Gorteria

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Gorteria
Gorteria diffusa Hantham 02.jpg
Gorteria diffusa
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Asterales
Family: Asteraceae
Subfamily: Vernonioideae
Tribe: Arctotideae
Subtribe: Gorteriinae
Genus: Gorteria
L.
Type species
Gorteria personata
L.
Synonyms [1]
  • Ictinus
  • Personaria

Gorteria is a genus of small annual herbaceous plants or shrubs, with 8 known species, that is assigned to the daisy family (Compositae or Asteraceae). Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and are surrounded by an involucre, consisting of in this case several whorls of bracts, which are merged at their base. In Gorteria, the centre of the head is taken by relatively few bisexual and sometimes also male, yellow to orange disc florets, and is surrounded by one complete whorl of 5–14 infertile cream to dark orange ray florets, sometimes with a few ray florets nearer to the centre. None, some or all of them may have darker spots at their base. The fruits remain attached to their common base when ripe, and it is the entire head that breaks free from the plant. One or few seeds germinate inside the flower head which can be found at the foot of plants during their first year. The species flower between August and October, except for G. warmbadica that blooms mostly in May and June. The species of the genus Gorteria can be found in Namibia and South Africa. [2]

Contents

Description

Gorteria personata Gorteria personata - Flickr - Kevin Thiele.jpg
Gorteria personata

Five of the species assigned to Gorteria are always annuals, two always shrublets (G. alienata and G. integrifolia), and one species (G. diffusa) is mostly annual, but populations near the coast in Namaqualand tend to survive and become woody in their second year. The stems are cylindrical (or terete) with 1–2 mm (0.039–0.079 in) long, stiff white hairs, rarely reddish or blackish at their foot, striped along their lengths, and sometimes with short soft hair as well. The alternately set leaves lack a stalk, have margins rolled downward and inward. The upper surface is sparsely to densely set with ½–2 mm (0.02-0.08 in) long stiff white hairs, while the lower surface is whitish felty hairy except on the midvein. The flower heads can be found on their own at the end of the branches, and are enveloped in an involucre, whose bracts are merged at their base only, with short, soft, silky white hairs and long, stiff white hairs with striping along their lengths. These involucres become woody with age, and the entire flower heads detach from the mother plant with the fruits (or cypselas) inside them. Later one new plant emerges (or sometimes up to five) from it. The common base of the florets (called the receptacle) does not have receptacular bracts (or paleas) at the foot of each floret. There are between five and fourteen infertile ray florets that have a base color that ranges between cream and dark orange. At the base there may be darker spots, sometimes jointly creating a ring, but sometimes only present on two or three of the ray florets. The underside has mostly a darker, less clear color and there are some short, striped hairs. The fertile yellow to orange disc florets are somewhat bilateral symmetrical (or zygomorph), deeply incised to form five lobes and have some hairs and glandular hairs. Some set seed, but most of them are functionally male. The anthers do not have tail extensions. [2]

A very particular character for Gorteria is that plants in their first year have an old flower head at their foot, because the cypselas do not part from the flower head when ripe, but germinate remaining in the flower head. Furthermore, the species of Gorteria share spine-like hairs on the corollas of both ray- and disc florets, the bracts of the involucre merged only at their foot, and crystals below the skin of the outer seed coat. All these characters are absent in its near relatives. [2]

