The cyathium, or ciato is a very shortened selvedge inflorescence, simulating a single flower, typical of the Euphorbias, where nectariferous glands with different shapes (elliptic, crescent, etc.) are placed on a cup-shaped receptacle (elliptical, crescent, etc.) and, inside stamens, each representing a single male flower, surrounding a single female flower represented by a syncarpal tricarpellar ovary with 3 styles and 6 stigmas.
Cyathium is a typical inflorescence of the genus Euphorbia (Euphorbiaceae) which simulates a single flower.
The cyathium is formed by:
– five or four sterile parts called bracts that form a cup-shaped envelope;
– a series of nectars sometimes fused together;
– a feminine flower positioned in the center of the base of the casing. The female flower is formed by an overgrown ovary;
– five or more male flowers surrounding the female flower. These flowers are formed practically only by the stamen.
Cyathia are often grouped in turn in inflorescences such as tops and umbels.