Tovaria

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Tovaria
Tovaria pendula

Tovaria pendula

Systematics
Nuclear eudicotyledons
Rosids
Eurosiden II
Order : Cruciferous (Brassicales)
Family : Tovariaceae
Genre : Tovaria
Scientific name of the  family
Tovariaceae
Pax
Scientific name of the  genus
Tovaria
Ruiz & Pav.

The tovaria are the only genus of the monogeneric family Tovariaceae from the order of the cruciferous (Brassicales). The only two species are native to the Neotropics .

description

Illustration of Tovaria pendula .

Appearance and leaves

Tovaria species grow as annual to perennial herbaceous plants , semi-shrubs or smaller shrubs . When wood is formed, the annual rings are completely missing . The line vessels are only simply spotted . The root has a thin layer of endodermis .

The alternate leaves are arranged in a petiole and a leaf blade. A typical feature are the rough, three-part leaf blades with a smooth leaf margin. The stomata are anomocytic (without secondary cells) and correspond to the so-called Ranunculaceae type . The leaf vein is simply arched. The stipules are located directly on the stem or on the leaf base or they are usually absent.

Inflorescences and flowers

Tovaria species form terminal, loosely structured and axillary, racemose inflorescences with bracts .

The hermaphroditic flowers are radially symmetrical and usually eight-fold, more rarely six or nine-fold with a double flower envelope . Within the flower, there is nectar production , which is delivered via modified stomata. All flower components are clearly developed. The sepals are not fused. The petals can be nailed briefly, their color varies between yellow, green and whitish. There are also eight, more rarely six or nine fertile stamens , whereby they face the sepals according to the rule of alternation , so the inner circle of the stamen is missing; they are not fused with each other or with the petals. A gynophore is present, but relatively short. The six-part scar , sitting on a short stylus , is capable of nastic movements and can spread. Six, rarely five or eight carpels have become a top permanent ovary grown. In Tovaria diffusa , the carpels are in alternation to the stamens. In tovaria pendula this could not be observed; but here a variation of the individual flower organs within an inflorescence was observed. There are many rows of ovules per carpel, which are first anatropic . After fertilization, these will be the further development of Exotegmen but campylotrop . Further features observed in the ovules are a curved micropyle and an elongated funiculus .

Fruits and seeds

The fruit is a berry and contains a large number of small seeds. The cells outside the ovule may be enlarged, but inside the testa they are small.

Chromosome number

The basic chromosome number is n = 14.

Systematics and distribution

The genus Tovaria was first published in 1794 by the Spanish botanists Hipólito Ruiz López and José Antonio Pavón y Jiménez (Ruiz & Pav.) In Flora Peruvianae, et Chilensis Prodromus , 49.Type species is Tovaria pendula Ruiz et Pavon ( Systema Vegetabilium Florae Peruvianae et Chilensis , 1798, p. 85.). Synonyms for Tovaria Ruiz & Pav. Are Bancroftia Macfad. and Cavaria Steud. The Tovariaceae family was established in 1891 by Ferdinand Albin Pax in Engler and Prantl: The Natural Plant Families , 3, 2nd edition, 1936, p. 207.

Tovaria is the only genus in the Tovariaceae family. As a result of reclassifications based on recent molecular biological investigations, which do not seem to be final, only two species of the genus Tovaria currently remain in this genus.

The distribution area of the two Tovaria species is the Neotropic . The two species are distributed from Mexico across Central America and in the Caribbean only Jamaica to northern and northwestern South America .

There are only two tovaria typologies:

The homonym Tovaria Neck. ex Baker is a synonym for the genus Maianthemum and not to be confused with the genus mentioned above.

Phytochemistry

The species of the Tovariaceae family belong to those plants that typically have mustard oil glycosides (also glucosinolates) and the corresponding glucosinolate cleavage enzyme , myrosinase . This indicates the close relationship to the caper family (the genus Tovaria was previously classified there) and to the Brassicaceae. The production of tannin is also detectable.

swell

Much of the information in this article has been obtained from the following sources:

Individual evidence

  1. (de Lagerheim 1892)
  2. FD Boese angle: ovule and seed development of tovaria pendula Ruiz et Pavon. In: Botanical yearbooks for systematics, plant history and plant geography. Leipzig , Volume 111, 1990, pp. 389-401.
  3. ^ Tovariaceae at Tropicos.org. Missouri Botanical Garden, St. Louis
  4. ^ Tovaria at Tropicos.org. Missouri Botanical Garden, St. Louis, Retrieved July 8, 2017.
  5. ( Appel and Bayer 2002 )

Further reading:

  • Peter Goldblatt : Chromosome number in two cytologically unknown New World families, Tovariaceae and Vivianiaceae. In: Annals of the Missouri Botanical Garden , Volume 65, Issue 2, 1978, pp. 776-777.

Web links

Commons : Tovaria  - collection of images, videos and audio files
  • PJM Maas, H. Maas-van de Kamer, 2012: Neotropical Tovariaceae. In: W. Milliken, Bente Bang Klitgaard, A. Baracat: Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. (2009 onwards)