Banksia sphaerocarpa
Encyclopedia
Banksia sphaerocarpa, commonly known as the Fox Banksia or Round-fruit Banksia, is a species of shrub
or tree in the plant genus Banksia
(family Proteaceae
). It is generally encountered as a 1–2 m (3–7 ft) high shrub, and is usually smaller in the north of its range. This species has narrow green leaves, and brownish, orange or yellow round flower spikes
which may be seen from January to July. It is widely distributed across the southwest of Western Australia
, growing exclusively in sandy soils. It is usually the dominant plant in scrubland or low woodland. It is pollinated by, and is a food source for, birds, mammals, and insects.
First described in 1810 by botanist Robert Brown
, B. sphaerocarpa has a complicated taxonomic
history, and several taxa
once classified as part of a broadly defined B. sphaerocarpa have since been named as species in their own right. At present, most authorities recognise five varieties; the largest variety, B. sphaerocarpa var. dolichostyla
(Ironcap Banksia), is sometimes given species rank as B. dolichostyla. B. sphaerocarpa is classified as Not Threatened under the Wildlife Conservation Act of Western Australia
, although two varieties have been placed on the Declared Rare and Priority Flora List—var. latifolia has been declared a Priority Two – Poorly Known taxon, and var. dolichostyla has been Declared Rare Flora. None of the varieties are commonly seen in cultivation.
, a swollen starchy root crown
from which the plant resprouts after bushfire. The new stems are finely hairy but become smooth with maturity. The leaves are stiff, narrow and linear, and measure 2.5–10 cm (1–4 in) in length, on a petiole 2–3 mm (0.1 in) long. Leaves of most varieties are 1–1.5 mm in width, and have a pointed tip, but var. latifolia has wider leaves, 2–2.5 cm (0.8–1 in), and a blunter tip. The foliage is green, or a more pale blue-grey in the case of caesia and dolichostyla.
The inflorescence
s are generally globular and measure 5 to 8 cm (2–3 in) in diameter, although larger forms, such as var. dolichostyla, are more oval in shape. Flowering from January to July, the blooms are yellow, orange or brownish in colour. They take five to eight weeks to develop from bud to the finish of flowering. Anthesis takes place over two weeks, as the individual flowers open in a wave across the inflorescence. Three weeks before the flowers open, the spikes develop a strong musky smell. The flowers produce unusually large quantities of nectar; indeed some flowers produce so much that it drips to the ground. The old flowers fade to brownish and grey hues and remain curled around the flower spike. Up to 60 follicles
develop on the globular spikes. The follicles are finely furred at first before becoming smooth and golden brown in colour, measuring 1.5–3 cm (0.6–1.2 in) long, 0.5–0.8 cm (0.2–0.3 in) high, and 1–2.5 cm (0.4–1 in) wide. The follicles are flat with pronounced 'shoulders', giving a rectangular appearance in cross section. Specimens of var. sphaerocarpa in the Whicher Range
, Jarrah Forest
and the vicinity of Nannup
have larger follicles. The seeds are wedge-shaped (cuneate), and measure 2.0–2.6 cm (0.8–1 in) in length, containing a smaller cuneate seed body measuring 1–1.4 cm (0.4–0.6 in) long by 0.5–1.3 cm (0.2–0.5 in) wide.
Northern specimens can be quite small shrubs and may be hard to distinguish from B. micrantha
, which has smaller inflorescences and large flattened follicles.
to King George Sound
. The specimen was collected from "A single plant observed between Princess Royal Harbour & Oyster Harbour on a heath", and is credited to English botanist Robert Brown
, though it is not possible to be certain on this point, as Brown incorporated the collections of junior expedition members into his herbarium without attribution. Neither Brown nor expedition horticulturist Peter Good
mentions the collection in his diary.
Brown published a formal description and name for the species in his 1810 On the Proteaceae of Jussieu. He did not designate a type specimen
(a specimen to be representative of the species) for the species, but the one specimen in his collection has since been formally declared the lectotype
for the species. He also did not state the etymology
of the specific epithet, but it is accepted that the name derives from the Ancient Greek
sphaera- ("round"), and carpos ("fruit"), in reference to the shape of its infructescences.
In Brown's arrangement of the genus
, B. sphaerocarpa was placed between B. pulchella
and B. nutans
in taxonomic sequence
; that is, an order that places related taxa next to each other. No subdivision of the genus was given, other than to separate a single distinctive species into a subgenus
of its own. Swiss botanist Carl Meissner
published a more detailed arrangement
in 1856, placing B. sphaerocarpa in section
Eubanksia
because its inflorescence is a spike rather than a domed head
, and in series
Abietinae
, whose members have inrolled leaf margins with no, or only very fine, serrations. Meissner also published a variety, B. sphaerocarpa var. glabrescens, based on specimens collected by James Drummond
; this is now considered a synonym of B. incana
.
