Leaflet (botany)
A leaflet (occasionally called foliole) in botany is a leaf-like part of a compound leaf.[1] Though it resembles an entire leaf, a leaflet is not borne on a main plant stem or branch, as a leaf is, but rather on a petiole or a branch of the leaf.[2]
Compound leaves are common in many plant families and they differ widely in morphology.[3] The two main classes of compound leaf morphology are palmate and pinnate. For example, a hemp plant has palmate compound leaves,[4] whereas some species of Acacia have pinnate leaves.[5]
The ultimate division (or leaflet) of a compound leaf, or a pinnate subdivision of a multipinnate leaf is called a pinnule or pinnula.[6]
-
Pinnate leaf of a legume with 10 leaflets
-
Mimosa pudica folding leaflets inward.
The different shapes of leaflets can be described as elliptical, oval, lanceolate or other shapes. Leaflets can be divided in different ways; for example, unipinnate, which is a simple pinnate with leaflets, where no more divisions occur (e.g. Cassia), bipinnate, which has secondary leaflets, with each leaflet dividing into another set of leaflets (e.g. Acacia) and tripinnate, where further division occurs after the secondary leaflets (e.g. Moringa).[7]
It can be difficult to tell the difference between a leaf and a leaflet, because leaflets look like a small leaf, but are actually a segment of a compound leaf and are also not attached to the stem.[8] Leaflets do not ever have axillary buds.[9]
Etymology
Leaflet includes the words leaf and let. Leaf originates from an Old English word that reflects a plant’s foliage. The suffix -“let”, comes from a Middle English and Old French word, meaning lesser or smaller of something. Leaflet therefore means a "petite version of a typical leaf structure”.[7]
See also
Page Module:Side box/styles.css has no content.Page Template:Sister project/styles.css has no content.
References
Page Template:Reflist/styles.css has no content.
- ^ Page Module:Citation/CS1/styles.css has no content.Walters, Dirk R.; Keil, David J. (1996). Vascular Plant Taxonomy (4th ed.). Dubuque, Iowa, USA: Kendall Hunt Publishing Company. p. 33. ISBN 978-0-7872-2108-9.
- ^ Page Module:Citation/CS1/styles.css has no content."Types of Leaf Forms". Biology LibreTexts. 16 July 2018. Retrieved 30 March 2021.
- ^ Page Module:Citation/CS1/styles.css has no content.Koch, Garance; Rolland, Gaëlle; Dauzat, Myriam; Bédiée, Alexis; Baldazzi, Valentina; Bertin, Nadia; Guédon, Yann; Granier, Christine (2018). "Are compound leaves more complex than simple ones? A multi-scale analysis". Annals of Botany. 122 (7) (published December 2018): 1173–1185. doi:10.1093/aob/mcy116. ISSN 0305-7364. PMC 6324747. PMID 29982438.
- ^ Page Module:Citation/CS1/styles.css has no content.Balant, Manica; Garnatje, Teresa; Vitales, Daniel; Hidalgo, Oriane; Chitwood, Daniel H. (2024). "Intra-leaf modeling of Cannabis leaflet shape produces leaf models that predict genetic and developmental identities". New Phytologist. 243 (2): 781–796. doi:10.1111/nph.19817. hdl:10261/371797. ISSN 1469-8137.
- ^ Page Module:Citation/CS1/styles.css has no content."Robinia hispida | rose acacia Shrubs/RHS". www.rhs.org.uk. Retrieved 2025-11-23.
- ^ Page Module:Citation/CS1/styles.css has no content."PINNULATE definition and meaning | Collins English Dictionary". www.collinsdictionary.com. 2025-11-17. Retrieved 2025-11-23.
- ^ a b Page Module:Citation/CS1/styles.css has no content."Leaflets - Definition and Examples - Biology Online Dictionary". Biology Articles, Tutorials & Dictionary Online. Retrieved 2025-11-23.
- ^ Page Module:Citation/CS1/styles.css has no content."Difference between Leaf and Leaflet". www.differencebetween.info. 2014-02-06. Retrieved 2025-11-23.
- ^ Page Module:Citation/CS1/styles.css has no content."Plant Morphology: Leaf Type". American Museum of Natural History. Archived from the original on 2025-06-18. Retrieved 2025-11-23.
