Rapateaceae

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Rapateaceae
Stegolepis guianensis on the Roraima tepui in Venezuela

Stegolepis guianensis on the Roraima tepui in Venezuela

Systematics
Subdivision : Seed plants (Spermatophytina)
Class : Bedecktsamer (Magnoliopsida)
Monocots
Commelinids
Order : Sweet grass (Poales)
Family : Rapateaceae
Scientific name
Rapateaceae
Dumort.

The Rapateaceae are a family of plants belonging to the order of the sweet grass-like (Poales). It contains 16 to 17 genera with around 80 to 94 species . With the exception of Maschalocephalus dinklagei , all species are neotropically distributed.

description

Illustration from The flora of Africa, especially its tropical regions - Basic features of the plant distribution in Africa and the character plants of Africa , 1910 by Maschalocephalus dinklagei

Habit and leaves

The species of the Rapateaceae are mostly tough, perennial herbaceous plants with rhizomes . They rarely grow epiphytically, mostly terrestrially, often in nutrient-poor soils .

The leaves are alternate, usually arranged in three rows or in a spiral and rosette at the base of the plant. The leaves are divided into leaf sheath, petiole (for example Saxofridericia ) and leaf blade, or a petiole is missing. The leaf sheath is open. The simple leaf blade is flat or folded (usually V-shaped) or pencil-shaped, with parallel veins and entire margins. The leaf blade is often turned 90 ° and can be clearly asymmetrical, in which case the median nerve is clearly shifted to one side. The stomata are paracytic.

Inflorescences and flowers

Laterally very long, leafless inflorescence shafts are usually formed; in Maschalocephalus they are greatly reduced. In heady to one-sided, racemose total inflorescences, there is rarely a partial inflorescence, but mostly many annual or panicley partial inflorescences with many flowers. The partial inflorescences rarely have only one, usually two bracts , which can sometimes be fused; they are usually large and broad at their base and rarely completely envelop the partial inflorescences. The partial inflorescences act more or less as pseudanthium with a kind of spathe . There are one or more bracts under each flower.

The hermaphrodite flowers are radially symmetrical to somewhat zygomorphic and threefold with double perianth . The three sepals are sometimes fused at the base. The three delicate petals are mostly fused at their base and are not long-lasting; they are mostly yellow or sometimes red and sometimes have brown to purple markings. The flowers contain two circles with three fertile stamens each . The stamens are free or fused with each other at the base and fused with the petals in some species. The anthers open with pores. Three carpels have become a top permanent ovary grown. There are one to two or five to fifty anatropic ovules in each of the three ovary chambers . In Spathanthus only one of the three ovary chambers is fertile. The stylus ends in a simple, head-shaped scar. Pollination occurs by insects ( entomophilia ) or birds ( ornithophilia ).

Fruits and seeds

Loculicidal capsule fruits are formed. The winged or wingless seeds contain a small embryo ( rudimentary when the seeds are mature ) and a well-developed endosperm with some starch .

Ingredients and chromosome number

In the epidermis there are several more or less glandular pebbles and brown cells containing tannins. All species accumulate aluminum mostly in large amounts, only a few species in low doses; otherwise this seldom occurs in monocotyledons. There are mucous cells.

The number of chromosomes in Maschalocephalus , for example, is 2n = 22.

Stegolepis guianensis

Systematics and distribution

With one exception, the Rapateaceae only occur in the Neotropics . They thrive in tropical to subtropical climates. Most of the species are native to tropical eastern South America, with some species reaching as far as Bolivia and Panama. The center of biodiversity is the Guiana Shield from the lowlands to the Tepuis . Only the African genus Maschalocephalus with the species Maschalocephalus dinklagei in tropical West Africa in Sierra Leone and Liberia is paleotropic ; it got there by long-distance propagation. The origin of the family is dated 112 million years ago with adaptive radiation about 65 million years ago.

The surname Rapateaceae was published in 1829 by Barthélemy Charles Joseph Dumortier in Analyze des Familles de Plantes , 60, 62. The type genus is Rapatea Aubl.

