Theaceae

Blossom of a tea plant (Camellia sinensis)

The Teestrauchgewächse ( Theaceae ) are a family of plants in the order of the heather -like ( Ericales ). Economically important species are the tea plant (Camellia sinensis), Camellia oleifera as a cooking oil supplier and the camellia varieties (Camellia japonica) as an ornamental plant. Especially of the genus Camellia ingredients were tested for their medicinal effects.

• 4.1 Notes and references

Description

Vegetative characteristics

These are woody plants: mostly evergreen small ( maximum plant height of 20 meters) trees or shrubs. There are unicellular trichomes present or they are hairless. The alternate and spirally arranged or distichous on the branches, stalked or sessile leaves have always shiny, leathery and simple leaf blade, which is often asymmetrical. The leaf margin is often cut. The leaves turn red before they fall often. Stipules absent.

Generative features

The flowers are usually solitary in the leaf axils on two or up to seven bracts or in few-flowered inflorescences. The usually hermaphroditic, unisexual in Laplacea, flowers are often very striking and radial symmetry. The usually five, rarely six or more rarely, sepals and five to six, rarely up to ten petals can free up sometimes grown slightly at its base and (usually) be arranged spirally both whorled like. Often sepals and petals go gradually into one another. There are numerous (more than 40), only fertile, centrifugally arranged stamens present. The most long stamens are usually grown free or rarely at their base to completely and the anthers are short. Most five (three to ten) carpels are fused into a superior ovaries. The carpel are two to a few ovules available. There are three to five free to just measuring stylus available with intergrown capitate scars or fused completely to a stylus, which ends in stigma lobes. In the female flowers of Laplacea staminodes are present.

There are spherical, woody, lokulizidal, about 2 cm long seed capsules formed on which the sepals are still present and contain several seeds. Seeds are often flat over 4 to 20 mm long and have a straight embryo. The seeds are winged Laplacea.

Ingredients

In many tissues, the so-called Teestrauchgewächse sclereids are present, ie, Cells of different shape with strongly thickened cell walls; they are often recognizable as tiny dots, for example, on the leaf blades. Accumulate aluminum ions. They contain ellagic acid and myricetin.

Dissemination

Many fossils from the Late Cretaceous and Tertiary of the total allocated to the Theaceae. Previously had this family as important components of forests widespread in the moderate latitudes in the northern hemisphere.

The Teestrauchgewächse occur in the tropics and subtropics. The family now has a disjoint area. Centers of distribution are now the east to southeast Asia and Malaysia's. The east and southeast of North America is home to about four species.

A good portion of the species grows as undergrowth in mountain forests.

System

The family Theaceae in 1816 by Charles François de Brisseau Mirbel in Botanical Register; Consisting of colored. . . , Table 112 published. Type genus is Thea L., now a synonym of Camellia L. Synonyms for Theaceae Ker Gawl. are: Camelliaceae DC, Gordoniaceae Sprengel and Malachodendraceae J.Agardh. .

The Theaceae sl family, which earlier consisted of approximately 30 to 40 genera with more than 600 species, Sladeniaceae, Pentaphylacaceae (including Ternstroemiaceae ) and Tetrameristaceae (including Pellicieraceae ) is today s.str in the families Theaceae. , Divided (see APG III ).

Today the Theaceae contain only the taxa that were formerly classified in the subfamily of Theo ideae. The Theaceae family s.str. contains three tribes organized today in about seven to twelve genera with about 195-460 species. The division into genera and species is difficult and varies significantly depending on the author, as among themselves, the relationships and boundaries of individual species needs further molecular biological studies.

Tribus with genera:

• Tribus Theeae Szyszylowicz: it contains five genera: Apterosperma Hung T.Chang: it contains only one type: Apterosperma oblata Hung T.Chang: This endangered tree species are found in forests at altitudes 800-1300 m only in the southern Chinese provinces of Guangdong and Guangxi.

• Tribus Gordonieae DC:. Contains three genera: Franklinia W.Bartram ex Marshall: It contains only one type: Franklinia alatamaha Marshall: The home is only Georgia.

• Tribus Stuartieae Choisy: it contains only one genus: Stewartia L.: (including Hartia Dunn) The approximately 20 species are distributed in China ( 15 species ), Japan, Korea, Laos, Vietnam and eastern North America (2 species).

Swell

• The Theaceae on the APWebsite family. (Section Description and systematics)
• Tianlu Min & Bruce Bartholomew: Theaceae in the Flora of China, Volume 12, p 366: description and identification key of Chinese taxa. (Section Description and systematics)
• Linda M. Prince: Theaceae in the Flora of North America, Volume 8, page 322: description and identification key of North American taxa. (Section Description and systematics)
• Linda M. Prince: A brief nomenclatural review of genera and Tribes in Theaceae Aliso 24, 2007, pp. 105-121. PDF online.
• Jon LR Every: Neotropical Theaceae in Neotropikey of the Royal Botanic Gardens, Kew. ( Description section )