Araucaria (; original pronunciation: a.ɾawˈka.) is a genus of evergreen trees in the family Araucariaceae. While today they are largely confined to the Southern Hemisphere, during the Jurassic and Cretaceous they were globally distributed. There are 20 extant taxon species in New Caledonia (where 14 species are endemism, see New Caledonian Araucaria), eastern Australia (including Norfolk Island), New Guinea, Argentina, Brazil, Chile and Uruguay.
The genus is familiar to many people as the genus of the distinctive Chilean pine or monkey-puzzle tree ( Araucaria araucana). No distinct vernacular name exists for the genus. Many are called "pine", although they are only distantly related to true pines, in the genus Pinus.
Description
Araucaria are mainly large trees with a massive erect stem, reaching a height of . The horizontal, spreading branches grow in whorls and are covered with leathery or needle-like
leaf. 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.
The trees are mostly dioecious, with male and female Conifer cone found on separate trees, though occasional individuals are Plant sexuality or change sex with time. The female cones, usually high on the top of the tree, are globose, and vary in size among species from in diameter. They contain 80–200 large Eating seeds, similar to , though larger. The male cones are smaller, long, narrow to broad cylindrical, and broad.
Taxonomy
The genus is named after the Spanish
exonym Araucano ("from
Arauco Province") applied to the
Mapuche of south-central
Chile and south-west
Argentina, whose territory incorporates natural stands of a species in this genus identified as
A. araucana; the Mapuche people call it
pewen, and consider it sacred.
Some Mapuche living in the Andes name themselves
Pehuenche ("people of the
pewen") as they traditionally harvested the seeds extensively for food.
There are four extant sections and two extinct sections in the genus, sometimes treated as separate genera.
Extant species
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| | Araucaria araucana – monkey-puzzle or pehuén | central Chile & western Argentina. |
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| | Araucaria bernieri | New Caledonia |
| | Araucaria biramulata | New Caledonia |
| | Araucaria columnaris - Cook pine | New Caledonia |
| | Araucaria cunninghamii - Moreton Bay pine, hoop pine | Eastern Australia, New Guinea |
| | Araucaria goroensis | New Caledonia |
| | Araucaria heterophylla – Norfolk Island pine | Norfolk Island |
| | Araucaria humboldtensis | New Caledonia |
| | Araucaria laubenfelsii | New Caledonia |
| | Araucaria luxurians | New Caledonia |
| | Araucaria montana | New Caledonia |
| | Araucaria muelleri | New Caledonia |
| | Araucaria nemorosa | New Caledonia |
| | Araucaria rulei | New Caledonia |
| | Araucaria schmidii | New Caledonia |
| | Araucaria scopulorum | New Caledonia |
| | Araucaria subulata | New Caledonia |
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Genetic studies
Genetic studies indicate that the extant members of the genus can be subdivided into two large
– the first consisting of the sections
Araucaria,
Bunya, and
Intermedia; and the second of the strongly
monophyletic section
Eutacta. Sections
Eutacta and
Bunya are both the oldest taxa of the genus, with
Eutacta possibly older.
- :Taxa marked with are extinct.
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Section Araucaria. Leaves broad; cones more than diameter; seed germination hypogeal. Syn. sect. Columbea; sometimes includes Intermedia and Bunya
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Araucaria angustifolia – Paraná pine (obsolete: Brazilian pine, candelabra tree); southern and southeastern Brazil, northeastern Argentina.
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Araucaria araucana – monkey-puzzle or pehuén (obsolete: Chile pine); central Chile & western Argentina.
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Araucaria nipponensis – Japan and Sakhalin (Upper Cretaceous)
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Section Bunya. Contains only one living species. Produces recalcitrant seeds with hypogeal (cryptocotylar) germination,
though extinct species may have exhibited epigeal germination.
