''Gyrocarpus americanus'' is a flowering plant in the '' Hernandiaceae'' family, with a wide pantropical distribution. Its common names include the helicopter tree, propeller tree, whirly whirly tree, stinkwood or shitwood.

Description

''Gyrocarpus americanus'' is a slender, deciduous tree with smooth, grey

bark Bark may refer to: * Bark (botany), an outer layer of a woody plant such as a tree or stick * Bark (sound), a vocalization of some animals (which is commonly the dog) Places * Bark, Germany * Bark, Warmian-Masurian Voivodeship, Poland Arts, ...

. The tree grows to about 12 m in height. The

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are spirally arranged, crowded near the ends of the branches, and grow up to 150 × 120 mm in size. They are ovate, 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 East Africa, Eastern Africa, or East of Africa, is the eastern subregion of the African continent. In the United Nations Statistics Division scheme of geographic regions, 10-11-(16*) territories make up Eastern Africa: Due to the historical ...

, India, Malesia, northern

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

, Melanesia, Polynesia, and

South South is one of the cardinal directions or Points of the compass, compass points. The direction is the opposite of north and is perpendicular to both east and west. Etymology The word ''south'' comes from Old English ''sūþ'', from earlier Pro ...

and Central America) * ''G. a. glaber'' Kubitzki ( Madagascar) 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 The Paleotropical Kingdom (Paleotropis) is a floristic kingdom comprising tropical areas of Africa, Asia and Oceania (excluding Australia and New Zealand), as proposed by Ronald Good and Armen Takhtajan. Part of its flora, inherited from the ancient ...

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