Taxonomy

Carl Linnaeus, famous for his introduction of the binominal nomenclature, erected the genus Gorteria, in part II of the 10th edition of his Systema Naturae published in 1759, with the description of the type species Gorteria personata. [3] Linnaeus' circumscription of the genus was much wider than today, since he included species that now are in several other genera of the Gorteriinae, such as G. squarrosa (= Cullumia squarrosa ) in 1760, Gorteria rigens (= Gazania rigens ) and G. fruticosa (= Berkheya barbata ), both in 1763. Carl Peter Thunberg in 1798 reviewed Gorteria and considered the interlocked margins (or connation) of the involucral bracts diagnostic for the genus, but this is in fact common to the entire subtribe Gorteriinae. He distinguished ten herbaceous species and two woody, seven including G. diffusa and G. integrifolia new to science. In 1818, French botanist Henri Cassini described the new genus Ictinus with type species piloselloides, but in 1824 reassigned it to Gorteria, making the new combination G. piloselloides. In 1820, Cassini erected the genus Hirpicium with type species H. echinulatum. This however is an illegitimate name, since the type specimen is identical to that used by Thunberg to base Oedera alienata on in 1792, and the correct name would be Hirpicium alienatum (= G. alienata). In 1797, Jean-Baptiste Lamarck erected the genus Personaria, and in 1816, Jean Louis Marie Poiret reassigned Personaria personata to Gorteria. In 1832, German botanist Christian Friedrich Lessing restricted Gorteria. In 1838, Augustin Pyramus de Candolle described three further species: G. affinis, G. calendulacea and G. corymbosa. In 1959 and 1973, Helmuth Roessler distinguished two subspecies in G. personata, subsp. personata and subsp. gracilis, and three subspecies in G. diffusa, subsp. diffusa, subsp. calendulacea and subsp. parviligulosa. Only in 2014, Frida Stångberg and Arne Anderberg reassigned Hirpicium alienatum and H. integrifolium to Gorteria, and clarified the relationship between the taxa within Gorteria. [2] The genus was named in honour of the Dutch physicians and botanists Johannes de Gorter and his son David de Gorter.

Phylogeny

The tribe Arctotideae consists of the subtribes Arctotidinae and Gorteriinae. The Gorteriinae contain two groups, one comprising Berkheya , Cullumia , Cuspidia , Didelta and Heterorhachis , the other one Gorteria and its close relatives of the genera Gazania and Hirpicium . Recent comparison of homologous genes has seriously upset the delineation of the species within Gorteria and prompted the reassignment of Hirpicium alienatum and H. integrifolium to Gorteria. According to this study, the species and their relationships are as expressed in the following tree. [2]

genus Gorteria

G. piloselloides

G. integrifolia

G. alienata

G. personata

G. diffusa

G. warmbadica

G. corymbosa

G. parviligulosa

Reassigned species

The species that were originally described as, or moved to Gorteria, which since have been reassigned include the following: [2]

Distribution

Representatives of the genus Gorteria can be found in the !Karas Region of Namibia, the Northern Cape and Western Cape provinces, and a few observations in the west of the Eastern Cape of South Africa. [2]

Related Research Articles

<i>Gazania</i> Genus of flowering plants

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<i>Gazania linearis</i> Species of flowering plant

Gazania linearis is a species of flowering plant in the family Asteraceae, with thin linear leaves, native to South Africa.

<i>Gazania rigens</i> Perennial plant in the daisy family from South Africa

Gazania rigens, sometimes called treasure flower, is a species of flowering plant in the family Asteraceae, native to coastal areas of southern Africa. It is naturalised elsewhere and is widely cultivated as an ornamental plant.

<i>Didelta</i> Plant genus in the Asteraceae from Southern Africa

Didelta is a genus of shrubs of up to 1 or 2 meter high, with two known species in the daisy family. Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and are surrounded by an involucre, consisting of in this case two whorls of bracts, which are almost free from each other. The 3–5 outer bracts are protruding and triangular in shape, the inner about twice as many are lance-shaped and ascending. In Didelta, the centre of the head is taken by 3–5 clusters of bisexual yolk yellow disc florets, sometimes divided from each other by male disc florets, and is surrounded by one complete whorl of infertile yolk yellow ray florets. The common base of the flowerhead swells around the developing fruitlets, become woody and breaks into segments when ripe. The fruitlets germinate within this woody encasing. The species of the genus Didelta can be found in Namibia and South Africa. The genus is called salad thistle in English and slaaibos in Afrikaans.

<i>Berkheya</i> Genus of flowering plants

Berkheya is a genus of flowering plants in the family Asteraceae. It is distributed in tropical Africa, especially in southern regions. Of about 75 species, 71 can be found in South Africa.

