Family Proteaceae.
Proteaceae consists of around 75 genera (64 – 83) with about 1,700 species.
Australia has 47 genera with almost 1100 species.
Well known genera in Australia include Macadamia, Banksia and Grevillea.
Features are very variable among the genera and the following is a general description.
Evergreen plants vary from prostrate or erect shrubs to large trees.
The bark has small nodules (lenticels).
Leaves are mostly alternately arranged and in a spiral.
They may or may not be on a stalk.
There are no stipules and the base of the petiole may be swollen.
Leaves are tough and usually simple but can be variously lobed or compound.
The margins can be smooth, or have sharp or blunt teeth.
Veins can be pinnate, palmate or parallel.
Many have complex inflorescences sometimes referred to as conflorescences.
Solitary flowers are uncommon and some are in pairs.
Tightly clustered flowers can be in an umbel, a spike or a cone-like head.
Bracts are common and are sometimes large and coloured.
Flowers in most are bisexual with parts in 4’s.
There is often a hypogynous or nectiferous disc.
It can be a continuous or partial ring or in 4 (2 or 3) lobes that are fleshy or scale-like.
It lies outside the stamens, and when lobed they alternate with the tepals.
The receptacle may be enlarged into an androphore or gynophore.
There are 4 (3 – 8) tepals that are commonly fused into a long, narrow tube.
In some genera 3 tepals are joined and the free one holds the style.
The enlarged, cap-like tips of the tepals hold the anthers.
The perianth can be regular or bilaterally symmetric and may be coloured.
The 4 stamens, opposite the tepals, are usually all fertile but some may be infertile staminodes.
The filaments are commonly partly or wholly fused to the tepals, rarely free.
The basifixed anthers mostly open inwards via long slits.
The connective tissue between the anther sacs may have an appendage.
There is a superior ovary with 1 locule with 1 to many ovules.
The ovary often has long hairs on it.
It may be on the receptacle or raised on a gynophore.
There is a single, long style with the stigma.
There is often a pollen presenter – an expanded area below or around the stigma.
In flowers that start with totally fused tepals the tube may split as the flower grows.
In young flowers the style lies in the tube with the stigma and pollen presenter among the anthers.
When pollen is released it attaches to the pollen presenter from where it is picked up by pollinators.
As the style elongates the tepal tube splits along one side and the style bends then escapes from the tube.
The fruit are variable – dehiscent or indehiscent and dry or fleshy.
They can be a follicle, drupe or nut.
Fruit of adjacent flowers in an inflorescence may combine to form a compound fruit.
Seeds can be flat or round and often have wings.
Honeyeaters are common pollinators as well as insects and small marsupials.
The family is divided into subfamilies:
Subfamily Proteoideae is divided into 4 tribes then subtribes. Genera include Protea and Leucadendron.
Subfamily Grevilleoideae is also divided into 4 tribes then subtribes. Genera include Banksia,
Buckinghamia, Alloxylon, Stenocarpus, Hakea, Grevillea, Macadamia and Telopea.
The other small subfamilies are Bellendenoideae, Persoonioideae and Symphionematoideae.
J.F.
