenanthium of the Dorstenia .

  • Pseudanthium of the daisy ( Bellis perennis ) in rear view: The bracts form a plate-shaped involucre

  • Longitudinal section through a pseudanthium of Bellis perennis with recognizable single flowers

  • Pseudanthium of Dorstenia hildebrandtii with radial bracts

  • Pseudanthium of the Asiatic flower dogwood ( Cornus kousa ) with four petal-like bracts.

Pseudanthia occur in the following families.

See also

literature

  • Peter Leins, Claudia Erbar: blossom and fruit, morphology, history of development, phylogeny, function and ecology. 2nd, revised edition, Schweizerbart, Stuttgart 2008, ISBN 978-3-510-66046-9 .
  • Regine Classen-Bockhoff: Pattern analysis in pseudanthia. In: Plant Systematics and Evolution. 171 (1-4): 2005, 57-88, doi : 10.1007 / BF00940596 .
  • D. Sokoloff, PJ Rudall & M. Remizowa: Flower-like terminal structures in racemose inflorescences: a tool in morphogenetic and evolutionary research. In: Journal of Experimental Botany 57 (13): 2006, 3517-3530, doi : 10.1093 / jxb / erl126 .