<i>Corymbium</i> Genus of perennial plants in the family Asteraceae from South Africa

Corymbium is a genus of flowering plants in the daisy family comprising nine species. It is the only genus in the subfamily Corymbioideae and the tribe Corymbieae. The species have leaves with parallel veins, strongly reminiscent of monocots, in a rosette and compounded inflorescences may be compact or loosely composed racemes, panicles or corymbs. Remarkable for species in the daisy family, each flower head contains just one, bisexual, mauve, pink or white disc floret within a sheath consisting of just two large involucral bracts. The species are all endemic to the Cape Floristic Region of South Africa, where they are known as plampers.

<i>Gazania krebsiana</i> Species of flowering plant

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<i>Gorteria diffusa</i> Annual plant in the daisy family from South Africa

Gorteria diffusa is a highly variable, small annual herbaceous plant or rarely a shrublet that is assigned to the daisy family. Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and are surrounded by an involucre, consisting of in this case several whorls of bracts, which are merged at their base. In G. diffusa, the centre of the head is taken by relatively few male and bisexual yellow to orange disc florets, and is surrounded by one complete whorl of 5–14 infertile cream to dark orange ray florets, sometimes with a few ray florets nearer to the centre. None, some or all of them may have darker spots at their base. The fruits remain attached to their common base when ripe, and it is the entire head that breaks free from the plant. One or few seeds germinate inside the flower head which can be found at the foot of plants during their first year. The species flowers between August and October. It is called beetle daisy in English and katoog in Afrikaans. It can be found in Namibia and South Africa.

<i>Felicia fruticosa</i> A shrublet in the daisy family from South Africa

Felicia fruticosa is a strongly branching shrub of up to 1.3 metres high that is assigned to the family Asteraceae with flower heads consisting of about twenty purple to white ray florets encircling many yellow disc florets, and small flat, entire and hairless leathery leaves. Two subspecies are recognized. Felicia fruticosa subsp. brevipedunculata, from the Limpopo Province of South Africa is up to 1.3 metres tall and has longer leaves of 2.5 centimetres (0.98 in) long and 2 millimetres (0.079 in) wide and nearly seated pale violet to white flower heads. Felicia fruticosa subsp. fruticosa, from the Western Cape province of South Africa, is no more than 1 m and has shorter leaves of 1.25 centimetres (0.49 in) long and 2.5 millimetres (0.098 in) wide with flower heads on largely leafless, about 2.5 centimetres (0.98 in) long stems. It is sometimes called bosastertjie in Afrikaans. In the wild, flower occurs from August till October.

<i>Felicia amoena</i> A perennial or biennial plant in the daisy family from South Africa

Felicia amoena is a variably hairy, sometimes glandular, biennial or perennial plant, of about 25 cm (10 in) high, that is assigned to the family Asteraceae. It is somewhat woody at its base, roots at the nodes if these contact the soil, and has ascending branches. The leaves are oppositely arranged along the stems at and just above a branching fork, further up the leaves alternate. The flower heads sit individually on up to 12 cm long stalks. They are 2–3 cm in diameter and consist of about twelve to twenty five heavenly blue ray florets that surround many yellow disc florets. Three subspecies have been recognised, that differ in width of the leaves and the involucral bracts, the size of the heads and number of ray florets and in having glandular hairs. These can be found in coastal sands and inland areas in the Western Cape and Eastern Cape provinces of South Africa. Flower heads can be found from June till October.

<i>Felicia bellidioides</i> A perennial plant in the daisy family from South Africa

Felicia bellidioides is a perennial plant of up to about 25 cm (10 in) high, that is assigned to the family Asteraceae. Most of the narrowly inverted egg-shaped leaves are silky hairy and in a basal rosette with no or few very narrow bracts on the stalk in the subspecies bellidioides. In the subspecies foliosa, the narrower leaves are not silky hairy but variously bristly and glandular, with more and larger bracts on the inflorescence stalk. The flowerheads sit individually on top of a long peduncle and consist of an involucre with only two worls of bracts, about twenty purplish blue ray florets, surrounding many yellow disc florets. It occurs in the Western Cape province of South Africa.