George Bentham
's revision of Banksia
for his 1870 Flora Australiensis
overturned Meissner's series; instead, B. sphaerocarpa was placed in a new section, Oncostylis
, because of its hooked styles. Two varieties were recognised: Meissner's var. glabrescens was retained, and var. latifolia was newly described by Bentham. Bentham noted further variation amongst his specimens not accounted for by his varieties, stating "It is possible therefore that two species may be here confounded, but the specimens are insufficient for their distinction."
For many years following Bentham's arrangement, the circumscription of B. sphaerocarpa was widely recognised as unacceptably broad. William Blackall
informally published two varieties, var. pinifolia and var. violacea (properly Banksia violacea
) in his 1954 How to Know Western Australian Wildflowers
; and in 1966 the nurseryman Fred Lullfitz
predicted that there were as many as eight taxa within the species. Several of these were recognised in George's revision of the genus for 1981 "The genus Banksia L.f. (Proteaceae)
": B. micrantha
, B. grossa
, B. lanata
, B. scabrella
, B. telmatiaea
, B. leptophylla
and B. incana. George placed B. sphaerocarpa in subgenus Banksia
because of its flower spike, section Oncostylis because its styles are hooked, and the resurrected series Abietinae, which he constrained to contain only round-fruited species. He reduced variety latifolia to synonymy
with variety sphaerocarpa, but conceded the species needed further review. Alex George reported that he thought Banksia sphaerocarpas closest relatives to be Banksia micrantha
and B. grossa
.
George's arrangement remained current until 1996, when Kevin Thiele
and Pauline Ladiges published an arrangement
informed by a cladistic
analysis of morphological
characteristics. They retained George's subgenera and many of his series, but discarded his sections. Banksia ser. Abietinae was found to be very nearly monophyletic
, and so retained. It further resolved into four subclades, so Thiele and Ladiges split it into four subseries. Banksia sphaerocarpa appeared in the second of these, initially called the ' grossa clade' for its most basal
member. As with George's classification, B. grossa and B. micrantha emerged as close relatives of B. sphaerocarpa.
This clade became the basis for new subseries Sphaerocarpae
, which Thiele defined as containing those species with lignotubers, styles loosely curling around the infructescence (although this trait was reversed in micrantha), and "transversely aligned cells of the seed wing inner face". Other than the most basal B. grossa, these species also have shouldered follicles. Having found B. micrantha to be more closely related than B. sphaerocarpa var. dolichostyla to the other varieties of B. sphaerocarpa, they promoted var. dolichostyla to species rank as Banksia dolichostyla. Morphological support for this was given by the fact that the old styles of var. dolichostyla are quite different from those of other varieties, being stouter, and tending not to curl around the infructescence as the others do.
Questioning the emphasis on cladistics in Thiele and Ladiges' arrangement, George published a slightly modified version of his 1981 arrangement in his 1999 treatment of Banksia for the Flora of Australia
series of monographs. He added that he did not feel the characters of dolichostyla alone justified specific rank, beings essentially merely larger in all parts than, but otherwise essentially similar to, var. caesia. Therefore he retained it as a variety of B. sphaerocarpa. To date, George's 1999 arrangement remains the most recent comprehensive classification. The placement of B. sphaerocarpa in George's 1999 arrangement
may be summarised as follows:
A 2002 study by American botanists Austin Mast
and Tom Givnish yielded a surprise when molecular analysis mapped out dolichostyla as a sister taxon to its geographical neighbour B. violacea, in a clade with B. laricina and B. incana. B. micrantha and the other two varieties of B. sphaerocarpa form a separate clade nearby.
Early in 2007, Mast and Thiele initiated a rearrangement of Banksia by merging Dryandra
into it, and publishing B. subg. Spathulatae
for the taxa having spoon-shaped cotyledon
s. 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. sphaerocarpa is placed in B. subg. Spathulatae.
In 2008, George reinstated B. sphaerocarpa var. latifolia, and published the new variety B. sphaerocarpa var. pumilio.
in the north, south to the Whicher Range
, Nannup, Albany
and Jerramungup
, and eastwards to the vicinity of Hyden
. It is mainly found on sandy soils in flat or gently sloped areas in shrubland
, mallee
or open woodland.
. Banksia sphaerocarpa var. latifolia , though not afforded legislative protection, has been identified as a "Priority Two – Poorly Known" taxon, because so few populations are known.
bee species Hylaeus sanguinipictus. Botanist Stephen Hopper
found pollen of B. sphaerocarpa on New Holland Honeyeater
s (Phylidonyris novaehollandiae) and Honey Possum
s (Tarsipes rostratus) at Cheyne Beach in a field study published in 1980.
