Cyathium Inflorescence

Inflorescence varies among different plants, with the arrangement of flowers on the floral axis being the determining factor. There are three main types of inflorescence:

Racemose: Indeterminate or Indefinite

Cymose – Determinate or Definite

Mixed

Cyathium is a special type of cymose inflorescence.

Special types of cymose inflorescence

Cyathium Inflorescence Definition

A cyathium inflorescence is a type of flower cluster in which the individual flowers are densely packed together in a cup-shaped structure. The cyathium is the most common type of inflorescence found in the plant family Euphorbiaceae.

The Cyathium is a specialised pseudanthium or false flower which forms the inflorescence of plants, particularly within the genus of Euphorbia. It takes the form of a cup-shaped structure, with secretory glands on the margin or periphery of the cup. Inside the cup, female flowers are surrounded by great numbers of male flowers, creating the illusion of a single flower.

The axis of this type of inflorescence is suppressed, resulting in a convex receptacle. At the center of the receptacle is a long-stalked and naked female flower, with a tricarpellary gynoecium, which is surrounded by a large number of male flowers arranged in a scorpioid cyme.

The cyathium comprises:

Five bracteoles (rarely four)

The upper tips of the small bracts are free and form a cup-like involucre which covers the opening. This alternates with the united state.

Five nectary glands (1-10)

At times, these are fused.

One female flower

The ovary is extremely reduced and positioned in the centre, at the base of the involucre. It comprises an ovary on a short stem having a pistil. It is surrounded by -

Five Groups of Male Flowers

Each of the reduced male flowers at the base of each of the bracteoles has an extremely reduced single anther on the stem.

The flower-like features of Cyathia are marked by vibrant coloured nectar glands and usually by petal-like appendages to the nectar glands or the brightly coloured petal-like bracts found under the Cyathia. Sometimes, the Cyathia are solitary, while other times they are found in cymes, wherein the inflorescences are of the second order in the pseudumbels on the dichotomously branched stalks or in the simple cymes comprising one cyathium at the centre and two lateral.

Cyathium Inflorescence Example

The inflorescence of Cyathium can be observed in species of Euphorbia and Poinsettia.

Cyathium Inflorescence can be seen in Euphorbia species.

“Inflorescence of the Euphorbia Family: Cyathium”

The genus Euphorbia is incredibly diverse, with nearly 2000 species, and it is part of the even more diverse Euphorbiaceae family which includes close to 75 species. The poinsettia is a popular example of this genus, with its red, showy modified leaves which are often mistaken for petals, even though they are not part of true flowers.

Clusters of greenish, small and cup-shaped structures known as cyathia are actually inflorescences or flower clusters. The male flowers are inconspicuous and reduced to a single red stamen, while female flowers consist of a single ovary on the stalk. In poinsettia, the ovary is concealed inside the cyathium, but in other species the ovary projects out of the cyathium upon maturity.

The cyathium’s rim has numerous greenish nectar glands which appear attractive to the insect pollinators. The glands in some species are subtended by the petaloid appendages (petal-like bracts). Usually, the Poinsettias show only one greenish gland for each cyathium with the absence of petaloid appendages.

Frequently Asked Questions about Cyathium Inflorescence

Cyathium Inflorescence

Cyathium inflorescence is a type of flower cluster found in certain species of plants in the Euphorbiaceae family. It consists of a cup-like involucre that encloses a single female flower and several male flowers. The involucre is typically surrounded by several bracts and sepals. The female flower is usually smaller than the male flowers and is located at the center of the cluster.

A Cyathium inflorescence is a special type of cymose inflorescence, in which a cup-like cluster of modified leaves surrounds a female flower and many male flowers. It appears as a single flower.

Cyathium inflorescence can be seen in plants belonging to the Euphorbia genus.

The Poinsettia plant is known for its cyathium inflorescence.

An example of a cyathium inflorescence is the flower of the Euphorbia plant.

The species of Euphorbia exhibits cyathium inflorescence.

What is a Cyathium Inflorescence?

The family Euphorbiaceae displays cyathium inflorescence.

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