Rarity is relative. What may be strange for me may not work for another individual. However, in the plant kingdom, there are definitely some species that most people would recognise as highly unusual. Some of them can be found below:
Rafflesia arnoldii
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Hydnora africana
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Dracunculus vulgaris
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Amorphophallus
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Wollemia nobilis
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Welwitschia mirabilis
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Drakaea glyptodon
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Wolffia angusta
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Orchis simia
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Caleana major
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Physalis alkekengi
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Dicentra cucullari
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Ophrys
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Leucospermum
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Hoya lasiantha
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