Banksia sessilis var. cordata
Encyclopedia
Banksia sessilis var. cordata is a variety of Banksia sessilis (Parrot Bush), with unusually large leaves and flower heads. It is a rare variety that is restricted to the extreme south-west corner of Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

.

Description

This variety is similar to other varieties of B. sessilis, but has larger leaves; these may be up to six centimetres long and four centimetres wide in this variety, whereas in B. sessilis var. sessilis
Banksia sessilis var. sessilis
Banksia sessilis var. sessilis is the most populous and most widespread variety of Banksia sessilis .-Description:The leaves of this variety are larger than those of B. sessilis var. cygnorum but smaller than those of B. sessilis var. cordata. It differs from B. sessilis var...

 they are commonly two to three centimetres long. The leaves of this variety are also a darker green than the other varieties, and its flower heads are generally larger.

Taxonomy

This variety was first published as a variety of Dryandra floribunda (now B. sessilis) by Carl Meissner
Carl Meissner
Carl Daniel Friedrich Meissner was a Swiss botanist.Born in Bern, Switzerland on 1 November 1800, he was christened Meisner but later changed the spelling of his name to Meissner. For most of his 40 year career he was Professor of Botany at University of Basel...

 in the second volume of
Plantae Preissianae, published in 1848. It was based on a type specimen collected by James Drummond
James Drummond (botanist)
James Drummond was a botanist and naturalist who was an early settler in Western Australia.-Early life:...

; interestingly, this specimen was said to have been collected at the Swan River
Swan River (Western Australia)
The Swan River estuary flows through the city of Perth, in the south west of Western Australia. Its lower reaches are relatively wide and deep, with few constrictions, while the upper reaches are usually quite narrow and shallow....

, where this variety does not now occur. Meissner did not explicitly give an etymology
Etymology
Etymology is the study of the history of words, their origins, and how their form and meaning have changed over time.For languages with a long written history, etymologists make use of texts in these languages and texts about the languages to gather knowledge about how words were used during...

 for the varietal epithet, but referred to the leaves as
cordatis, Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...

 for "heart-shaped", and this is now universally recognised as the source of the name.

In 1870, George Bentham
George Bentham
George Bentham CMG FRS was an English botanist, characterized by Duane Isely as "the premier systematic botanist of the nineteenth century".- Formative years :...

 published what is now recognised as a synonym of this variety, as
D. floribunda var. major. Bentham's taxon was based on a specimen collected at Cape Naturaliste
Cape Naturaliste
Cape Naturaliste is a headland in the south western region of Western Australia at the western edge of the Geographe Bay. It is the northernmost point of the Leeuwin-Naturaliste Ridge which was named after the cape...

 by Augustus Oldfield. He also attributed to this variety a painting of
D. floribunda that appeared in Curtis's Botanical Magazine
Curtis's Botanical Magazine
The Botanical Magazine; or Flower-Garden Displayed, is an illustrated publication which began in 1787. The longest running botanical magazine, it is widely referred to by the subsequent name Curtis's Botanical Magazine....

in 1813.

Dryandra floribunda having been overturned in favour of Dryandra sessilis in 1924, in 1996 Alex George
Alex George
Alexander Segger George is a Western Australian botanist. He is the authority on the plant genera Banksia and Dryandra...

 transferred var.
cordata from the former to the latter species. The current name changed again in 2007, when Austin Mast
Austin Mast
Austin R. Mast is a research botanist. Born in 1972, he obtained a Ph.D. from the University of Wisconsin–Madison in 2000. He is currently an associate professor within the Department of Biological Science at Florida State University , and has been director of FSU's since August 2003.One of his...

 and Kevin Thiele
Kevin Thiele
Kevin R. Thiele is curator of the Western Australian Herbarium. His research interests include the systematics of the plant families Proteaceae, Rhamnaceae and Violaceae, and the conservation ecology of grassy woodland ecosystems...

 transferred
Dryandra
Dryandra
Banksia ser. Dryandra is a series of 94 species of shrub to small tree in the plant genus Banksia. It was considered a separate genus named Dryandra until early 2007, when it was merged into Banksia on the basis of extensive molecular and morphological evidence that Banksia was paraphyletic with...

into Banksia
Banksia
Banksia is a genus of around 170 species in the plant family Proteaceae. These Australian wildflowers and popular garden plants are easily recognised by their characteristic flower spikes and fruiting "cones" and heads. When it comes to size, banksias range from prostrate woody shrubs to trees up...

; thus the variety's current full name is Banksia sessilis var. cordata (Meisn.) A.R.Mast & K.R.Thiele.

Distribution and habitat

B. sessilis var. cordata occurs only in the Warren region
Warren (biogeographic region)
Warren, also known as Karri Forest Region and the Jarrah-Karri forest and shrublands ecoregion, is a biogeographic region in southern Western Australia. Located in the southwest corner of Western Australia between Cape Naturaliste and Albany, it is bordered to the north and east by the Jarrah...

 of the Southwest Botanical Province of Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

. It occurs in two disjoint areas: along the west coast between Cape Naturaliste
Cape Naturaliste
Cape Naturaliste is a headland in the south western region of Western Australia at the western edge of the Geographe Bay. It is the northernmost point of the Leeuwin-Naturaliste Ridge which was named after the cape...

 and Cape Leeuwin
Cape Leeuwin
Cape Leeuwin is the most south-westerly mainland point of the Australian Continent, in the state of Western Australia.A few small islands and rocks, the St Alouarn Islands, extend further to the south. The nearest settlement, north of the cape, is Augusta. South-east of Cape Leeuwin, the coast...

; and along the south coast between Point D'Entrecasteaux and Denmark
Denmark, Western Australia
Denmark is a town in the Great Southern region of Western Australia, south-south-east of the state capital of Perth. At the 2006 census, Denmark had a population of 2,732.-History:...

. It grows in sand over limestone, amongst coastal heath
Heath (habitat)
A heath or heathland is a dwarf-shrub habitat found on mainly low quality acidic soils, characterised by open, low growing woody vegetation, often dominated by plants of the Ericaceae. There are some clear differences between heath and moorland...

.

Cultivation

This variety is little known in cultivation. It is suggested that cultivation requirements would be similar to the better-known B. sessilis var. sessilis, but that this variety would be better suited to cooler, wetter areas.

Conservation

On the Department of Environment and Conservation's Declared Rare and Priority Flora List, B. sessilis var. cordata is rated "Priority 4 - Rare", meaning that it has been adequately surveyed, and does not appear to be threatened, even though it is rare.

Further reading

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