Phenakospermum guyannense
| Phenakospermum guyannense | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Habit of a young plant with long petioles and simple leaf blades |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name of the genus | ||||||||||||
| Phenacospermum | ||||||||||||
| Final | ||||||||||||
| Scientific name of the species | ||||||||||||
| Phenakospermum guyannense | ||||||||||||
| ( A.Rich. ) Endl. ex Miq. |
The Phenakospermum guyannense is the only plant species of the monotypic genus Phenakospermum in the Strelitziae family . It is native to the Neotropic .
description
Appearance and leaves
Phenakospermum guyannense grows as a large, perennial herbaceous plant and reaches heights of over 10 meters. It forms stocks through sympodial rhizomes . All parts of the plant are hairless. A “pseudo trunk” is formed with heights of 3 to 7.4 meters and a diameter of 11 to 17 centimeters, the overlapping leaf sheaths are preserved around an unbranched, fibrous trunk; as an exception within the Zingiberales order, it lignifies something.
The alternate and more or less two-line arranged leaves are up to 3 meters long and are divided into leaf sheath, petiole and leaf blade. The petiole has a length of 0.37 to 1.92 centimeters and a diameter of 2.0 to 3.2 centimeters. The large, simple leaf blade is glabrous, 1.0 to 2.7 meters long and 47 to 85 centimeters wide. There is a thick main nerve (midrib) and side nerves parallel to each other, all of which unite on the smooth leaf margin.
Inflorescences and flowers
The flowering period extends from the end of the rainy season to the middle of the dry season. There is an upright, 1.2 to 2.0 meter long inflorescence stem, which has a diameter of 7 to 18 cm. The terminal, upright inflorescence is composed of several partial inflorescences and can produce flowers for two to four months. At a rachis with a diameter of 2.5 to 9 cm in two rows at an angle of 90 ° from three to ten boat-shaped supporting sheets arranged the up wide greenish yellow with a layer of wax, 23 cm cm long and in her 18-to 34 to 44 ; Above each is a partial inflorescence with up to 25 flowers. A 1 to 1.2 cm long flower stalk stands over a cream-colored, 17 to 34 cm long and at its base 5.8 to 8.5 cm wide bract .
The approximately 28 cm long, hermaphrodite flowers are zygomorphic and threefold. There are two clearly different circles, each with three bracts , which have grown together to form a white tube with a length of 9 cm and a diameter of 1.8 cm. Of the free areas of the three 3.5 cm wide, cream-white sepals, one is 17 cm and the other 18 cm. Two of the three petals are not fused at their base, but only from half their length to their end and are 14 cm long and 2.5 cm wide, the free third petal is 12 cm long and 3 cm wide; they are creamy white with a dark green, bent back edge. There are five fertile stamens and one staminodium is missing. The ruler stamens are relatively long with about 8.5 cm. The anthers are linear with a length of about 7 cm. The three carpels are one under constant, dreikammerigen white ovary adherent having a length of about 3.5 cm and a diameter of about 2 cm has. In each ovary chamber there are many ovules in four rows.
There are deeply sunken septal nectaries . Each flower produces 1.2 to 3 ml of hexose-dominated (on average around 17% hexose ) nectar, which, however, is not reproduced again. The flowers open just before sunset and can only be pollinated for one night. The pollination is effected by bats ( Chiropterophilie ).
Fruits and seeds
A green, woody, triple, loculicidal capsule fruit with a length of about 15 cm and a diameter of about 8 cm is formed, which contains many (up to 400) seeds. With a length of 8 to 10 mm and a diameter of 6 to 8 mm, the shiny black seeds have a starchy endosperm and a red to orange-colored, fibrous aril . The brightly colored aril attracts birds to spread.
Chromosome number
The number of chromosomes is 2n = 22.
distribution
The neotropical Phenakospermum guyannense is originally found in South America only east of the Andes in the Amazon basin and sometimes thrives in forests along the seasonally flooded savannas . The distribution area extends from Colombia, Ecuador, Guiana, Suriname, French Guiana, Venezuela, Bolivia and Peru to Brazil.
Systematics
The first description of this species took place in 1831 under the name Urania guyannensis by Achille Richard in Nova Acta Physico-medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta , 15 (Supl.), 21, plates 6-7. The genus Phenakospermum was established in 1833 by Stephan Ladislaus Endlicher in Prodromus Florae Norfolkicae , 35, p. 98. This species was given the valid name Phenakospermum guyannense in 1845 by Stephan Ladislaus Endlicher in Friedrich Anton Wilhelm Miquel Botanische Zeitung (Berlin) , 3, 345, there in the wrong spelling (n instead of nn) Phenakospermum guyanense . More synonyms for Phenakospermum guyannense (Rich.) Endl. ex Miq. are: Ravenala guyannensis (Rich.) Steud. , Urania amazonica Mart. , Phenakospermum amazonicum (Mart.) Miq. , Musidendron amazonicum (Mart.) Nakai .
use
Little is known about its use by humans. The seeds are cooked and eaten by some indigenous peoples .
swell
- WJ Kress, DE Stone: Morphology and floral biology of Phenakospermum (Strelitziaceae), an arborescent herb of the Neotropics. In: Biotropica. 25, 1993, pp. 290-300.
- Phenacospermum at Zingiberaceae of the National Museum of Natural History (NMNH) of the Smithsonian Institution .
Individual evidence
- ↑ Phenakospermum_guyannense at Tropicos.org. In: IPCN Chromosome Reports . Missouri Botanical Garden, St. Louis
- ↑ Rafaël Govaerts (ed.): Phenakospermum. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved June 5, 2020.
- ↑ Phenakospermum_guyannense at Tropicos.org. Missouri Botanical Garden, St. Louis, accessed January 5, 2017.
