Geissapis cristata is an annual herb that grows in certain wetlands in Hong Kong. It seems quite uncommon locally with restricted distribution. The species is characterized by its large bracts with cilia. The bracts probably brought the plant its Chinese name, which means bracts with eyelashes. Personally, I think the bracts are used by the plant to protect the flower buds and other fragile structures from insects and other pests, but I wonder whether the structure would hinder seed dispersal too since the bracts also seems to be covering up the pods. According to
Flora of Hong Kong, the pods have 1-2 segments with each segment 4mm in length. With pods this size, it is possible that the plant depends on anemochory (wind dispersal). Maybe the bracts could prevent the seeds from being blown away when the wind is not strong enough to bring the seeds to a place far away, but further studies are needed to test this hypothesis.
I found a population of
G. cristata in a piece of wetland near the seashore in Sai Kung. The location is under heavy pressure for development and this population may very likely be completely wiped out if the development plan is implemented. It occurs to me that wetlands, with its flat nature, is extremely vulnerable to development, and sadly the government hasn't done much to protect them. It is really a pity to see that more and more wetlands with high ecological value are replaced by residential flats and houses. I really hope to see more laws and regulations targeting the protection of wetlands such as this one in the future, or else, rare wetland species such as
G. cristata will very likely become locally extinct in coming years. Here are some photos of
G. cristata taken in November.
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| Population |
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| Leaves |
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| Yellowish flowers |
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| Bracts |
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