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Achenes (Cypselas) of the common dandelion with pappus
Strawberry achenes enlarged 4.25 times

With achene ( ancient Greek χαίνειν chainein , gape 'with alpha privative , ie "not gape") is a form of Nutlike in botany closing fruits called.

Achenes are seeded indehiscent fruits (not open at maturity), in which a thin , only a single adhesive point lederiges , tough, dry pericarp (only partly lignified pericarp) encloses tightly adjacent a single seed (Testa). Typical examples are the sunflower , but also the seeds of the strawberry (genus Fragaria ), here no pappus is formed for a flyable diaspore .

The anthocarpic achenes (angiocarp) (Diclesium, Pseudoanthecium, Cypsela) form a special form , in which parts of the flower cover or the flower base combine with the fruit to form a diaspore . It can be a pappus, but other, winged shapes can also be formed. The best known example of this is the common dandelion . If the fruit shell is prickly, chopped, then one speaks of "burdock" (Bur) as with the common pointed burdock ( Xanthium strumarium ). Others are e.g. B. Valven in dock ( Rumex spp.) And other forms such as an overgrown and winged calyx in Abronia spp. and an overgrown perianth in Pisonia umbellifera or Boerhavia intermedia .

In the case of the nut-like wing fruit, wing nut (Samara), often an achene, the pericarp has grown into wings.

In the case of collective fruits or fruit associations from several achenes one speaks of a collective achenes fruit (Etaerio, Achenecetum, Achenetum) z. B. in the strawberry or Ranunculus gmelinii or an achene fruit association (Achenosum, Achenoconum) z. B. in the paper mulberry tree ( Broussonetia papyrifera ). A special form is the sykonium of the false fruits of figs ( Ficus spp.), Here the achenes are arranged on the inside in a fleshy, hollow flower base.

The following distinction is also made:

  • Achene; lonely, from an upper , unilocular (with an ovary compartment) ovary (otherwise as above) z. B. plumbaginaceae (Plumbaginaceae)
  • Cypsela; in solitary, anthocarpic fruits with subordinate , unilocular ovaries . An additional layer forms here over the pericarp. (otherwise as above) z. B. Compositae (Asteraceae)

A Doppelachäne (cremocarp, mericarp) comes in umbellifers before (Apiaceae), it is a gap fruit . One example of this family of herbs that contain numerous herbs is parsley .

Similar are the utricle , in which the pericarp is thin and loose , puffy (inflated) and larger and often paper-like, and the caryopsis , in which the thin pericarp is fused with the semen .

Web links

Commons : Achenes  - collection of images, videos and audio files

Individual evidence

  1. ^ Michael G. Simpson: Plant Systematics. Academic Press, 2006, ISBN 978-0-12-644460-5 , p. 384.
  2. Juliana Marzinek, Orlando Cavalari De-Paula, Denise Maria Trombert Oliveira: Cypsela or achene? Refining terminology by considering anatomical and historical factors. In: Rev. bras. Bot. Vol. 31, No.3, São Paulo 2008, doi : 10.1590 / S0100-84042008000300018 .