Tetrachondraceae
Polypremum procumbens
The Tetrachondraceae are a plant family in the order of Lippenblütlerartigen ( Lamiales ).
Description
Tetrachondraceae are small, crawling to upright -growing, perennial herbaceous plants. Two types are containing essential oils succulents. One type is a water plant. The opposite leaves are constant small, simple, leathery and usually stalked only briefly. The leaf edges are serrated tiny.
The flowers are individually either terminally or in the leaf axils. The radial symmetry, hermaphroditic, very small flowers are cruciform with a double perianth. The four sepals are fused bell-shaped. The four white petals are fused Roehrig or bell-shaped. You only have a circle with four fertile stamens, which are mutually free. Two carpels are a top permanent or semi- inferior ovary fused with a stylus with a small scar. The ovary is divided secondarily by a false septum, arise four chambers.
It is formed by either a two-chamber capsule fruit or a fruit of four nutlets.
Systematics and distribution
Tetrachondra was arranged in the Boraginaceae or in the Lamiaceae. Polypremum was always placed close to the Loganiaceae. The Tetrachondraceae family was erected in 1924 by Richard Wettstein.
The family has a disjoint area: firstly, New Zealand and Australia; on the other Patagonia and the southern United States to South America.
To the family of Tetrachondraceae include only two genera and about three ways:
- Polypremum L.: It contains only one type: Polypremum procumbens L.: Their home ranges from the southern United States to South America.
- Tetrachondra hamiltonii Petrie ex Oliv. Home is New Zealand.
- Tetrachondra patagonica Skottsb. The home is Patagonia.
Swell
- The Tetrachondraceae family in APWebsite (sections systematics and description)
- The Tetrachondraceae family at DELTA. ( Description section )
- Entry in New South Wales Flora Online. ( Description section )
- Tetrachondraceae in the Germplasm Resources Information Network ( GRIN), USDA, ARS, National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland. Accessed on 13 March 2014.