Taxonomy of Banksia

As with other flowering plants, the taxonomy of Banksia has traditionally been based on anatomical and morphological properties of the Banksia flower, fruiting structure and seed, along with secondary characteristics such as leaf structure and growth habit. Increasingly, molecular evidence from DNA is providing important new insights into relationships within the genus and between this and other genera in the Proteaceae.

The genus is placed in family Proteaceae, subfamily Grevilleoideae, tribe Banksieae and subtribe Banksiinae. The most recent complete revision is that published in Alex George's 1999 monograph for the Flora of Australia book series; this recognises two subgenera, three sections, 13 series, 77 species, 6 subspecies and 18 varieties, and treats the traditionally related genus Dryandra as separate but closely related. Recent molecular cladistic analyses have provided an alternative view in which Dryandra is shown to be nested inside, and hence should be included within, Banksia. This interpretation has been controversial in some circles, and is not universally accepted.

Banksia (in the traditional sense, not including Dryandra), is a genus of around 80 species in the plant family Proteaceae. An iconic Australian wildflower and popular garden plant, they are easily recognised by their characteristic flower spikes and fruiting "cones". They grow in forms varying from prostrate woody shrubs to trees up to 35 metres tall, and occur in all but the most arid areas of Australia. As heavy producers of nectar, they are important sources of food for nectariferous animals such as honeyeaters and honey possums, and they are of economic importance to the nursery and cut flower industries. However they are threatened by a number of processes, including land clearing, frequent burning, and disease; and a number of species are rare and endangered.

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