Knowledge of the breeding system of B. sphaerocarpa comes from a 2009 study of genetic structure
within and across fragmented
plant populations, which made a case study
of B. sphaerocarpa var. caesia populations in the vicinity of Dongolocking, where the landscape has been severely fragmented by land clearing. Very little self-pollination
was observed. Most mating was between plants in the same population, but inter-population mating accounted for 15–33% of seed, a "very significant contribution... to overall reproductive dynamics". This figure was lowest in the smallest populations, which also exhibited lower rates of germination, smaller plants, and less genetic diversity than larger populations. One possible interpretation of this is that interpopulation mating confers a fitness advantage. There was also evidence of fine-scale genetic structure, with plants tending to be more closely related to nearby plants than to more distant plants. The authors suggest that gene flow was probably always limited in these populations, even before they were fragmented.
Banksia sphaerocarpa is one of five closely related Banksia species that have highly unusual flower nectar. Whereas other Banksia species produce nectar that is clear and watery, the nectar of these species is pale yellow initially, but gradually becomes darker and thicker, changing to a thick, olive-green mucilage within one to two days of secretion, and eventually becoming "an almost black, gelatinous lump adhering to the base of the flowers". It was first noted by Byron Lamont in 1980; he attributed it to cyanobacteria that feed off the nectar sugar
s. Noting that many of these cyanobacteria had heterocyst
s, he speculated that they aid the plant by fixing atmospheric nitrogen
, which is then washed off the flower heads by rain, and absorbed by the proteoid root mat. This purported symbiosis
was investigated by Barrett and Lamont in 1985, but no evidence of nitrogen fixing was found. Further investigation by Markey and Lamont in 1996 suggested that the discolouration is not caused by cyanobacteria or other microorganisms in the nectar, but is rather "a chemical phenomenon of plant origin". Their analyses indicated that the nectar had unusually high levels of sugar and free amino acid
s, but three of these species, including B. sphaerocarpa, have since been shown to have normal nectar sugar compositions.
Like most Western Australian Banksia species, B. sphaerocarpa is susceptible to dieback from the soil-borne water mould Phytophthora cinnamomi
. In one experiment, 43% of plants were dead within three months of inoculation, and the species was therefore rated as "moderately susceptible". In another experiment, 37% of plants were dead within three months, and 85% within a year; yet this study rated the species' susceptibility as "high". In the latter study, it took 35 to 40 days for the death rate to reach its maximum, and thereafter the death rate continued at that level throughout the year, only dipping slightly in the dry summer months.
have been very limited and results have been poor. Otherwise, they adapt well to gardens with good drainage, sandy soils and sunny aspects in drier and Mediterranean (winter moisture) climates, and are also frost tolerant. They are good bird-attracting plants, and flower when not much else is in flower. Seeds do not require any treatment prior to sowing
, and take 20 to 48 days to germinate.
Shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
or tree in the plant genus 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...
(family Proteaceae
Proteaceae
Proteaceae is a family of flowering plants distributed in the Southern Hemisphere. The family comprises about 80 genera with about 1600 species. Together with the Platanaceae and Nelumbonaceae they make up the order Proteales. Well known genera include Protea, Banksia, Embothrium, Grevillea,...
). It is generally encountered as a 1–2 m (3–7 ft) high shrub, and is usually smaller in the north of its range. This species has narrow green leaves, and brownish, orange or yellow round flower spikes
Raceme
A raceme is a type of inflorescence that is unbranched and indeterminate and bears pedicellate flowers — flowers having short floral stalks called pedicels — along the axis. In botany, axis means a shoot, in this case one bearing the flowers. In a raceme, the oldest flowers are borne...
which may be seen from January to July. It is widely distributed across the southwest 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...
, growing exclusively in sandy soils. It is usually the dominant plant in scrubland or low woodland. It is pollinated by, and is a food source for, birds, mammals, and insects.
First described in 1810 by botanist Robert Brown
Robert Brown (botanist)
Robert Brown was a Scottish botanist and palaeobotanist who made important contributions to botany largely through his pioneering use of the microscope...
, B. sphaerocarpa has a complicated taxonomic
Taxonomy
Taxonomy is the science of identifying and naming species, and arranging them into a classification. The field of taxonomy, sometimes referred to as "biological taxonomy", revolves around the description and use of taxonomic units, known as taxa...
history, and several taxa
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
once classified as part of a broadly defined B. sphaerocarpa have since been named as species in their own right. At present, most authorities recognise five varieties; the largest variety, B. sphaerocarpa var. dolichostyla
Banksia sphaerocarpa var. dolichostyla
Banksia sphaerocarpa var. dolichostyla, commonly known as Ironcap Banksia, is a plant which is either considered a variety of Banksia sphaerocarpa, or as a species in its own right. It is native to the Southwest Botanical Province of Western Australia...
