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| Last updated: November 2022 |

The seed is about 1 millimetre (mm) in diameter with undulating surfaces. When the cymose flower head matured, the light brown tiny seeds can be seen half hidden on the top of the flower head. They are dispersed via an explosive mechanism.

This herbaceous plant was first spotted at an open-air carpark next to my apartment block in June 2015. It was not listed in the Singapore Flora checklist published in 2009. In a publication that screened potential of tropical plant species for phytoremediation in Singapore, Fatoua pilosa was one of the plants collected between March 2019 and January 2020 [1]. Someone had asked for the identity of this plant in a local newspaper in November 2021. In the iNaturalist website viewed on 9 November 2022, there was just 1 sighting of Fatoua pilosa in May 2019 but 11 sightings of Fatoua villosa with the first sighting dated January 2020.

Some reports such as the nzflora website has considered Fatoua pilosa and Fatoua villosa as the same plant. However, other websites such as the Plants of the World Online and the Flora of China have treated the 2 names as different species. More information on the complexity of this genus is available at the website by Arthur Lee.

Based on the description in the Flora of China website, the leaf of Fatoua pilosa is "not decurrent on petiole" while that of Fatoua villosa is "decurrent on petiole". Decurrent means that the leaf blades partly wrap or have wings around the petiole. It is quite clear that the leaves of the herb I saw were not decurrent on petiole. However, based on the information from a local publication in 2020 [2], this plant should be named Fatoua villosa.

Interestingly, the plant can be propagated by stem cutting. Simply cut a matured branch and stick it in the soil will do the trick.

Reference:

[1] Wang Y, Tan SN, Yusof MLM, Ghosh S, Lam YM. Assessment of heavy metal and metalloid levels and screening potential of tropical plant species for phytoremediation in Singapore. Environmental Pollution 2022;295:118681. | Read article |

[2] Choo LM, Yeo RSW, Ho BC, Ong KH, Chen LMJ. Additions to the Flora of Singapore: New and overlooked records of naturalised plant species (4). Nature in Singapore 2020;13:39-45. | Read article |

The table below compared some features of the two closely related plant based on the information from the Flora of China website.

| University of Florida | Flora of North America | TN-KY Plant Atlas | Australian Tropical Rainforest Plants | Missouri Plants |

[2017] Su SY, Xue JJ, Yang GY, Lei C, Hou AJ. New cytotoxic alkylated chalcones from Fatoua villosa. Chem Biodivers 2017;14(6). | Read abstract |