Elegant banksia | |
---|---|
Cultivated specimen, Perth | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Order: | Proteales |
Family: | Proteaceae |
Genus: | Banksia |
Species: | B. elegans |
Binomial name | |
Banksia elegans | |
Synonyms [1] | |
Banksia elegans, commonly known as the elegant banksia, [2] is a species of woody shrub that is endemic to a relatively small area of Western Australia. Reaching 4 m (13 ft) high, it is a suckering shrub that rarely reproduces by seed. The round to oval yellow flower spikes appear in spring and summer. Swiss botanist Carl Meissner described Banksia elegans in 1856. It is most closely related to the three species in the subgenus Isostylis.
Banksia elegans grows as a many-stemmed spreading shrub to 4 m (13 ft) high. It commonly sends up suckers from either the roots or trunk. The trunk is up to 15 cm (5.9 in) in diameter and covered with grey tessellated bark. The new stems are covered with fine hair and become smooth with maturity. New growth mainly occurs in summer. The long thin pale blue-green leaves are 200–460 mm (7.9–18.1 in) long and 12–18 mm (0.47–0.71 in) wide. Their margins are prominently serrated in a saw-tooth pattern with triangular teeth and v-shaped sinuses. The yellow flower spikes, or inflorescences, are oval or spherical and reach 60–70 mm (2.4–2.8 in) in diameter. [2] [3] [4] [5]
A population with particularly large inflorescences existed near Walkaway at the species' northern limit, but was on land cleared for agriculture. [2] Each flower spike is composed of around 400 individual flowers. Over 90% of plants and 99% of flowerheads do not develop follicles and hence set no seed. [6]
Swiss botanist Carl Meissner described Banksia elegans in 1855, the material having been collected by James Drummond on his sixth collecting trip. [7] [8] He placed it in series Dryandroideae in his 1856 arrangement of the genus on account of its deeply lobed leaves. [9] As they were defined on leaf characters alone, all of Meissner's series were highly heterogeneous. [3] George Bentham published a thorough revision of Banksia in his landmark publication Flora Australiensis in 1870. In Bentham's arrangement, the number of recognised Banksia species was reduced from 60 to 46. Bentham defined four sections based on leaf, style and pollen-presenter characters. Banksia elegans was placed in section Orthostylis. [10]
In 1891, Otto Kuntze, in his Revisio Generum Plantarum , rejected the generic name Banksia L.f., on the grounds that the name Banksia had previously been published in 1776 as Banksia J.R.Forst & G.Forst, referring to the genus now known as Pimelea . Kuntze proposed Sirmuellera as an alternative, referring to this species as Sirmuellera elegans. [11] This application of the principle of priority was largely ignored by Kuntze's contemporaries, [12] and Banksia L.f. was formally conserved and Sirmuellera rejected in 1940. [13]
George was uncertain of its relationships, though noted that the follicles and seed are not unlike those of B. ilicifolia and B. cuneata , and that it clearly had a shortening of its woody axis in the flower spike. [3]
In 2002, a molecular study by Austin Mast showed B. elegans was basal to a group formed by the three members of the subgenus Isostylis, and that its next closest relative was B. attenuata [14]
In 2005, Mast, Eric Jones and Shawn Havery published the results of their cladistic analyses of DNA sequence data for Banksia. They inferred a phylogeny greatly different from the accepted taxonomic arrangement, including finding Banksia to be paraphyletic with respect to Dryandra . [15] A new taxonomic arrangement was not published at the time, but early in 2007 Mast and Thiele initiated a rearrangement by transferring Dryandra to Banksia, and publishing B. subg. Spathulatae for the species having spoon-shaped cotyledons; in this way they also redefined the autonym B. subg. Banksia. They foreshadowed publishing a full arrangement once DNA sampling of Dryandra was complete. In the meantime, if Mast and Thiele's nomenclatural changes are taken as an interim arrangement, then B. elegans is placed in B. subg. Banksia. [16]
Banksia elegans only occurs only over a 65 km2 (25 sq mi) area north and west of Eneabba, where it grows in small scattered populations consisting of fewer than 100 plants each. The populations are found between the vicinities of Mt Peron near Jurien Bay and Walkaway, on flat sandplains of less than 50 m (160 ft) in elevation. Stands are often found near winter-wet depressions. The surrounding vegetation is low shrubland or woodland. Associated species include Banksia attenuata, B. prionotes and B. menziesii. [2]