(Ironcap Banksia), is sometimes given species rank as B. dolichostyla. B. sphaerocarpa is classified as Not Threatened under the Wildlife Conservation Act of Western Australia
Wildlife Conservation Act 1950
The Wildlife Conservation Act 1950 is an act of the Western Australian Parliament that provides the statute relating to conservation and legal protection of flora and fauna....
, although two varieties have been placed on the Declared Rare and Priority Flora List—var. latifolia has been declared a Priority Two – Poorly Known taxon, and var. dolichostyla has been Declared Rare Flora. None of the varieties are commonly seen in cultivation.
Description
Banksia sphaerocarpa is a variable species that differs in plant size, flower size and leaf size across its range. The variability is marked enough that five varieties are recognised. This species is generally a shrub 0.4–2 m (1–7 ft) tall. Plants are smaller in northern parts of the range, and grow larger in the southeast, with var. dolichostyla and rarely var. caesia reaching 4 m (13 ft) in height. All varieties bear a lignotuberLignotuber
A lignotuber is a starchy swelling of the root crown possessed by some plants as a protection against destruction of the plant stem by fire. The crown contains buds from which new stems may sprout, and a sufficient store of nutrients to support a period of growth in the absence of...
, a swollen starchy root crown
Root crown
A root crown is that part of a root system from which a stem arises. Since roots and stems have quite different vascular anatomies, major vascular changes take place at this point....
from which the plant resprouts after bushfire. The new stems are finely hairy but become smooth with maturity. The leaves are stiff, narrow and linear, and measure 2.5–10 cm (1–4 in) in length, on a petiole 2–3 mm (0.1 in) long. Leaves of most varieties are 1–1.5 mm in width, and have a pointed tip, but var. latifolia has wider leaves, 2–2.5 cm (0.8–1 in), and a blunter tip. The foliage is green, or a more pale blue-grey in the case of caesia and dolichostyla.
The inflorescence
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Strictly, it is the part of the shoot of seed plants where flowers are formed and which is accordingly modified...
s are generally globular and measure 5 to 8 cm (2–3 in) in diameter, although larger forms, such as var. dolichostyla, are more oval in shape. Flowering from January to July, the blooms are yellow, orange or brownish in colour. They take five to eight weeks to develop from bud to the finish of flowering. Anthesis takes place over two weeks, as the individual flowers open in a wave across the inflorescence. Three weeks before the flowers open, the spikes develop a strong musky smell. The flowers produce unusually large quantities of nectar; indeed some flowers produce so much that it drips to the ground. The old flowers fade to brownish and grey hues and remain curled around the flower spike. Up to 60 follicles
Follicle (fruit)
In botany, a follicle is a dry unilocular many-seeded fruit formed from one carpel and dehiscing by the ventral suture in order to release seeds, such as in larkspur, magnolia, banksia, peony and milkweed....
develop on the globular spikes. The follicles are finely furred at first before becoming smooth and golden brown in colour, measuring 1.5–3 cm (0.6–1.2 in) long, 0.5–0.8 cm (0.2–0.3 in) high, and 1–2.5 cm (0.4–1 in) wide. The follicles are flat with pronounced 'shoulders', giving a rectangular appearance in cross section. Specimens of var. sphaerocarpa in the Whicher Range
Whicher Range
Whicher Range is a range in the South West region of Western Australia The range as an average elevation of above sea level.Bounded by the Swan Coastal Plain to the West and the South, the Darling Scarp to the North and the Blackwood Plateau to the East, the range is located approximately South...
, Jarrah Forest
Jarrah Forest
Jarrah Forest is an Interim Biogeographic Regionalisation for Australia region in Western Australia.-Location and description:The ecoregion stands on the 300m high Yilgarn block inland plateau and includes wooded valleys such as those of Western Australia's Murray River and the Helena River near...
and the vicinity of Nannup
Nannup, Western Australia
Nannup is a town and shire in the South West region of Western Australia, approximately south of Perth on the Blackwood River at the crossroads of Vasse Highway and Brockman Highway, linking Nannup to most of the Lower South West's regional centres...
have larger follicles. The seeds are wedge-shaped (cuneate), and measure 2.0–2.6 cm (0.8–1 in) in length, containing a smaller cuneate seed body measuring 1–1.4 cm (0.4–0.6 in) long by 0.5–1.3 cm (0.2–0.5 in) wide.
Northern specimens can be quite small shrubs and may be hard to distinguish from B. micrantha
Banksia micrantha
Banksia micrantha is a species of shrub in the plant genus Banksia. A small spreading bush with pale yellow flower spikes, it occurs between Eneabba and Cervantes in South west Western Australia...
, which has smaller inflorescences and large flattened follicles.
