Spur (biology)

A spur in botany is a spike, usually part of a flower.

In certain plants, part of a sepal or petal develops into an elongated hollow spike extending behind the flower, containing nectar which is sucked by long-tongued animals (insects, birds or bats). Plants with such structures include Delphinium, Aquilegia, Piperia, and some orchids, such as Gymnadenia. Spurs may be useful in species identification – for example Yadon's piperia cannot be easily distinguished from other Piperia save for the unusually short length of its spur.

In tropical pitcher plants of the genus Nepenthes, the spur is a small appendage at the base of the pitcher lid.

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