Banksia elegans sets an extremely low amount of seed, and appears to reproduce predominantly by suckering, despite prolific flowering and low rates of flower and follicle predation. Developing seeds are also often aborted. A population studied in one field study produced an average of only two seeds per plant in sixteen years. [6] Populations begin flowering three years after bushfire, and regenerate after fire from large underground lignotubers as well as sending up suckers. One field study found no seedlings at all post-bushfire, suggesting the shift to vegetative propagation maybe more marked than thought previously. [17]
An assessment of the potential impact of climate change on this species found that its range is unlikely to contract and may actually grow, depending on how effectively it migrates into newly habitable areas. [18]
This banksia is classified as "Priority Four" by the Government of Western Australia Department of Parks and Wildlife, [5] meaning that is rare or near threatened. [19]
Seeds do not require any treatment, and take 19 to 48 days to germinate. [20]
Banksia subg. Isostylis is a subgenus of Banksia. It contains three closely related species, all of which occur only in Southwest Western Australia. Members of subgenus Isostylis have dome-shaped flower heads that are superficially similar to those of B. ser. Dryandra, but structurally more like reduced versions of the "flower spikes" characteristic of most other Banksia taxa.
Banksia attenuata, commonly known as the candlestick banksia, slender banksia, or biara to the Noongar people, is a species of plant in the family Proteaceae. Commonly a tree, it reaches 10 m (33 ft) high, but it is often a shrub in drier areas 0.4 to 2 m high. It has long, narrow, serrated leaves and bright yellow inflorescences, or flower spikes, held above the foliage, which appear in spring and summer. The flower spikes age to grey and swell with the development of the woody follicles. The candlestick banksia is found across much of the southwest of Western Australia, from north of Kalbarri National Park down to Cape Leeuwin and across to Fitzgerald River National Park.
Banksia sceptrum, commonly known as the sceptre banksia, is a plant that grows in Western Australia near the central west coast from Geraldton north through Kalbarri to Hamelin Pool. It extends inland almost to Mullewa. First collected and grown by early settler James Drummond in Western Australia, it was described by Swiss botanist Carl Meissner in 1855.
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.
Banksia baueri, commonly known as the woolly banksia, is a species of shrub that is endemic to the southwest of Western Australia. It has serrated leaves and a distinctively large and hairy looking inflorescence with cream, yellow or brown flowers, and hairy fruit.
Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus.
Banksia dentata, commonly known as the tropical banksia, is a species of tree in the genus Banksia. It occurs across northern Australia, southern New Guinea and the Aru Islands. Growing as a gnarled tree to 7 m (23 ft) high, it has large green leaves up to 22 cm (8.7 in) long with dentate (toothed) margins. The cylindrical yellow inflorescences, up to 13 cm (5.1 in) high, appear over the cooler months, attracting various species of honeyeaters, sunbirds, the sugar glider and a variety of insects. Flowers fall off the ageing spikes, which swell and develop follicles containing up to two viable seeds each.
Banksia dryandroides, the dryandra-leaved banksia, is a species of small shrub in the plant genus Banksia. The Noongar peoples know the tree as manyat. It occurs in shrubland, woodland and kwongan on the south coast of Western Australia between Narrikup and Beaufort Inlet. The species is placed alone in series B. ser. Dryandroideae.
Banksia hookeriana, commonly known as Hooker's banksia, is a species of shrub of the genus Banksia in the family Proteaceae. It is native to the southwest of Western Australia and can reach up to 4 m (13 ft) high and 3 m (9.8 ft) wide. This species has long narrow serrated leaves and large, bright flower spikes, initially white before opening to a bright orange that appear over the cooler months. The flowers are pollinated by honeyeaters. The ageing flower spikes develop woody seed pods known as follicles. B. hookeriana is serotinous — large numbers of seeds are stored in the plant canopy for years until the plants are burnt by bushfire.