<i>Felicia bergeriana</i> A annual plant in the daisy family from South Africa

Felicia bergeriana is a richly branching, hairy annual plant of up to 25 cm (10 in) high that is assigned to the family Asteraceae. It has opposite leaves and flower heads set individually on up to 8 cm long stalks, that consist of an involucre of about 12 cm diameter with two whorls of bracts, about twelve blue ray florets surrounding more yellow disc florets. It is sometimes called kingfisher daisy in English. It can be found in the Northern and Western Cape provinces of South Africa. It is sometimes cultivated as an ornamental.

Felicia clavipilosa is an upright, richly branched shrub of up to 60 cm (2 ft) high, that is assigned to the family Asteraceae. It has alternately arranged leaves, and flower heads with 3–4 whorls of involucral bracts with many yellow disc florets in the centre. Very characteristic for the species are the short club-shaped hairs on its fruits. There are two subspecies. Subsp. clavipilosa has narrowly lance-shaped entire leaves with one vein and pale mauve ray florets. Subspecies transvaalensis has lance-shaped leaves with one or three veins and white ray florets. The species occurs in southern Africa, with subsp. clavipilosa having a western distribution in Zambia, Zimbabwe, Namibia, Botswana and South Africa, and subsp. transvaalensis restricted to the east, from Zimbabwe, through Botswana to South Africa. The subspecies transvaalensis is sometimes called pokkiesblom in Afrikaans.

<i>Felicia tenella</i> A annual or biennial plant in the daisy family from South Africa

Felicia tenella is an annual, sometimes biennial, herbaceous plant that may be slightly woody at its base, of 5–70 cm tall, that is assigned to the family Asteraceae. The species is very variable in size and hairiness. Its branches may be erect or ascending, and the leaves are narrowly line-shaped, 2–5 cm long and about 1 mm (0.04 in) wide. The leaves have a callous tip, lack visible nerves, and are mostly rigidly ciliate. The flower heads sit individually at the tip of stalks, have an involucre of three whorls of bracts, and about thirty light blue ray florets surrounding many yellow disc florets. Four subspecies are recognised. The species naturally occurs in the Northern Cape and Western Cape provinces of South Africa.

<i>Felicia</i> (plant) Genus of shrublets, perennials and annuals in the daisy family

Felicia is a genus of small shrubs, perennial or annual herbaceous plants, with 85 known species, that is assigned to the daisy family. Like in almost all Asteraceae, the individual flowers are 5-merous, small and clustered in typical heads, and which are surrounded by an involucre of, in this case between two and four whorls of, bracts. In Felicia, the centre of the head is taken by yellow, seldom whitish or blackish blue disc florets, and is almost always surrounded by one single whorl of mostly purple, sometimes blue, pink, white or yellow ligulate florets and rarely ligulate florets are absent. These florets sit on a common base and are not individually subtended by a bract. Most species occur in the Cape Floristic Region, which is most probably the area where the genus originates and had most of its development. Some species can be found in the eastern half of Africa up to Sudan and the south-western Arabian peninsula, while on the west coast species can be found from the Cape to Angola and one species having outposts on the Cameroon-Nigeria border and central Nigeria. Some species of Felicia are cultivated as ornamentals and several hybrids have been developed for that purpose.

<i>Gazania pectinata</i> Species of plant

Gazania pectinata, the cockscomb Gazania, is a species of calendula native to the lower-lying regions and coastal plains of the Western Cape Province, South Africa.

<i>Gazania rigida</i> Species of plant

Gazania rigida, the "Karoo Gazania", is a species of flower native to the Western Cape and Northern Cape Provinces of South Africa.

<i>Gazania serrata</i> Species of plant

Gazania serrata is a species of flowering plant in the family Asteraceae, native to the Northern Cape and Western Cape provinces, South Africa.

Gazania maritima is one of the flowers known as a calendula, native to the Western Cape province, South Africa.

References

  1. "Gorteria L." Plants of the World Online. Royal Botanic Gardens, Kew. 2023. Retrieved 25 March 2023.
  2. 1 2 3 4 5 6 7 Stångberg, Frida; Anderberg, Arne A. (2014). "Morphology and taxonomic reclassification of Gorteria (Asteraceae)". Willdenowia . 44 (1): 97–120. JSTOR   24750917.
  3. "Gorteria personata L." The Plantlist. Retrieved 2018-01-29.