Taxonomy
The earliest known botanical collection of B. sphaerocarpa occurred in December 1801, during the visit of HMS InvestigatorHMS Investigator
Nine ships of the Royal Navy have borne the name HMS Investigator. Another was planned, but renamed before being launched: was a 22-gun armed ship purchased in 1798 and taken into service as HMS Xenophon. She was renamed HMS Investigator in 1801 and used as a survey ship. Under the command of...
to King George Sound
King George Sound
King George Sound is the name of a sound on the south coast of Western Australia. Located at , it is the site of the city of Albany.The sound covers an area of and varies in depth from to ....
. The specimen was collected from "A single plant observed between Princess Royal Harbour & Oyster Harbour on a heath", and is credited to English botanist Robert Brown
Robert Brown (botanist)
Robert Brown was a Scottish botanist and palaeobotanist who made important contributions to botany largely through his pioneering use of the microscope...
, though it is not possible to be certain on this point, as Brown incorporated the collections of junior expedition members into his herbarium without attribution. Neither Brown nor expedition horticulturist Peter Good
Peter Good
Peter Good was the gardener assistant to botanist Robert Brown on the voyage of HMS Investigator under Matthew Flinders, during which the coast of Australia was charted, and various plants collected.-Biography:...
mentions the collection in his diary.
Brown published a formal description and name for the species in his 1810 On the Proteaceae of Jussieu. He did not designate a type specimen
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
(a specimen to be representative of the species) for the species, but the one specimen in his collection has since been formally declared the lectotype
Lectotype
In botanical nomenclature and zoological nomenclature, a lectotype is a kind of name-bearing type. When a species was originally described on the basis of a name-bearing type consisting of multiple specimens, one of those may be designated as the lectotype...
for the species. He also did not state the 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...
of the specific epithet, but it is accepted that the name derives from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
sphaera- ("round"), and carpos ("fruit"), in reference to the shape of its infructescences.
In Brown's arrangement of the genus
Brown's taxonomic arrangement of Banksia
Robert Brown's taxonomic arrangement of Banksia was published in his 1810 Prodromus Florae Novae Hollandiae et Insulae Van Diemen, and expanded in this 1830 supplement to that publication, Supplementum Primum Prodromi Florae Novae Hollandiae...
, B. sphaerocarpa was placed between B. pulchella
Banksia pulchella
The Teasel Banksia is a species of small shrub in the plant genus Banksia. It occurs on the south coast of Western Australia from Fitzgerald River National Park east to Israelite Bay....
and B. nutans
Banksia nutans
Banksia nutans, commonly known as Nodding Banksia, is a species of shrub native to the south coast of Western Australia in the genus Banksia...
in taxonomic sequence
Taxonomic sequence
Taxonomic sequence is a sequence followed in listing of taxa which aids ease of use and roughly reflects the evolutionary relationships among the taxa...
; that is, an order that places related taxa next to each other. No subdivision of the genus was given, other than to separate a single distinctive species into a subgenus
Subgenus
In biology, a subgenus is a taxonomic rank directly below genus.In zoology, a subgeneric name can be used independently or included in a species name, in parentheses, placed between the generic name and the specific epithet: e.g. the Tiger Cowry of the Indo-Pacific, Cypraea tigris Linnaeus, which...
of its own. Swiss botanist 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...
published a more detailed arrangement
Meissner's taxonomic arrangement of Banksia
Carl Meissner's taxonomic arrangement of Banksia was published in 1856, as part of his chapter on the Proteaceae in A. P. de Candolle's Prodromus systematis naturalis regni vegetabilis. It was the first attempt to provide an infrageneric classification for the genus, aside from Robert Brown's...
in 1856, placing B. sphaerocarpa in section
Section (botany)
In botany, a section is a taxonomic rank below the genus, but above the species. The subgenus, if present, is higher than the section, and the rank of series, if present, is below the section. Sections are typically used to help organise very large genera, which may have hundreds of species...
Eubanksia
Banksia sect. Eubanksia
Banksia sect. Eubanksia is an obsolete section of Banksia. There have been two circumscriptions, one of which is synonymous with the recently abandoned B. subg. Banksia sensu Alex George, the other having no modern equivalent....
because its inflorescence is a spike rather than a domed head
Head (botany)
The capitulum is considered the most derived form of inflorescence. Flower heads found outside Asteraceae show lesser degrees of specialization....
, and in series
Series (botany)
Series is a low-level taxonomic rank below that of section but above that of species.In botany, a series is a subdivision of a genus...
Abietinae
Banksia ser. Abietinae
Banksia ser. Abietinae is avalid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...
, whose members have inrolled leaf margins with no, or only very fine, serrations. Meissner also published a variety, B. sphaerocarpa var. glabrescens, based on specimens collected by James Drummond
James Drummond (botanist)
James Drummond was a botanist and naturalist who was an early settler in Western Australia.-Early life:...
