Australian Journal of Botany Australian Journal of Botany Society
Southern hemisphere botanical ecosystems

Enantiomorphy in Banksia (Proteaceae): flowers and fruits

A. Renshaw A and S. Burgin A B

A School of Natural Sciences, College of Health and Science, University of Western Sydney, Locked Bag 1797, South Penrith DC, NSW 1797, Australia.

B Corresponding author. Email:

Australian Journal of Botany 56(4) 342-346
Submitted: 19 April 2007  Accepted: 3 April 2008   Published: 16 June 2008


There is a history of discrepancy in the interpretation of floral symmetry in the genus Banksia L.f. The variation arises not just from the potential nuances of symmetry terminology, as variation is also found in the diagrams that describe it. This paper clarifies the issue of the orientation of the ovaries within a Banksia unit inflorescence. Dissection of 2400 flowers in situ from four Banksia species has revealed the Banksia unit inflorescence to be enantiomorphic (having left-right asymmetry) due to the orientation of the ovaries. The asymmetry of the ovary and its pronounced development of the anterior side in fruit formation means that fruits are also readily distinguished as having arisen from either a left- or right-handed flower.


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