''Gyrocarpus americanus'' is a

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

in the ''

Hernandiaceae The Hernandiaceae are a family of flowering plants (angiosperms) in the order Laurales. Consisting of five genera with about 58 known species, they are distributed over the world's tropical areas, some of them widely distributed in coastal areas ...

'' family, with a wide

pantropical A pantropical ("all tropics") distribution is one which covers tropical regions of both hemispheres. Examples of species include caecilians, modern sirenians and the plant genera ''Acacia'' and ''Bacopa''. ''Neotropical'' is a zoogeographic term ...

distribution. Its common names include the helicopter tree, propeller tree, whirly whirly tree, stinkwood or shitwood.

Description

''Gyrocarpus americanus'' is a slender,

deciduous In the fields of horticulture and Botany, the term ''deciduous'' () means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, ...

tree with smooth, grey bark. The tree grows to about 12 m in height. The leaves are spirally arranged, crowded near the ends of the branches, and grow up to 150 × 120 mm in size. They are

ovate Ovate may refer to: * Ovate (egg-shaped) leaves, tepals, or other botanical parts *Ovate, a type of prehistoric stone hand axe *Ovates, one of three ranks of membership in the Welsh Gorsedd *Vates In modern English, the nouns vates () and ova ...

, often 3-lobed, dark green above, paler and greyer below, with velvety surfaces, 3-veined from the base. The veins are yellowish. The cream to yellowish-green flowers grow in compact heads and have an unpleasant smell. The fruit is a woody nut with two long thin wings that help in wind dispersal. The winged fruit and the smell of the flowers have given the tree its various common names.

Taxonomy

Subspecies

* ''G. a. africanus'' Kubitzki (Africa) * ''G. a. americanus'' Jacq. ( East Africa,

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

Malesia Malesia is a biogeographical region straddling the Equator and the boundaries of the Indomalayan and Australasian realms, and also a phytogeographical floristic region in the Paleotropical Kingdom. It has been given different definitions. Th ...

, northern Australia,

Melanesia Melanesia (, ) is a subregion of Oceania in the southwestern Pacific Ocean. It extends from Indonesia's New Guinea in the west to Fiji in the east, and includes the Arafura Sea. The region includes the four independent countries of Fiji, Va ...

Polynesia Polynesia () "many" and νῆσος () "island"), to, Polinisia; mi, Porinihia; haw, Polenekia; fj, Polinisia; sm, Polenisia; rar, Porinetia; ty, Pōrīnetia; tvl, Polenisia; tkl, Polenihia (, ) is a subregion of Oceania, made up of ...

, and South and

Central America Central America ( es, América Central or ) is a subregion of the Americas. Its boundaries are defined as bordering the United States to the north, Colombia to the south, the Caribbean Sea to the east, and the Pacific Ocean to the west. ...

) * ''G. a. glaber'' Kubitzki (

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

) Several other subspecies have been described. Kubitzki distinguished eight – three in Madagascar, one each in tropical West and East Africa, one in tropical Australia, and one in Malesia, with the eighth being the typical subspecies ''G. a. americanus'' originating in the Palaeotropics and reaching the

Neotropics The Neotropical realm is one of the eight biogeographic realms constituting Earth's land surface. Physically, it includes the tropical terrestrial ecoregions of the Americas and the entire South American temperate zone. Definition In bioge ...

by trans-Pacific dispersal. Most of these are rarely collected or are not recognised. Moreover, the

monophyly In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

of ''G. americanus'' remains unclear; the African species ''G. angustifolius'' and ''G. hababensis'' may lie within it.Michalak et al. (2010).

References

Inline citations

Sources referenced

* *

External links

* * {{Taxonbar, from=Q5625456 Hernandiaceae Flora of Africa Flora of Madagascar Flora of India (region) Flora of Malesia Flora of Christmas Island Flora of Western Australia Flora of the Northern Territory Flora of Queensland Flora of South America Pantropical flora