; this is now considered a synonym of B. incana
Banksia incana
The Hoary Banksia is a species of small shrub in the plant genus Banksia. It occurs on sandplain heathland between Badgingarra and Eneabba in Western Australia, with outlying populations as far south as Perth. Seeds do not require any treatment, and take around 14 days to germinate....
.
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 :...
's revision of Banksia
Bentham's taxonomic arrangement of Banksia
George Bentham's taxonomic arrangement of Banksia was published in 1870, in Volume 5 of Bentham's Flora Australiensis. A substantial improvement on the previous arrangement, it would stand for over a century. It was eventually replaced by Alex George's 1981 arrangement, published in his classic...
for his 1870 Flora Australiensis
Flora Australiensis
Flora Australiensis: a description of the plants of the Australian Territory, more commonly referred to as Flora Australiensis, and also known by its standard abbreviation Fl. Austral., is a seven-volume flora of Australia published between 1863 and 1878 by George Bentham, with the assistance of...
overturned Meissner's series; instead, B. sphaerocarpa was placed in a new section, Oncostylis
Banksia sect. Oncostylis
Banksia sect. Oncostylis is one of four sections of subgenus Banksia subg. Banksia. It contains those Banksia species with hooked pistils. All of the species in Oncostylis also exhibit a top-down sequence of flower anthesis, except for Banksia nutans which is bottom-up.Banksia sect...
, because of its hooked styles. Two varieties were recognised: Meissner's var. glabrescens was retained, and var. latifolia was newly described by Bentham. Bentham noted further variation amongst his specimens not accounted for by his varieties, stating "It is possible therefore that two species may be here confounded, but the specimens are insufficient for their distinction."
For many years following Bentham's arrangement, the circumscription of B. sphaerocarpa was widely recognised as unacceptably broad. William Blackall
William Blackall
William E. Blackall was a Western Australia medical doctor who made a substantial contribution to that state's botany.Born in Folkestone, Kent, England, he emigrated to Perth in 1905. His occupation was in medicine, but he is now best known for his amateur botany...
informally published two varieties, var. pinifolia and var. violacea (properly Banksia violacea
Banksia violacea
Banksia violacea, commonly known as Violet Banksia, is a species of shrub or tree in the plant genus Banksia . It generally grows as a small shrub to 1.5 m high with fine narrow leaves, and is best known for its unusually coloured dark purple-violet inflorescences...
) in his 1954 How to Know Western Australian Wildflowers
How to know Western Australian wildflowers
How to know Western Australian wildflowers is a series of books that provide illustrated keys to the vascular flora of the southern half of Western Australia....
; and in 1966 the nurseryman Fred Lullfitz
Fred Lullfitz
Frederick Conrad James Lullfitz , known as Fred Lullfitz, was a Western Australian botanist and horticulturist.Born in Perth, Western Australia in 1914, he studied botany at the University of Western Australia...
predicted that there were as many as eight taxa within the species. Several of these were recognised in George's revision of the genus for 1981 "The genus Banksia L.f. (Proteaceae)
The genus Banksia L.f. (Proteaceae)
The genus Banksia L.f. is a 1981 monograph by Alex George on the taxonomy of the plant genus Banksia. Published by the Western Australian Herbarium as Nuytsia 3, it presented George's taxonomic arrangement of Banksia, the first major taxonomic revision of the genus since George Bentham published...
": B. micrantha
Banksia micrantha
Banksia micrantha is a species of shrub in the plant genus Banksia. A small spreading bush with pale yellow flower spikes, it occurs between Eneabba and Cervantes in South west Western Australia...
, B. grossa
Banksia grossa
Banksia grossa, commonly known as Coarse Banksia is a species of shrub in the plant family Proteaceae endemic to south west Western Australia. One of fourteen species of banksia with predominantly round or oval inflorescences of the series Abietinae, it was described in 1981 as a distinct species...
, B. lanata
Banksia lanata
The Coomallo Banksia is a species of shrub in the plant genus Banksia. It occurs within a range of less than 100 square kilometres between Eneabba and Mount Lesueur, Western Australia. It has roughly spherical inflorescences with flowers of cream to orange-brown colour. The leaves are linear and...
, B. scabrella
Banksia scabrella
Banksia scabrella, commonly known as the Burma Road Banksia, is a species of woody shrub in the genus Banksia. It is classified in the series Abietinae, a group of several species of shrubs with small round or oval inflorescences...
, B. telmatiaea
Banksia telmatiaea
Banksia telmatiaea, commonly known as Swamp Fox Banksia or rarely Marsh Banksia, is a shrub that grows in marshes and swamps along the lower west coast of Australia. It grows as an upright bush up to 2 m tall, with narrow leaves and a pale brown flower spike, which can produce profuse...
