Araucaria in the context of Jurassic

A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of Eucalyptus, palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (adaxial) and lower (abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax, and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll which is essential for photosynthesis as it absorbs light energy from the Sun. A leaf with lighter-colored or white patches or edges is called a variegated leaf.

Leaves vary in shape, size, texture and color, depending on the species The broad, flat leaves with complex venation of flowering plants are known as megaphylls and the species that bear them (the majority) as broad-leaved or megaphyllous plants, which also include acrogymnosperms and ferns. In the lycopods, with different evolutionary origins, the leaves are simple (with only a single vein) and are known as microphylls. Some leaves, such as bulb scales, are not above ground. In many aquatic species, the leaves are submerged in water. Succulent plants often have thick juicy leaves, but some leaves are without major photosynthetic function and may be dead at maturity, as in some cataphylls and spines. Furthermore, several kinds of leaf-like structures found in vascular plants are not totally homologous with them. Examples include flattened plant stems called phylloclades and cladodes, and flattened leaf stems called phyllodes which differ from leaves both in their structure and origin. Some structures of non-vascular plants look and function much like leaves. Examples include the phyllids of mosses and liverworts.

Paraná (Brazilian Portuguese: [paɾɐˈna] ) is one of the 26 states of Brazil, in the south of the country. It is bordered in the north by São Paulo state, in the east by the Atlantic Ocean, in the south by Santa Catarina state and the Argentine province of Misiones, and in the west by Mato Grosso do Sul and Paraguay, with the Paraná River as its western boundary. It is subdivided into 399 municipalities, and its capital is the city of Curitiba. Other major cities are Londrina, Maringá, Ponta Grossa, Cascavel, São José dos Pinhais and Foz do Iguaçu. The state is home to 5.4% of the Brazilian population and generates 6.2% of the Brazilian GDP.

Crossed by the Tropic of Capricorn, Paraná has what is left of the araucaria forest, one of the most important subtropical forests in the world. At the border with Argentina is the National Park of Iguaçu, considered by UNESCO as a World Heritage Site. 40 km (25 mi) from there, at the border with Paraguay, the largest dam in the world was built, the Hidroelétrica de Itaipu (Itaipu Hydroelectric Dam). The crime rate is considered low by Brazilian standards and the state is one of the most developed ones in the nation, ranking 4th in gross domestic product, only behind the states of Rio de Janeiro, São Paulo and Minas Gerais.

Wollemia is a genus of coniferous trees in the family Araucariaceae, endemic to Australia. It represents one of only three living genera in the family, alongside Araucaria and Agathis (being more closely related to the latter). The genus has only a single known species, Wollemia nobilis, commonly known as the Wollemi pine (though it is not a true pine) which was discovered in 1994 in a temperate rainforest wilderness area of the Wollemi National Park in New South Wales. It was growing in a remote series of narrow, steep-sided, sandstone gorges 150 km (93 mi) north-west of Sydney. The genus is named after the National Park.

The Wollemi pine is classified as critically endangered (CR) on the IUCN's Red List, and is legally protected in Australia. After it was discovered that the trees could be successfully cloned, new specimens were planted widely around the world in regions with mild temperate climates.

Araucariaceae is a family of conifers with three living genera, Araucaria, Agathis, and Wollemia. While the family's native distribution is now largely confined to the Southern Hemisphere, except for a few species of Agathis in Malesia, it was formerly widespread in the Northern Hemisphere during the Jurassic and Cretaceous periods.

Araucaria araucana, commonly called the pewen, monkey-puzzle, pehuen or piñonero, is an evergreen tree belonging to the family Araucariaceae and growing to a height of 30–40 m (98–131 ft) and a trunk diameter of 1–1.5 m (3.3–4.9 ft). Native to central and southern Chile and western Argentina, it is the hardiest species in the conifer genus Araucaria.

Because of the prevalence of similar species in ancient prehistory, it is sometimes called a 'living fossil'. It is also the official tree of Chile and of the neighboring Argentine province of Neuquén. The IUCN changed its conservation status to Endangered in 2013, because logging, forest fires, and grazing have caused its population to dwindle.

A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of Eucalyptus, palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (adaxial) and lower (abaxial) surfaces that differ in color, hairiness, the number of stomata (pores that intake and output gases), the amount and structure of epicuticular wax, and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll which is essential for photosynthesis as it absorbs light energy from the Sun. A leaf with lighter-colored or white patches or edges is called a variegated leaf.

Leaves vary in shape, size, texture and color, depending on the species. The broad, flat leaves with complex venation of flowering plants are known as megaphylls and the species that bear them (the majority) as broad-leaved or megaphyllous plants, which also include acrogymnosperms and ferns. In the lycopods, with different evolutionary origins, the leaves are simple (with only a single vein) and are known as microphylls. Some leaves, such as bulb scales, are not above ground. In many aquatic species, the leaves are submerged in water. Succulent plants often have thick juicy leaves, but some leaves are without major photosynthetic function and may be dead at maturity, as in some cataphylls and spines. Furthermore, several kinds of leaf-like structures found in vascular plants are not totally homologous with them. Examples include flattened plant stems called phylloclades and cladodes, and flattened leaf stems called phyllodes which differ from leaves both in their structure and origin. Some structures of non-vascular plants look and function much like leaves. Examples include the phyllids of mosses and liverworts.

Fossil wood, also known as fossilized tree, is wood that is preserved in the fossil record. Over time the wood will usually be the part of a plant that is best preserved (and most easily found). Fossil wood may or may not be petrified, in which case it is known as petrified wood or petrified tree. The study of fossil wood is sometimes called palaeoxylology, and a palaeoxylologist is somebody who studies fossil wood.

The fossil wood may be the only part of the plant that has been preserved, with the rest of the plant completely unknown: therefore such wood may get a special kind of botanical name. This will usually include "xylon" and a term indicating its presumed (not necessarily certain) affinity, such as Araucarioxylon (wood similar to that of extant Araucaria or some related genus like Agathis or Wollemia), Palmoxylon (wood similar to that of modern Arecaeae), or Castanoxylon (wood similar to that of modern chinkapin or chestnut tree).

Agathis, commonly known as kauri or dammara, is a genus of evergreen coniferous trees, native to Australasia and Southeast Asia. It is one of three extant genera in the family Araucariaceae, alongside Wollemia and Araucaria (being more closely related to the former). Its leaves are much broader than most conifers. Kauri gum was historically commercially harvested from living New Zealand kauri and from swamp ground.

The order Pinales in the division Pinophyta, class Pinopsida, comprises all the extant conifers. The distinguishing characteristic is the reproductive structure known as a cone produced by all Pinales. All of the extant conifers, such as Araucaria, cedar, celery-pine, cypress, fir, juniper, kauri, larch, pine, redwood, spruce, and yew, are included here. Some fossil conifers, however, belong to other distinct orders within the division Pinophyta.

Multiple molecular studies indicate this order being paraphyletic with respect to Gnetales, with studies recovering Gnetales as either a sister group to Pinaceae or being more derived than Pinaceae but sister to the rest of the group.