Banksia lemanniana, the yellow lantern banksia or Lemann's banksia, is a species of flowering plant in the family Proteaceae, native to Western Australia. It generally grows as an open woody shrub or small tree to 5 m (16 ft) high, with stiff serrated leaves and unusual hanging inflorescences. Flowering occurs over summer, the greenish buds developing into oval flower spikes before turning grey and developing the characteristic large woody follicles. It occurs within and just east of the Fitzgerald River National Park on the southern coast of the state. B. lemanniana is killed by bushfire and regenerates from seed.
Banksia lindleyana, commonly known as the porcupine banksia, is a species of woody shrub in the genus Banksia of the family Proteaceae. It generally grows as a small shrub to 1 m (3 ft) high with long narrow serrated leaves, and bright yellow oval or round inflorescences. Flowering occurs in late summer, after which time the flower spikes age and turn to brown and then grey, and develop up to 70 follicles. It occurs in the vicinity of Kalbarri, Western Australia. Found on sandy soils, the plant serves as a pollinator for a variety of bird and animal species.
Banksia media, the southern plains banksia or golden stalk banksia, is a species of flowering plant in the family Proteaceae. An evergreen shrub, it occurs on the south coast of Western Australia between Albany and Israelite Bay, where it is a common plant. A many-branched bush with wedge-shaped serrated leaves and large golden-yellow flower spikes, known as inflorescences, it grows up to 10 metres (30 ft) high.
Banksia nutans, commonly known as nodding banksia, is a species of shrub native to the south coast of Western Australia in the genus Banksia. Growing to a metre (3 ft) tall, it has pale blue-green fine-leaved foliage and unusual purple-brown inflorescences which hang upside down rather than grow upright like most other banksias.
Banksia praemorsa, commonly known as the cut-leaf banksia, is a species of shrub or tree in the plant genus Banksia. It occurs in a few isolated populations on the south coast of Western Australia between Albany and Cape Riche.
Banksia speciosa, commonly known as the showy banksia, is a species of large shrub or small tree in the family Proteaceae. It is found on the south coast of Western Australia between Hopetoun (33°57′ S) and the Great Australian Bight, growing on white or grey sand in shrubland. Reaching up to 8 m (26 ft) in height, it is a single-stemmed plant that has thin leaves with prominent triangular "teeth" along each margin, which are 20–45 cm (7.9–17.7 in) long and 2–4 cm (0.8–1.6 in) wide. The prominent cream-yellow flower spikes known as inflorescences appear throughout the year. As they age they develop up to 20 follicles each that store seeds until opened by fire. Though widely occurring, the species is highly sensitive to dieback and large populations of plants have succumbed to the disease.
Banksia victoriae, commonly known as Woolly Orange Banksia, is a species of large shrub or small tree in the plant genus Banksia. It occurs in Western Australia between Northampton, Western Australia and Kalbarri, with the occasional plant further north as far as Zuytdorp Nature Reserve.
Banksia fraseri is a species of shrub that is endemic to Western Australia. It has hairy stems, broadly linear pinnatisect leaves with between four and eighteen sharply-pointed lobes on each side, between eighty and one hundred pink to cream-coloured flowers and wege-shaped follicles.
Banksia acuminata is a rare prostrate shrub endemic to south-west Western Australia. It was published in 1848 as Dryandra preissii, but transferred into Banksia as B. acuminata in 2007.
Banksia spinulosa var. collina is a shrub that grows along the east coast of Australia, in Queensland and New South Wales. Commonly known as Hill Banksia or Golden Candlesticks, it is a taxonomic variety of B. spinulosa. It is a popular garden plant widely sold in nurseries.
Dryandra ser. Aphragma is an obsolete series within the former genus Dryandra. It was first published at sectional rank by Robert Brown in 1830, and was retained at that rank until 1999, when Alex George demoted it to a series. It was discarded in 2007 when Austin Mast and Kevin Thiele sank Dryandra into Banksia.