, B. leptophylla
Banksia leptophylla
The Slender-leaved Banksia is a species of shrub in the plant genus Banksia. It occurs along the west coast of Western Australia from Gingin to Kalbarri. Before Alex George's revision of 1981, it was labelled informally as B. sphaerocarpa var. pinifolia or var...
and B. incana. George placed B. sphaerocarpa in subgenus Banksia
Banksia subg. Banksia
Banksia subg. Banksia is a valid botanic name for a subgenus of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata . Within this constraint, however, there have been various circumscriptions.-Banksia verae:B. subg...
because of its flower spike, section Oncostylis because its styles are hooked, and the resurrected series Abietinae, which he constrained to contain only round-fruited species. He reduced variety latifolia to synonymy
Synonym (taxonomy)
In scientific nomenclature, a synonym is a scientific name that is or was used for a taxon of organisms that also goes by a different scientific name. For example, Linnaeus was the first to give a scientific name to the Norway spruce, which he called Pinus abies...
with variety sphaerocarpa, but conceded the species needed further review. Alex George reported that he thought Banksia sphaerocarpas closest relatives to be Banksia micrantha
Banksia micrantha
Banksia micrantha is a species of shrub in the plant genus Banksia. A small spreading bush with pale yellow flower spikes, it occurs between Eneabba and Cervantes in South west Western Australia...
and B. grossa
Banksia grossa
Banksia grossa, commonly known as Coarse Banksia is a species of shrub in the plant family Proteaceae endemic to south west Western Australia. One of fourteen species of banksia with predominantly round or oval inflorescences of the series Abietinae, it was described in 1981 as a distinct species...
.
George's arrangement remained current until 1996, when 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...
and Pauline Ladiges published an arrangement
Thiele and Ladiges' taxonomic arrangement of Banksia
Kevin Thiele and Pauline Ladiges' taxonomic arrangement of Banksia, published in 1996, was a novel taxonomic arrangement that was intended to align the taxonomy of Banksia more closely with the phylogeny that they had inferred from their cladistic analysis of the genus...
informed by a cladistic
Cladistics
Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...
analysis of morphological
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
characteristics. They retained George's subgenera and many of his series, but discarded his sections. Banksia ser. Abietinae was found to be very nearly monophyletic
Monophyly
In common cladistic usage, a monophyletic group is a taxon which forms a clade, meaning that it contains all the descendants of the possibly hypothetical closest common ancestor of the members of the group. The term is synonymous with the uncommon term holophyly...
, and so retained. It further resolved into four subclades, so Thiele and Ladiges split it into four subseries. Banksia sphaerocarpa appeared in the second of these, initially called the ' grossa clade' for its most basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
member. As with George's classification, B. grossa and B. micrantha emerged as close relatives of B. sphaerocarpa.
This clade became the basis for new subseries Sphaerocarpae
Banksia subser. Sphaerocarpae
Banksia subser. Sphaerocarpae is a valid botanic name for a subseries of Banksia. It was published by Kevin Thiele in 1996, but discarded by Alex George in 1999.-Cladistics:...
, which Thiele defined as containing those species with lignotubers, styles loosely curling around the infructescence (although this trait was reversed in micrantha), and "transversely aligned cells of the seed wing inner face". Other than the most basal B. grossa, these species also have shouldered follicles. Having found B. micrantha to be more closely related than B. sphaerocarpa var. dolichostyla to the other varieties of B. sphaerocarpa, they promoted var. dolichostyla to species rank as Banksia dolichostyla. Morphological support for this was given by the fact that the old styles of var. dolichostyla are quite different from those of other varieties, being stouter, and tending not to curl around the infructescence as the others do.
Questioning the emphasis on cladistics in Thiele and Ladiges' arrangement, George published a slightly modified version of his 1981 arrangement in his 1999 treatment of Banksia for the Flora of Australia
Flora of Australia (series)
The Flora of Australia is a 59 volume series describing the vascular plants, bryophytes and lichens present in Australia and its external territories...
series of monographs. He added that he did not feel the characters of dolichostyla alone justified specific rank, beings essentially merely larger in all parts than, but otherwise essentially similar to, var. caesia. Therefore he retained it as a variety of B. sphaerocarpa. To date, George's 1999 arrangement remains the most recent comprehensive classification. The placement of B. sphaerocarpa in George's 1999 arrangement
George's taxonomic arrangement of Banksia
Alex George's taxonomic arrangement of Banksia was the first modern-day arrangement for that genus. First published in 1981 in the classic monograph The genus Banksia L.f. , it superseded the arrangement of George Bentham, which had stood for over a hundred years. It was overturned in 1996 by Kevin...
may be summarised as follows:
- BanksiaBanksiaBanksia 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...
