fruiting structure of fungi of the phylum Ascomycota (kingdom Fungi). It arises from vegetative filaments (hyphae) after sexual reproduction has been initiated. The ascocarp (in forms called apothecium, cleistothecium [cleistocarp], or perithecium) contain saclike structures (asci) that usually bear four to eight ascospores. Apothecia are stalked and either disklike, saucer-shaped, or cup-shaped with exposed asci. The largest known apothecium, produced by Geopyxis cacabus, has a stalk 1 metre (40 inches) high and a cup 50 centimetres (20 inches) across. Cleistothecia are spherical and must rupture or disintegrate to release their ascospores. Perithecia are globular or flask-shaped with an apical opening for discharge of ascospores.
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