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Araucaria bidwillii – bunya-bunya; Eastern Australia
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Section Intermedia. Contains only one living species. Produces recalcitrant seeds
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Araucaria hunsteinii – klinki; New Guinea
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Araucaria haastii - New Zealand (Cretaceous)
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Section Eutacta. Leaves narrow, awl-like; cones less than diameter; seed germination epigeal
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Araucaria bernieri – New Caledonia
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Araucaria biramulata – New Caledonia
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Araucaria columnaris – Cook pine; New Caledonia
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Araucaria cunninghamii – Moreton Bay pine, hoop pine; Eastern Australia, New Guinea
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Araucaria goroensis – New Caledonia
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Araucaria heterophylla – Norfolk Island pine; Norfolk Island
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Araucaria humboldtensis – New Caledonia
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Araucaria laubenfelsii – New Caledonia
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Araucaria luxurians – New Caledonia
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Araucaria montana – New Caledonia
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Araucaria muelleri – New Caledonia
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Araucaria nemorosa – New Caledonia
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Araucaria rulei – New Caledonia
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Araucaria schmidii – New Caledonia
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Araucaria scopulorum – New Caledonia
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Araucaria subulata – New Caledonia
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Araucaria lignitici – (Paleogene) Yallourn, Victoria, Australia
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Araucaria famii – (Late Cretaceous) Vancouver Island, Canada.
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Section Yezonia. Extinct. Contains only one species
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Araucaria vulgaris – Japan (Late Cretaceous)
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Section Perpendicula. Extinct. Contains only one species
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Araucaria desmondii - New Zealand (Late Cretaceous)
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incertae sedis
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Araucaria beipiaoensis – Tiaojishan Formation, China (Middle Jurassic)
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Araucaria fibrosa – López de Bertodano Formation, Antarctica (Late Cretaceous)
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Araucaria marensii – La Meseta Formation, Antarctica & Santa Cruz Formation, Argentina
[ Araucaria marensii at Fossilworks.org]
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Araucaria nihongii – Upper Yezo Group, Japan (Late Cretaceous)
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Araucaria taieriensis - New Zealand (Late Cretaceous)
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Araucaria brownii - England (Middle Jurassic)
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Araucaria mirabilis – Patagonia (Middle Jurassic)
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Araucaria sphaerocarpa - England (Middle Jurassic)
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Araucaria jeffreyi - Eastern United States (Late Cretaceous)
Araucaria bindrabunensis (previously classified under section
Bunya) has been transferred to the genus
Araucarites.
Distribution and paleoecology
Members of
Araucaria are found in
Argentina,
Brazil,
New Caledonia,
Norfolk Island,
Australia,
New Guinea,
Chile and Papua (Indonesia).
[ The Pine Trees of Lanai] Many if not all current populations are relicts, and of restricted distribution. They are found in
forest and
maquis shrubland, with an affinity for exposed sites. The earliest records of the genus date to the
Middle Jurassic, represented by
Araucaria mirabilis of Argentina, and
Araucaria sphaerocarpa from England.
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, likely due to a relatively recent adaptive radiation, as all New Caledonian species are more closely related to each other than they are to other Araucaria. Much of New Caledonia is composed of ultramafic rock with , with low levels of nutrients, but high levels of metals such as nickel. Consequently, its endemic Araucaria species are adapted to these conditions, and many species have been severely affected by nickel mining in New Caledonia and are now considered threatened or endangered, due to their habitat lying in prime areas for nickel mining activities.
Some evidence suggests that the long necks of sauropod dinosaurs may have evolved specifically to browse the foliage of tall trees, including those of Araucaria. An analysis of modern Araucaria leaves found that they have a high energy content but are slow fermenting, making their ancestors a likely attractive target.
Uses
Some of the species are relatively common in cultivation because of their distinctive, formal symmetrical growth habit. Several species are economically important for
timber production.
Food
The edible large seeds of
A. araucana,
A. angustifolia and
A. bidwillii — also known as
Araucaria nuts,
and often called, although improperly,
pine nuts — are eaten as food, particularly among the
Mapuche people of Chile and southwest Argentina, the
Kaingang people in
Southern Brazil and among Indigenous Australians.
In South America
Araucaria nuts or seeds are called
piñas or
piñones in Spanish and
pinhões in Portuguese, like pine nuts in Europe.
Pharmacological activity
Pharmacological reports on genus Araucaria are
anti-ulcer,
antiviral drug,
neuro-protective,
anti-depressant and
anti-coagulant.
See also
External links