Английская Википедия:Barberetta

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Barberetta is a genus of herbaceous perennial plants in the family Haemodoraceae. It contains only one known species, Barberetta aurea.[1]

Description

Barberetta aurea grows to up to Шаблон:Cvt high from a tuberous rootstock and develops about 3 leaves that are arranged like a fan, flattened sideways and so creating a left and right surface rather than an upper and lower surface. The leaves lack a leafstalk, are lance-shaped in outline, hairless, up to Шаблон:Cvt long and Шаблон:Cvt wide at midlength, narrowing gradually to the foot and the tip, and have five distinct vertical ribs and several finer ribs in between. The stem is weak, Шаблон:Cvt long, with some hairs towards the top, and carries its many flowers in a simple raceme, of Шаблон:Cvt long. The stalks of the individual flower are inclined upwards, the lower flower stalks are Шаблон:Cvt long. Wrapped around the foot of each flower stalk is a persistent lance-shaped bract of up to Шаблон:Cvt long. The star-symmetric perianth consists of six tepals of about Шаблон:Cvt long and Шаблон:Cvt wide, that are yolk yellow when fresh and bright orange when dry. The upper three tepals have an orange spot at their base. The stamens are approximately Шаблон:Cvt long. The two upper filaments ascend and slightly diverge, while the lower filament diverges strongly in the direction opposite to the style. The filaments are yellow and carry very short, orange, elliptic anthers. The ovary is green in colour and about Шаблон:Cvt in diameter and contains one ovule of approximately Шаблон:Cvt in diameter. The ovary is a yellow style of Шаблон:Cvtm long that is strongly bent sideways and carries an orange coloured stigma. The ovary develops into an initially yellow, later blackish half egg-shaped capsule of about Шаблон:Cvt across that contains a single orange finely papillous seed of around Шаблон:Cvt. The sap of this plant stains paper red.[2] Barberetta aurea has a base chromosome count of 15 (n=15).[3][4] Small corms grow in the axils of the bracts that are responsible for vegetative reproduction.[5]

Taxonomy

Barberetta aurea was described in 1868 by William Henry Harvey.[6][7] The genus Barberetta is named in recognition of a Mrs. Barber who collected this plant for science.[2][8] Aurea is a Latin word meaning "golden".

Comparison of homologous DNA has increased the insight in the phylogenetic relationships between the genera in the Haemodoroideae subfamily. The following tree represents those insights.[9] Шаблон:Clade

Distribution, ecology and conservation

Barberetta aurea is endemic to South Africa (Eastern Cape province and KwaZulu-Natal). Like in the species of the closely related genus Wachendorfia, two types of individuals occur, plants with only flowers with the style curved to the left and plants with flowers with the style curved to the right, and these are both present within the same populations. This so-called floral enantiomorphy is thought to be a mechanism to increase outcrossing and so boost genetic diversity.[10] The species grows in moist and shaded locations.[2] Barberetta aurea is considered a least-concern species.[11]

References

Шаблон:Reflist

Шаблон:Taxonbar