Libocedrus austrocaledonica

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Libocedrus austrocaledonica
Systematics
Subdivision : Seed plants (Spermatophytina)
Class : Coniferopsida
Order : Conifers (Coniferales)
Family : Cypress family (Cupressaceae)
Genre : Scaled Cedars ( Libocedrus )
Type : Libocedrus austrocaledonica
Scientific name
Libocedrus austrocaledonica
Brongn. & Gris

Libocedrus austrocaledonica is an evergreen conifer from the genus of the common cedar ( Libocedrus ). The range of the species lies in New Caledonia , whereby it is mostly limited to the south of the island. There it grows in forests with high annual rainfall on higher mountains. The species is not used and not cultivated outside of botanical gardens.

description

Habitus

Libocedrus austrocaledonica forms shrubs or small trees that reach a height of 2 to 4, rarely even 6 meters. The trunks have a diameter of up to 10 centimeters. The bark is reddish brown, rough, scaly and comes off in thin, fibrous strips and plates. Only a few, thin, spreading branches are formed, the more numerous leafy branches are almost horizontal. This gives young trees a narrow, conical crown, while shrubs are irregularly shaped. The branches are arranged in the shape of a fern frond. The outermost branches, completely covered by leaves, are arranged opposite each other, about the same length, but shorten towards the end of the leafy main branch.

leaves

The leaves are opposite to each other. On the main branches they run down long, on the outer branches at the base they are fused, scale-shaped and clearly two-shaped. The surface leaves are narrow, the visible part is 1 to 2 millimeters long, rhombic-pointed, keeled, pressed and at the base partly by the significantly larger, 3 to 6 sometimes up to 7 millimeters long and 1.5 to 3 millimeters wide, protruding and covers flattened edge sheets on both sides.

Cones and seeds

The pollen cones stand individually at the ends of the branches. They are ovate-elongated, 5 to 8 millimeters long with a diameter of 2 to 2.5 millimeters. The 16 to 24 microsporophylls grow cross-opposite. They are shield-shaped with a sharp tip, slightly keeled, with entire margins and have four small, yellow, abaxial pollen sacs. The seed cones stand at the ends of flattened branches, lignify within one growth period and reach lengths of 10 to 12 millimeters. One or two light brown, egg-shaped, elongated, 5 to 6 millimeters long and 2.5 millimeters wide, slightly flattened seeds with a pointed to two-columnar end are formed per cone . The seeds have two opposite, thin-skinned wings, the smaller one forms a strip about 1 millimeter wide, the larger is yellowish brown, oval-elongated, 6 to 8 millimeters long and 2.5 to 3 millimeters wide.

Distribution and location requirements

The natural range of Libocedrus austrocaledonica is on New Caledonia in the southern province and on Mt. Paéoua in the northern province . The species grows in the low rainforest on exposed ridges of the higher mountains at altitudes of 750 to 1400 meters. Where it grows along with falcatifolium taxoides , neocallitropsis , various stone species of yew ( Podocarpus spp.), Prumnopitys ferruginoides and sometimes Araucaria Humboldtensis , next to angiosperms as representatives of the myrtle family (Myrtaceae), members of the genus trimenia and family Winteraceae . The undergrowth usually consists of ferns, mosses and lichens. The soils are very rich in humus and very acidic, but the species avoids ultramafic rocks. At altitudes over 1000 meters, annual precipitation amounts of over 3500 millimeters are reached and the vegetation lies within the cloud cover for most of the time. The temperatures at this altitude are significantly lower than at sea level.

Danger

In the Red List of the IUCN is libocedrus austrocaledonica out ( "Near Threatened") at risk as low. The range is small, but there is no evidence of a decline in the species. If the populations at Mt. Paéoua are affected by mining or in the south of the island by fire or a change in precipitation conditions, classification as endangered ("Endangered") ) appropriate.

Systematics and research history

Libocedrus austrocaledonica is a kind of genre the libocedrus ( Libocedrus ) in the family of cypress plants (Cupressaceae). It was in 1872 by Adolphe Brongniart , and Jean Antoine Arthur Gris in the Bulletin de la Société Botanique de France first described . The genus name Libocedrus is derived from the Greek libos for “tear” or “drop”, referring to resin droplets emerging, and from cedrus the genus name of the cedar trees . The specific epithet austrocaledonica refers to the main distribution area in southern New Caledonia. In addition to Libocedrus austrocaledonica , the names Libocedrus austro-caledonica , Libocedrus austrocaledonia and Libocedrus austrocaledonicus are also used. In 2001, Alexander Borissowitsch Doweld assigned three species of scaled cedars , Libocedrus yateensis , Libocedrus chevalieri and Libocedrus austrocaledonica , to a separate genus Stegocedrus . However, this classification is not generally accepted, Stegocedrus austrocaledonica is only a synonym of the species.

use

The species is not used, it is not cultivated in botanical gardens with the exception of a few plants.

swell

literature

  • Aljos Farjon: A Handbook of the World's Conifers . tape 1 . Brill, Leiden-Boston 2010, ISBN 90-04-17718-3 , pp. 504-505 .
  • Helmut Genaust: Etymological dictionary of botanical plant names. 3rd, completely revised and expanded edition. Nikol, Hamburg 2005, ISBN 3-937872-16-7 , p. 340 (reprint from 1996).

Individual evidence

  1. ↑ a b c d e f Aljos Farjon: A Handbook of the World's Conifers , Volume 1, p. 504
  2. ↑ a b Libocedrus austrocaledonica in the Red List of Threatened Species of the IUCN 2012. Posted by: P. Thomas, 2010. Accessed on January 23, 2013.
  3. ↑ a b Libocedrus austrocaledonia. In: Germplasm Resources Information Network (GRIN). United States Department of Agriculture, accessed January 23, 2013 .
  4. ↑ To be precise: Etymological dictionary of botanical plant names. P. 340
  5. ↑ Libocedrus austrocaledonicus. In: The Plant List. Retrieved January 23, 2013 .
  6. ↑ Stegocedrus. In: The Plant List. Retrieved January 23, 2013 .
  7. ^ Aljos Farjon: A Handbook of the World's Conifers , Volume 1, p. 505

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