Hesperantha

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Hesperantha
Hesperantha coccinea variety used as an ornamental plant.

Hesperantha coccinea variety used as an ornamental plant.

Systematics
Class : Bedecktsamer (Magnoliopsida)
Monocots
Order : Asparagales (Asparagales)
Family : Iris family (Iridaceae)
Subfamily : Crocoideae
Genre : Hesperantha
Scientific name
Hesperantha
Ker Gawl.

The Hesperantha are a plant genus in the family of the Iridaceae (Iridaceae). The genus contains about 79 to 91 species . The generic name Hesperantha is derived from the ancient Greek words ἑσπέρα hespera for "evening" and ἄνθος ánthos for "blossom" or "flower", so "evening blossom", because in many species the flowers open in the evening.

description

Hesperantha species grow as deciduous, perennial, herbaceous plants . These geophytes form small bulbs with hard coverings (“tunics”) as persistence organs; only Hesperantha coccinea forms rhizomes instead of tubers . Most species reach a maximum height of 15 to 20 cm.

There are leaves in winter or summer depending on the rainy season of the home area. The basal, upright to spreading leaves are simple, flat and parallel-veined; the shape is variable. The leaf margin is smooth.

The terminal, spiked inflorescences are slender to compact. There are bracts available. It is noticeable that the flowers of all species have a relatively similar structure and look pretty much the same apart from their color. The relatively small flowers are hermaphroditic, threefold and usually radial symmetry to weakly zygomorphic . There are two circles, each with three usually 10 to 25 mm, rarely up to 37 mm long bracts present, which are almost identically shaped in both circles. The bracts are fused tubular. The free area of ​​the bracts is spread out in a star shape. The colors of the bracts range from white to cream to yellow and from red to pink and purple to blue, sometimes with darker markings. There is only one circle with three fertile stamens . Three carpels have become an under constant ovary grown. The style divides above the bloom tube into three long branches. In many species, the flowers do not open until late afternoon or early evening (hence the botanical name) and close at dawn, their bracts are white to cream-colored and in many of the night-blooming species in winter rain areas the flowers have a strong scent.

The triple capsule fruits contain many seeds. The small seeds are light to dark brown.

distribution

Hesperantha species are found only in sub- Saharan Africa. Their distribution area extends from Namaqualand to the Eastern Cape , Natal and Transvaal . The center of biodiversity is in the Capensis , the area of ​​the North and West Cape . 42 species thrive in areas with winter rains and 37 species thrive in areas with summer rains. Four species are native to tropical Africa.

Due to the abundant seed production and good germination results, they tend to grow wild and are invasive plants in some areas of the world .

Hesperantha baurii
Section of an inflorescence of a Hesperantha coccinea variety. The three stamens and the three long stylus branches are clearly visible.
Blossom of the Hesperantha coccinea variety 'Viscountess Byng'
Hesperantha coccinea - variety 'Alba'
Hesperantha falcata

Systematics

The genus Hesperantha belongs to the tribe Croceae (Syn .: Ixieae) in the subfamily of the Crocoideae within the family of the Iris family (Iridaceae). The genus Hesperantha was first published in 1805 by John Bellenden Ker Gawler in Annals of Botany , 1, 224. A synonym for Hesperantha L. is: Schizostylis Backh. & Harv.

In Novon , Volume 6, No. 3, 1996, Goldblatt & Manning placed Schizostylis coccinea as Hesperantha coccinea in the genus Hesperantha ; a monotypic genus Schizostylis could not be maintained.

The genus Hesperantha is divided into three sections (Goldblatt 2003):

Section Concentrica Goldblatt : With about 62 species.
Section Hesperantha Goldblatt : With eight species.
Section Radiata Goldblatt : With nine species.

There are about 79 to 91 species of Hesperantha :

use

Some varieties are used as ornamental plants .

literature

  • Peter Goldblatt: A synoptic review of the African genus Hesperantha (Iridaceae: Crocoideae). , in Ann. Missouri Bot. Gard., 90, 2003, pp. 390-443: Online. (PDF; 498 kB)
  • J. Gathe: Hesperantha in the Western Australian Flora Online : Description, 2008.
  • Peter Goldblatt, Ingrid Nänni, Peter Bernhardt & John C. Manning: Floral Biology Of Hesperantha (Iridaceae: Crocoideae): How Minor Shifts In Floral Presentation Change The Pollination System. in ANN. MISSOURI BOT. GARD. , 91, 2004, pp. 186-206: Online. (PDF; 242 kB)
  • John C. Manning, Peter Goldblatt & D. Snijman: The color encyclopedia of Cape bulbs. , Timber Press, USA, 2002.
  • Peter Goldblatt & John C. Manning: The Iris Family: Natural History and Classification. , Timber Press, Portland, 2008.
  • Entry with the pacific bulbsociety.

Individual evidence

  1. ↑ a b Rafaël Govaerts (Ed.): Hesperantha. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved July 23, 2018.
  2. ^ A b Hesperantha in Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
  3. ↑ Species list from Conservatoire et Jardin botaniques & South African National Biodiversity Institute - Genéve.

Web links

Commons : Hesperantha  - Collection of images, videos and audio files