Hapaxanth

A hapaxanth is a plant species whose individuals flower only once in their lifetimes and die subsequently. Other terms with the same meaning are semelparous and monocarpic. The term was first used by Alexander Braun.

This term is used for plants that only have one flowering event and then die. It is used most often in conjunction with describing some of the taxa of Arecaceae (palms) and some species of bamboo, but rarely used otherwise. Many annuals flower over a period of time and can have flowers and seeds on the same plant at the same time, thus they are not hapaxanthic, because flowering does not lead to death. A similar term is monocarpic, for a plant that bears fruit once and then dies. A related term is pleonanthic, again used with Arecaceae (palms) and some bamboos for stems that flower more than once. Its antonym is often given as pollakanth, although pleonanth is also seen.

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