The Proteaceae form a family of flowering plants predominantly distributed in the Southern Hemisphere. The family comprises 83 genera with about 1,660 known species. Australia and South Africa have the greatest concentrations of diversity. Together with the Platanaceae (plane trees), Nelumbonaceae (the sacred lotus) and in the recent APG IV system the Sabiaceae, they make up the order Proteales. Well-known Proteaceae genera include Protea, Banksia, Embothrium, Grevillea, Hakea, and Macadamia. Species such as the New South Wales waratah (Telopea speciosissima), king protea (Protea cynaroides), and various species of Banksia, Grevillea, and Leucadendron are popular cut flowers. The nuts of Macadamia integrifolia are widely grown commercially and consumed, as are those of Gevuina avellana on a smaller scale.
Etymology The name Proteaceae was adapted by Robert Brown from the name Proteae coined in 1789 for the family by Antoine Laurent de Jussieu, based on the genus Protea, which in 1767, Carl Linnaeus derived from the name of the Greek god Proteus, a deity who was able to change between many forms.
Taxonomy
First described by French botanist Antoine Laurent de Jussieu, the family Proteaceae is a fairly large one, with around 80 genera, but less than 2,000 species. It is recognised by virtually all taxonomists. Firmly established under classical Linnaean taxonomy, it is also recognised by the cladistics-based APG and APG II systems. It is placed in the order Proteales, whose placement has itself varied. A classification of the genera within Proteaceae was made by Lawrie Johnson and Barbara Briggs in their influential 1975 monograph "On the Proteaceae: the evolution and classification of a southern family", until it was largely superseded by the molecular studies of Peter H. Weston and Nigel Barker in 2006. Proteaceae are now divided into five subfamilies: Bellendenoideae, Persoonioideae, Symphionematoideae, Proteoideae and Grevilleoideae. In 2008 Mast and colleagues updated Macadamia and related genera in tribe Macadamieae. Furthermore, Orites megacarpus was found not to be within the genus Orites, nor in the tribe Roupaleae, instead in the tribe Macadamieae, hence given the new species name Nothorites megacarpus. The full arrangement, according to Weston and Barker (2006) with the updates to genera from Mast et al. (2008), is as follows:
Family Proteaceae Subfamily Bellendenoideae Bellendena Subfamily Persoonioideae Tribe Placospermeae Placospermum Tribe Persoonieae Persoonia Subfamily Symphionematoideae Agastachys — Symphionema Subfamily Proteoideae incertae sedis Eidothea — Beauprea — Beaupreopsis — Dilobeia — Cenarrhenes — Franklandia Tribe Conospermeae Subtribe Stirlingiinae Stirlingia Subtribe Conosperminae Conospermum — Synaphea Tribe Petrophileae Petrophile — Aulax Tribe Proteeae Protea — Faurea Tribe Leucadendreae Subtribe Isopogoninae Isopogon Subtribe Adenanthinae Adenanthos Subtribe Leucadendrinae Leucadendron — Serruria — Paranomus — Vexatorella — Sorocephalus — Spatalla — Leucospermum — Mimetes — Diastella — Orothamnus Subfamily Grevilleoideae incertae sedis Sphalmium — Carnarvonia Tribe Roupaleae incertae sedis Megahertzia — Knightia — Eucarpha — Triunia Subtribe Roupalinae Roupala — Neorites — Orites Subtribe Lambertiinae Lambertia — Xylomelum Subtribe Heliciinae Helicia — Hollandaea Subtribe Floydiinae Darlingia — Floydia Tribe Banksieae Subtribe Musgraveinae Musgravea — Austromuellera Subtribe Banksiinae Banksia Tribe Embothrieae Subtribe Lomatiinae Lomatia Subtribe Embothriinae Embothrium — Oreocallis — Alloxylon — Telopea Subtribe Stenocarpinae Stenocarpus — Strangea Subtribe Hakeinae Opisthiolepis — Buckinghamia — Hakea — Grevillea — Finschia Tribe Macadamieae Subtribe Macadamiinae Macadamia — Lasjia — Nothorites — Panopsis — Brabejum Subtribe Malagasiinae Malagasia — Catalepidia Subtribe Virotiinae Virotia — Athertonia — Heliciopsis Subtribe Gevuininae Cardwellia — Euplassa — Gevuina — Bleasdalea — Hicksbeachia — Kermadecia
Description
The genera of Proteaceae are highly varied, with Banksia in particular providing a striking example of adaptive radiation in plants. This variability makes it impossible to provide a simple, diagnostic identification key for the family, although individual genera may be easily identified.
Proteaceae range from prostrate shrubs to tall forest trees of 40 m (130 ft) in height, and are usually of medium height or low or perennial shrubs, except for some Stirlingia species that are herbs. Some species are facultatively deciduous (Embothrium coccineum), rarely acaulescent, the cauline portion of the collar is often thickened (lignotuber). Indumentum of three-celled hairs, sometimes glandular, rarely absent, the apical cell is usually elongated, acute, sometimes equally or unequally bifid. Leaves rarely aromatic, usually alternate, and in a spiral, rarely opposed, or verticilate; coriaceous, rarely fleshy or spinescent, simple or compound (imparipinate, imparibipinate or rarely palmate or digitate with pinnatisect segments), entire edge to (3-)pinnatisect (giving a fern-like aspect); rarely divided dichotomously, often remotely toothed, crenate or serrated, seated or stalked; the petiole frequently with a swollen base but rarely sheathed (sometimes in Synaphea), without stipules; pinnate sometimes palmate or parallel venation, brochidodromous or reduced to a single prominent vane, vernation normally conduplicate; anisophylly often occurs during the different growth periods; leaf blade dorsiventral, isobilateral or centred; mesophyll tissue usually with sclerenchymatous idioblasts, rare secretory cavities. Brachy-paracytic stomata (laterocytic in Bellendena). Plant stems with two types of radii, wide and multi-serrated or narrow and uni-serrated, phloem stratified or not, trilacunar nodes with three leaf traces (rarely unilacunar with one trace), sclereids frequent; bark with lenticels frequently horizontally enlarged, cork cambium present, usually superficial. Roots lateral and short, often grouped in bundles (proteoid roots) with very dense root hairs, rarely with mycorrhiza.
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