''Aextoxicon punctatum'', the sole species of genus ''Aextoxicon'' and family Aextoxicaceae, is a
dioecious tree
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are ...
native to southern
Chile
Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east a ...
and
Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
. Commonly known as the ''olivillo'' or ''aceitunillo'', it is a large
evergreen
In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This also pertains to plants that retain their foliage only in warm climates, and contrasts with deciduous plants, whic ...
tree native to the forests of the
Valdivian temperate rain forests
The Valdivian temperate forests (NT0404) is an ecoregion on the west coast of southern South America, in Chile and Argentina. It is part of the Neotropical realm. The forests are named after the city of Valdivia. The Valdivian temperate rainforest ...
and
Magellanic subpolar forests
The Magellanic subpolar forests () are a terrestrial ecoregion of southernmost South America, covering parts of southern Chile and Argentina, and are part of the Neotropical realm. It is a temperate broadleaf and mixed forests ecoregion, and ...
of southern Chile's
Pacific
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...
coast, where it forms is a
canopy
Canopy may refer to:
Plants
* Canopy (biology), aboveground portion of plant community or crop (including forests)
* Canopy (grape), aboveground portion of grapes
Religion and ceremonies
* Baldachin or canopy of state, typically placed over an ...
tree in the
broadleaf forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...
s. It can reach 15 m tall.
The
APG system
The APG system (Angiosperm Phylogeny Group system) of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved A ...
(1998) and the
APG II system
The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Gr ...
(2003) left the family Aextoxicaceae unplaced in the
core eudicots
The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons.
Traditionally they were called tricolpates or non-magnoliid dicots ...
. It has since been included in the order
Berberidopsidales
Berberidopsidales is an order of Southern Hemisphere woody flowering plants. The name is newly accepted in the APG III system of plant taxonomy. APG II system, of 2003, mentions the possibility of recognizing the order, as comprising the familie ...
.
The genus was formerly often included in the family
Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as '' Euphorbia paralias'', are herbs, but some, ...
.
Description
''Aextoxicon punctatum'' is a large tree often found in the
canopy
Canopy may refer to:
Plants
* Canopy (biology), aboveground portion of plant community or crop (including forests)
* Canopy (grape), aboveground portion of grapes
Religion and ceremonies
* Baldachin or canopy of state, typically placed over an ...
or emergent. It has opposite leaves with dark green coloration on the top and lighter green below, and is covered in rusty peltate scales. The flowers are
actinomorphic
Floral symmetry describes whether, and how, a flower, in particular its perianth, can be divided into two or more identical or mirror-image parts.
Uncommonly, flowers may have no axis of symmetry at all, typically because their parts are spirall ...
and unisexual, in hanging
racemes
A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...
. The flowers have 5
sepals and 5
petals
Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually ...
. Male flowers have 5
stamens
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10
Morphology and terminology
A stamen typically consists of a stalk called the filame ...
opposite the sepals while female flowers have two
carpels that fuse to form a bilocular ovary. The
fruit
In botany, a fruit is the seed-bearing structure in flowering plants that is formed from the ovary after flowering.
Fruits are the means by which flowering plants (also known as angiosperms) disseminate their seeds. Edible fruits in particu ...
is a single seeded
drupe that resembles an olive, thus giving the plant its common name.
Distribution and habitat
''Aextoxicon punctatum'' is found in Chile, usually in damp places from the
Bosque de Fray Jorge National Park
A bosque ( ) is a type of gallery forest habitat found along the riparian flood plains of stream and river banks in the southwestern United States. It derives its name from the Spanish word for ' woodlands'.
Setting
In the predominantly ari ...
southwards to the
Chiloé Archipelago
The Chiloé Archipelago ( es, Archipiélago de Chiloé, , ) is a group of islands lying off the coast of Chile, in the Los Lagos Region. It is separated from mainland Chile by the Chacao Channel in the north, the Sea of Chiloé in the east and t ...
, also in the Valdivian forest and Magellanic forests of the southern Pacific coast. In Argentina it is present in the middle reaches of the
Rio Negro valley, being invasive on the island of
Choele Choel
Choele Choel is the capital of the department of Avellaneda in the Argentine province of Río Negro, and the most important settlement within the ''Valle Medio'' ("Middle Valley") agricultural area of the Río Negro River in Patagonia.
Overv ...
, and it is common in the
Lago Puelo National Park, Chubut.
Uses
The tree is used for its high-quality timber.
[
]
References
External links
''Aextoxicon punctatum'' in Encyclopedia of the Chilean Flora
in L. Watson and M.J. Dallwitz (1992 onwards)
''The families of flowering plants''
Hansen & Rahn: Aextoxicaceae
NCBI Taxonomy Browser: Aextoxicaceae
CSDL: Aextoxicaceae
{{Taxonbar, from1=Q1070232, from2=Q292660
Berberidopsidales
Flora of the Andes
Flora of central Chile
Trees of Chile
Trees of Argentina
Trees of mild maritime climate
Trees of subpolar oceanic climate
Valdivian temperate rainforest
Monotypic eudicot genera
Data deficient plants
Dioecious plants
Taxa named by José Antonio Pavón Jiménez