Agathis
| Agathis Temporal range:
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|---|---|
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| Te Matua Ngahere, an Agathis australis (New Zealand kauri) | |
Scientific classification 
| |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Gymnospermae |
| Division: | Pinophyta |
| Class: | Pinopsida |
| Order: | Araucariales |
| Family: | Araucariaceae |
| Genus: | Agathis Salisb., 1807 |
| |
| Distribution of Agathis species | |
| Synonyms[1] | |
Agathis, commonly known as kauri or dammara, is a genus of 22 species of evergreen tree. The genus is part of the ancient conifer family Araucariaceae, a group once widespread during the Jurassic and Cretaceous periods, but now largely restricted to the Southern Hemisphere except for a number of extant Malesian Agathis.[1][2]
Description
 | This section needs additional citations for verification. (June 2021) |
Mature kauri trees have characteristically large trunks, with little or no branching below the crown. In contrast, young trees are normally conical in shape, forming a more rounded or irregularly shaped crown as they achieve maturity.[3]
The bark is smooth and light grey to grey-brown, usually peeling into irregular flakes that become thicker on more mature trees. The branch structure is often horizontal or, when larger, ascending. The lowest branches often leave circular branch scars when they detach from the lower trunk.
The juvenile leaves in all species are larger than the adult, more or less acute, varying among the species from ovate to lanceolate. Adult leaves are opposite, elliptical to linear, very leathery and quite thick. Young leaves are often a coppery-red, contrasting markedly with the usually green or glaucous-green foliage of the previous season.
The male pollen cones appear usually only on larger trees after seed cones have appeared. The female seed cones usually develop on short lateral branchlets, maturing after two years. They are normally oval or globe shaped.
Seeds of some species are attacked by the caterpillars of Agathiphaga, some of the most primitive of all living moths.
Uses
Various species of kauri give diverse resins such as kauri gum. The timber is generally straight-grained and of fine quality with an exceptional strength-to-weight ratio and rot resistance, making it ideal for yacht hull construction. The wood is commonly used in the manufacture of guitars and ukuleles due to its low density and relatively low price of production. It is also used for some Go boards (goban). The uses of the New Zealand species (A. australis) included shipbuilding, house construction, wood panelling, furniture making, mine braces, and railway sleepers. Due to the hard resin of the wood, it was the traditionally preferred material used by Māori for wooden weapons, patu aruhe (fernroot beaters) and barkcloth beaters.[4]
Evolutionary history
Within Araucariaceae, Agathis is more closely related to Wollemia than to Araucaria. The oldest fossils currently confidently assignable to Agathis are those of Agathis immortalis from the Salamanca Formation of Patagonia, which dates to the Paleocene, approximately 64.67–63.49 million years ago. Agathis-like leaves are also known from the slightly older Lefipán Formation of the same region, which date to the very end of the Cretaceous.[5]
Species list
- Accepted species[1]
| Image | Scientific name | Common Name | Distribution |
|---|---|---|---|
.jpg) |
Agathis atropurpurea | black kauri, blue kauri | Queensland, Australia |
 |
Agathis australis | kauri, New Zealand kauri | North Island, New Zealand |
 |
Agathis borneensis | western Malesia, Borneo | |
 |
Agathis dammara | Philippines, Sulawesi, Maluku Islands | |
| Agathis flavescens | Peninsular Malaysia | ||
| Agathis jurassica | |||
.jpg) |
Agathis kinabaluensis | Borneo | |
| Agathis labillardieri | New Guinea | ||
 |
Agathis lanceolata | New Caledonia | |
| Agathis lenticula | Borneo | ||
 |
Agathis macrophylla (syn. A. vitiensis) | Pacific kauri, dakua | Fiji, Vanuatu, Solomon Islands |
 |
Agathis microstachya | bull kauri | Queensland, Australia |
| Agathis montana | New Caledonia | ||
 |
Agathis moorei | white kauri | New Caledonia |
| Agathis orbicula | Borneo | ||
 |
Agathis ovata | New Caledonia | |
 |
Agathis robusta | Queensland kauri | Queensland, Australia; New Guinea |
| Agathis silbae | Vanuatu | ||
| Agathis spathulata | New Guinea kauri | Papua New Guinea | |
| Agathis zamunerae | Patagonia, South America Argentina |
- Formerly included[1]
Moved to Nageia
- Agathis motleyi - Nageia motleyi
- Agathis veitchii - Nageia nagi
Gallery
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Te Matua Ngahere, an A. australis in Waipoua Forest, the oldest (and 2nd largest) tree in New Zealand -
Trunk of the Yakas kauri (7th largest) -
Agathis lanceolata -
Agathis ovata -
Agathis macrophylla -
Agathis robusta -
Agathis borneensis -
Agathis australis male pollen cone -
Agathis australis seed -
Agathis australis cone -
Agathis australis leaves and cones
References
- ^ a b c d Kew World Checklist of Selected Plant Families
- ^ de Laubenfels, David J. 1988. Coniferales. P. 337–453 in Flora Malesiana, Series I, Vol. 10. Dordrecht: Kluwer Academic.
- ^ Whitmore, T.C. 1977. A first look at Agathis. Tropical Forestry Papers No. 11. University of Oxford Commonwealth Forestry Institute.
- ^ Neich, Roger (1996). "New Zealand Maori Barkcloth and Barkcloth Beaters". Records of the Auckland Institute and Museum. 33: 111–158. ISSN 0067-0464.
- ^ Escapa, Ignacio H.; Iglesias, Ari; Wilf, Peter; Catalano, Santiago A.; Caraballo‐Ortiz, Marcos A.; Rubén Cúneo, N. (August 2018). "Agathis trees of Patagonia's Cretaceous‐Paleogene death landscapes and their evolutionary significance". American Journal of Botany. 105 (8): 1345–1368. doi:10.1002/ajb2.1127. ISSN 0002-9122. PMID 30074620. S2CID 51908977.
External links
