Araucaria

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Araucaria
Temporal range: Jurassic - recent
Araucaria columnaris
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Araucariaceae
Genus: Araucaria
Juss.

Araucaria is a genus of evergreen coniferous trees in the family Araucariaceae. There are 19 species in the genus, with a scattered distribution. They are found in New Caledonia (where 13 species are endemic), Norfolk Island, eastern Australia, New Guinea, Argentina, Chile, and southern Brazil.

The present populations are relicts, and of restricted distribution. They are found in forest and shrubland, in exposed sites. These tall trees are living fossils, dating back to early in the Mesozoic era.

Fossil records show that the genus also formerly occurred in the northern hemisphere until the end of the Cretaceous period. By far the greatest diversity exists in New Caledonia, due to the island's long isolation and stability.

Description[change | edit source]

Araucaria are mainly large trees with a massive erect stem, reaching a height of 30–80 m. The horizontal, spreading branches grow in whorls and are covered with leathery or needle-like leaves. In some species, the leaves are narrow awl-shaped and lanceolate, barely overlapping each other, in others they are broad and flat, and overlap broadly.