Grabowskia
Grabowskia obtusa in the Argentine National Park Talampaya
Grabowskia is a genus of flowering plants of the nightshade family (Solanaceae ). The four species belonging to the genus are widespread in America. The Gattungsepitheton honors the German botanist Heinrich Emanuel Grabowski.
- 3.1 Internal systematics
- 3.2 External systematics
- 4.1 Literature
- 4.2 Notes and references
Description
Vegetative characteristics
Grabowskia species are usually 1.5 to 2.5 m tall shrubs, sometimes they are only up to 0.5 m high. Rarely there are small trees with a height of up to 5 m and a stem base diameter of up to 40 cm. They grow upright and branched, the stems are armed with spines. Young branches are smooth and slightly shiny, dark mahogany -colored to blackish. At the age they are cracked.
The leaf blades are thick, their shape ranges from obovate or inverted ovoid over elliptic to broadly elliptic. At the top they can be rounded or blunt, the base is tapered and the petiole decurrent. The leaves are glabrous or glandular trichomes with hairy with a short stalk and a multicellular head and later glabrous. They may be colored blue or greenish- blue and are usually 15 to 28 ( often 8 to 40 ) mm long and 20 to 25 ( often 14 to 35 ) mm wide. Exception is Grabowskia megalosperma with very narrow leaves.
Inflorescences and flowers
The flowers can be scented or scentless. They are available individually or in groups of two to twelve zymösen piece. The flower stalks are 5-8 mm long, making it about as long as the calyx. This is cup-shaped, radial symmetry, five-lobed or five divided and always shorter than the corolla tube. The crown is slightly zygomorphic, 8-12 (rarely to 15) mm long. It is white - yellowish or greenish, or colored white and purple or violet. The venation is usually green, brown or dark colored purple. The corolla tube is conical or nearly cylindrical and 1.5 to 2.5 times longer than the calyx lobes. These are wider than long, auriculate, bent back or provided with bent edge.
Stamens and pistils are on the bloom out. The stamens are the same varied and set at approximately the lower third of the corolla tube or slightly above or below. The stamens are longer than the anthers and hairy on the lower half. The back ( dorsal) attached dust bags are 2.1 to 3.1 (rarely 1.9 to 3.5 ) mm long, the counters are nearly free from each other on the entire lower half. The pollen grains are trizonokolporat and medium in size with a size of about 25.3 microns. The ovary is zweifächerig, each carpel is zweikammerig single chamber at the base and in the upper 2/3 by a transverse standing partition. Each of said chambers thus formed includes two ovules, wherein the upper is greater than the lower ones. The scar is disc-shaped, depressed and is on a slightly reversed friemförmigen stylus.
Fruit and seeds
The fruits are obovate or nearly spherical, yellow, orange - yellow or bluish-colored black. They are partially surrounded by not enlarging calyx. They contain two elongated nuclei with a rounded tip and a dreigezähnten basis. Each core includes a single upright seeds occasionally two seeds are formed, the upper one is significantly larger than the bottom.
Dissemination
The species occur in a disjunct area in America, where Grabowskia boerhavieafolia has the largest distribution: The species occurs in Mexico, the Galapagos Islands, Peru, Chile, Bolivia and western Argentina ago. The other species occur in Argentina and neighboring countries.
System
Inside systematics
Within the genus four types can be distinguished:
- Grabowskia boerhaviifolia ( L. F. ) Schltdl.
- Grabowskia duplicatà Arnott.
- Grabowskia megalosperma Speg.
- Grabowskia obtusa Arnott.
Type species is Grabowskia boerhaviaefolia.
Outer systematics
The genus Grabowskia is within the scheme of the nightshade family along with the genera Bock mandrels ( Lycium ) and Phrodus classified in the tribe Lycieae. Phylogenetic analyzes of the tribe showed that the tribe is monophyletic, the two genera Phrodus and Grabowskia, however, are placed inside the goat spines. Phrodus forms a Schwesterklade to almost all species of the genus Lycium. The exception of some species, which are characterized by stone body in fruits, mostly white, drooping, relatively large flowers with calyx lobes longer than the calyx tube and flat, often blue -green leaves. The genus Grabowskia is a Schwesterklade to this latter group of Lycium species.