Nectar spur

Nectar spurs on Aquilegia.
Side view of Tropaeolum majus, a plant with a nectar spur arising from the hypanthium of the flower.

A nectar spur is a hollow extension of a part of a flower. The spur may arise from various parts of the flower: the sepals, petals, or hypanthium, and often contain tissues that secrete nectar (nectaries).[1][2] Nectar spurs are present in many clades across the angiosperms, and are often cited as an example of convergent evolution.[3]

  1. ^ Antoń, Sebastian; Kamińska, Magdalena (2015-11-01). "Comparative floral spur anatomy and nectar secretion in four representatives of Ranunculaceae". Protoplasma. 252 (6): 1587–1601. doi:10.1007/s00709-015-0794-5. ISSN 0033-183X. PMC 4628095. PMID 25772682.
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