There are 16 to 17 genera , seven of which are monotypical , with a total of about 80 to 94 species in this family. It is divided into three subfamilies:

  • Rapateoideae Maguire : It contains three genera with about 29 species:
    • Cephalostemon R.H. Schomb. : It contains about five types.
    • Rapatea Aubl. : It has the widest distribution of all genera within the family from northern South America to Peru and contains about 21 species.
    • Spathanthus Desv. : It contains only two types.
  • Monotremoideae Givnish & PEBerry : It contains four genera and eight species.
  • Saxofridericioideae Maguire : The leaves are always stalked. It contains nine to ten genera with around 54 species:
    • Amphiphyllum Gleason : It contains only one species:
    • Duckea Maguire : The four or so species are common in Venezuela and Brazil.
    • Epidryos Maguire (Syn .: Epiphyton Maguire ): The three or so species are distributed from Panama to Colombia.
    • Guacamaya Maguire : It contains only one type:
    • Kunhardtia Maguire : The only two types occur in Venezuela.
    • Marahuacaea Maguire : it contains only one species:
    • Phelpsiella Maguire : It contains only one species:
    • Saxofridericia R.H. Schomb. or other spelling Saxo-Fridericia R.H. Schomb. : The nine or so species occur on the Guiana Shield from the lowlands up to the Tepuis.
    • Schoenocephalium Seub. : The four to seven species are common in Colombia, Venezuela and Brazil.
    • Stegolepis Klotzsch ex grain. : The more than 30 species are distributed in northern South America, especially in the highlands of Guyana and Panama.

swell

  • The family of rapateaceae in APWebsite . (Sections Description and Systematics)
  • The Rapateaceae family at DELTA: L. Watson and MJDallwitz. (Section description)
  • Thomas J. Givnish, Kendra C. Millam, Timothy M. Evans, Jocelyn C. Hall, J. Chris Pires, Paul E. Berry, Kenneth J. Sytsma: Ancient Vicariance or Recent Long-Distance Dispersal? Inferences about Phylogeny and South American-African Disjunctions in Rapateaceae and Bromeliaceae Based on ndhF Sequence Data In: International Journal of Plant Sciences , Volume 165, 2004, Supplement, pp. 35-54: PDF. (Section systematics; PDF; 1.4 MB)
  • Darren M. Crayn, J. Andrew C. Smith, Klaus Winter: Carbon-Isotope Ratios and Photosynthetic Pathways in the Neotropical Family Rapateaceae. In: Plant Biology , Volume 3, No. 5, 2001, pp. 569-576: PDF. (PDF; 191 kB)

Individual evidence

  1. ↑ Robert Hegnauer : Monocotyledoneae . In: Chemotaxonomy of Plants . tape  2 . Birkhäuser, Basel 1963, ISBN 978-3-7643-0165-1 , p. 425-427 ( Rapateaceae on pp. 425-427 in Google book search).
  2. ↑ Thomas J. Givnish, Kendra C. Millam, Timothy M. Evans, Jocelyn C. Hall, J. Chris Pires, Paul E. Berry, Kenneth J. Sytsma: Ancient Vicariance or Recent Long-Distance Dispersal? Inferences about Phylogeny and South American-African Disjunctions in Rapateaceae and Bromeliaceae Based on ndhF Sequence Data. In: International Journal of Plant Sciences , Volume 165, 2004, Supplement, pp. 35-54: Online. ( Memento of the original from August 9, 2017 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF; 1.4 MB) @1@ 2Template: Webachiv / IABot / www.botany.wisc.edu
  3. ↑ Rapateaceae in the Germplasm Resources Information Network (GRIN), USDA , ARS , National Genetic Resources Program. National Germplasm Resources Laboratory, Beltsville, Maryland.
  4. ↑ The family of rapateaceae in APWebsite .
  5. ↑ Rafaël Govaerts, 1999: World Checklist of Seed Plants 3 (1, 2a & 2b) , 1-1532. MIM, Deurne. Rafaël Govaerts (Ed.): Rapateaceae. In: World Checklist of Selected Plant Families (WCSP) - The Board of Trustees of the Royal Botanic Gardens, Kew . Retrieved December 6, 2014.

Web links

Commons : Rapateaceae  - collection of images, videos and audio files