Araucariaceae

Chilean Araucaria (Araucaria araucana)

The (Araucariaceae ) are a very old family of plants within the conifers ( Coniferopsida ). You have a disjoint area in the Southern Hemisphere.

Description

The Araucariaceae are evergreen trees. The narrow or broad leaves are often parallel-veined. The seedlings have four cotyledons ( cotyledons ), but often two grow together.

They are monoecious ( monoecious ) or dioecious ( dioecious ) getrenntgeschlechtig. The male cones are relatively large, cylindrical, with many sporophylls. The pollen grains are wingless. The pollen of the Araucariaceae consist of up to 40 vegetative cells instead of two as usual (remaining conifers Coniferales ), four (with pine Pinaceae plants ) or ten (for podocarps Podocarpaceae ). The upright, female cones are relatively large, ovoid to almost spherical, contain milky sap and take about two years to mature. The seed scales have only one seed.

Dissemination

In the Jurassic and Cretaceous (Araucariaceae ) were the world, more specifically distributed on the Gondwana continent.

After drifting apart of the continents, the family today has a disjoint area. In the northern hemisphere and Africa all species of the family are extinct. In the southern hemisphere representatives of the family today their natural distribution in New Caledonia, New Zealand, Australia and Malaysia, and South America. New Caledonia has a total of 18 species on a particularly high species density. 13 species are endemic to New Caledonia.

System

The Araucariaceae family was erected in 1865 by Johann Baptist Henkel and Christian Ferdinand Friedrich Hochstetter in Synopsis of Nädelhölzer, 17, p 1. Type genus Araucaria Juss is ..

The family Araucariaceae are only three genera with 41 species:

  • Kauri trees ( Agathis Salisb. ): With about 21 species.
  • Araucaria (Araucaria Juss. ): With about 19 species.
  • Wollemia WGJones, KDHill & JMAllen: With a kind: Wollemia ( Wollemia nobilis WGJones, KDHill & JMAllen ): It grows in Tempe rates rainforest in the Australian state of New South Wales. Of this kind is only about 100 wild specimens are known, so it is a highly endangered species

Use

Some species such as the Chilean Araucaria be used as a park trees worldwide. The Brazilian Araucaria timber, however, has as important. It is for example used in instrument, especially for low-priced basses and guitars. The Araucaria (Araucaria heterophylla ) is one of the most well-known species from this family. It prefers bright and cool locations and is also used as a houseplant.

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