Pollen-presenter

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Stenocarpus sinuatus, pollen presenters Stenocarpus sinuatus, pollen presenters.jpg
Stenocarpus sinuatus, pollen presenters

A pollen-presenter is an area on the tip of the style in flowers of plants of the family Proteaceae on which the anthers release their pollen prior to anthesis. To ensure pollination, the style grows during anthesis, sticking out the pollen-presenter prominently, and so ensuring that the pollen easily contacts the bodies of potential pollination vectors such as bees, birds and nectarivorous mammals. The systematic depositing of pollen on the tip of the style implies the plants have some strategy to avoid excessive self-pollination.

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<span class="mw-page-title-main">Pollination</span> Biological process occurring in plants

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<span class="mw-page-title-main">Self-pollination</span> Form of pollination

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Leucospermum is a genus of evergreen upright, sometimes creeping shrubs that is assigned to the Proteaceae, with currently forty-eight known species.

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<span class="mw-page-title-main">Anthesis</span>

Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period.

This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnifying lens. This page provides help in understanding the numerous other pages describing plants by their various taxa. The accompanying page—Plant morphology—provides an overview of the science of the external form of plants. There is also an alphabetical list: Glossary of botanical terms. In contrast, this page deals with botanical terms in a systematic manner, with some illustrations, and organized by plant anatomy and function in plant physiology.

<i>Mimetes hirtus</i> Species of plant from the family Proteaceae endemic to the southwest Western Cape, South Africa

Mimetes hirtus is an upright, evergreen shrub of 1½–2 m (5–6½ ft) high from the family Proteaceae. It has upright, overlapping, (broadly) lance-shaped leaves, without teeth, but with one thickened pointy tip. It has cylindric inflorescences topped by a pine apple-like tuft of pinkish-brownish, smaller and more or less horizontal leaves. The flowerheads are tightly enclosed by yellow, red-tipped bracts, only the 9–14 long red styles and the whitish silky tips of the perianth sticking out. It is primarily pollinated by the Cape sugarbird. It is an endemic species of the southwest of the Western Cape province of South Africa, and grows in wet zones at the base of south facing mountain slopes. Flower heads may be found from May to November, but peaks in July and August. The species has several vernacular names of which marsh pagoda seems to be used most.

<i>Xyris tennesseensis</i> Species of yelloweyed grass

Xyris tennesseensis is a rare species of flowering plant in the family Xyridaceae known by the common name Tennessee yellow-eyed grass. It is native to a small section of the Southeastern United States, including parts of the states of Alabama, Georgia, and Tennessee. A federally listed endangered species, it is threatened by the loss and degradation of its habitat.

<i>Leucospermum erubescens</i> Species of shrub in the family Proteaceae from South Africa

Leucospermum erubescens is an evergreen shrub of up to 2 m high, with hairless, lancet-shaped to oval leaves with three to seven teeth near the tip of 7–8½ cm long and 1–2 cm wide, slightly asymmetric, oval flower heads of 5–6½ cm in diameter, and usually with four to eight clustered near the end of the branches, with initially yellow flowers, that change to deep crimson, from which long styles stick out, giving the flowerhead as a whole the appearance of a pincushion. It is called orange flame pincushion in English and oranjevlamspeldekussing in Afrikaans. It can be found in South Africa. Flowers may be found between August and January.

<i>Leucospermum praemorsum</i> Shrub in the family Proteaceae from the Western Cape of South Africa

Leucospermum praemorsum is an evergreen shrub or small tree of up to 5 m (16 ft) high. It has hairless oblong to inverted lance-shaped leaves of 7–8 cm long and 1½–2 cm wide, tapering at their base to a stalk of up to 2 cm long, and cut-off at the tip with three to five teeth, and pale carmine, inverted cone-shaped flower heads. From the center of the flowers emerge long initially orange, later deep crimson styles that jointly give the impression of a pincushion. It is called Nardouw fountain-pincushion or Nardouw pincushion in English and Nardouwluisiesbos in Afrikaans. Flower heads can be found off and on throughout the year, particularly in older plants, with a peak between July and December. It is an endemic species that can only be found in part of the Western Cape province of South Africa.

<i>Leucospermum tottum</i> Shrub in the family Proteaceae from the Western Cape of South Africa

Leucospermum tottum is an upright, evergreen shrub of up to 1½ m high and 2 m (6 ft) in diameter from the Proteaceae. The oblong, mostly entire leaves with a bony tip are somewhat spreading and distant from each other, and so exposing the stem. It is called elegant pincushion or ribbon pincushion in English, and oranje-rooi speldekussing or vuurhoutjies in Afrikaans. Flowers can be found between September and January. The species naturally occurs in the Western Cape province of South Africa. Two different varieties are distinguished, which are genetically very close, but differ in the color, orientation and tube-length of the flowers, the volume and sugar content of the nectar. This is probably an adaptation to different pollinators.

<i>Leucospermum formosum</i> Shrub in the family Proteaceae from the Western Cape of South Africa

Leucospermum formosum is a large upright shrub of up to 3 m (9.8 ft) high, from the family Proteaceae. It grows from a single trunk and its branches are greyish felty. The softly felty leaves are lance-shaped to elliptic, 6+12–10 cm (2.6–3.9 in) long and 14–20 mm (0.55–0.79 in) wide. The flower heads are flattened and about 15 cm (5.9 in) across, and consist of bright yellow flowers from which long, styles emerge which are strongly clockwise bent just below the white, later pink thickened tip. From above, the heads look like turning wheels. It is called silver-leaf wheel-pincushion in English. It flowers during September and October. It is an endemic species of the Western Cape province of South Africa.

<i>Leucospermum arenarium</i> Species of srub in the family Proteaceae from the Western Cape province of South Africa

Leucospermum arenarium is a lax, evergreen shrub, with arching and drooping branches, that has been assigned to the family Proteaceae. It has loosely spaced, upright, greyish, narrowly egg-shaped to line-shaped leaves, mostly without teeth and flattened globe-shaped flower heads of 5–7 cm across, consisting of mostly creamy, seldom yellow flowers, that curve in the bud to the center of the head. From the center of the flowers emerge curved styles that jointly give the impression of a pincushion. The common name in English is Redelinghuys pincushion. It only occurs in a very small area in the Western Cape province of South Africa. It flowers between July and October. Unlike in related species the flowers are pollinated by hairy-footed gerbils and striped field mice.

<i>Protea pruinosa</i> Species of flowering plant in the family Proteaceae

Protea pruinosa, also known as frosted sugarbush or burnished protea, is a flowering shrub which belongs to the genus Protea within the botanical family Proteaceae. The plant is endemic to the southwestern Cape Region of South Africa.

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