- B. subg. BanksiaBanksia subg. BanksiaBanksia subg. Banksia is a valid botanic name for a subgenus of Banksia. As an autonym, it necessarily contains the type species of Banksia, B. serrata . Within this constraint, however, there have been various circumscriptions.-Banksia verae:B. subg...
- B. sect. BanksiaBanksia sect. BanksiaBanksia sect. Banksia is one of four sections of Banksia subgenus Banksia. It contains those species of subgenus Banksia with straight or sometimes curved but not hooked styles. These species all have cylindrical inflorescences and usually exhibit a bottom-up sequence of flower anthesis...
(9 series, 50 species, 9 subspecies, 3 varieties) - B. sect. Coccinea (1 species)
- B. sect. OncostylisBanksia sect. OncostylisBanksia sect. Oncostylis is one of four sections of subgenus Banksia subg. Banksia. It contains those Banksia species with hooked pistils. All of the species in Oncostylis also exhibit a top-down sequence of flower anthesis, except for Banksia nutans which is bottom-up.Banksia sect...
- B. ser. SpicigeraeBanksia ser. SpicigeraeBanksia ser. Spicigerae is a taxonomic series in the genus Banksia. It consists of the seven species in section Oncostylis that have cylindrical inflorescences. These range in form from small shrubs to tall trees. The leaves grow in either an alternate or whorled pattern, with various shape forms...
(7 species, 2 subspecies, 4 varieties) - B. ser. Tricuspidae (1 species)
- B. ser. DryandroideaeBanksia ser. DryandroideaeBanksia ser. Dryandroideae is a valid botanic name for a taxonomic series in the plant genus Banksia. First published by Carl Meissner in 1856, the name has had two circumscriptions. As presently circumscribed it is monotypic, containing only B. dryandroides.-According to Meissner:B. ser...
(1 species) - B. ser. AbietinaeBanksia ser. AbietinaeBanksia ser. Abietinae is avalid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...
- B. sphaerocarpa
- B. sphaerocarpa var. dolichostylaBanksia sphaerocarpa var. dolichostylaBanksia sphaerocarpa var. dolichostyla, commonly known as Ironcap Banksia, is a plant which is either considered a variety of Banksia sphaerocarpa, or as a species in its own right. It is native to the Southwest Botanical Province of Western Australia...
- B. sphaerocarpa var. latifoliaBanksia sphaerocarpa var. latifoliaBanksia sphaerocarpa var. latifolia is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia, specifically the vicinity of the south coast between Denmark and the Porongorup Range....
- B. sphaerocarpa var. pumilioBanksia sphaerocarpa var. pumilioBanksia sphaerocarpa var. pumilio is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia, specifically from Tathra National Park south to Chittering Valley....
- B. sphaerocarpa var. sphaerocarpaBanksia sphaerocarpa var. sphaerocarpaBanksia sphaerocarpa var. sphaerocarpa is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia. As an autonym, it is defined as containing the type specimen of the species....
- B. sphaerocarpa var. caesiaBanksia sphaerocarpa var. caesiaBanksia sphaerocarpa var. caesia is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia....
- B. sphaerocarpa var. dolichostyla
- B. micranthaBanksia micranthaBanksia micrantha is a species of shrub in the plant genus Banksia. A small spreading bush with pale yellow flower spikes, it occurs between Eneabba and Cervantes in South west Western Australia...
- B. grossaBanksia grossaBanksia grossa, commonly known as Coarse Banksia is a species of shrub in the plant family Proteaceae endemic to south west Western Australia. One of fourteen species of banksia with predominantly round or oval inflorescences of the series Abietinae, it was described in 1981 as a distinct species...
- B. telmatiaeaBanksia telmatiaeaBanksia telmatiaea, commonly known as Swamp Fox Banksia or rarely Marsh Banksia, is a shrub that grows in marshes and swamps along the lower west coast of Australia. It grows as an upright bush up to 2 m tall, with narrow leaves and a pale brown flower spike, which can produce profuse...
- B. leptophyllaBanksia leptophyllaThe Slender-leaved Banksia is a species of shrub in the plant genus Banksia. It occurs along the west coast of Western Australia from Gingin to Kalbarri. Before Alex George's revision of 1981, it was labelled informally as B. sphaerocarpa var. pinifolia or var...
(2 varieties) - B. lanataBanksia lanataThe Coomallo Banksia is a species of shrub in the plant genus Banksia. It occurs within a range of less than 100 square kilometres between Eneabba and Mount Lesueur, Western Australia. It has roughly spherical inflorescences with flowers of cream to orange-brown colour. The leaves are linear and...
- B. scabrellaBanksia scabrellaBanksia scabrella, commonly known as the Burma Road Banksia, is a species of woody shrub in the genus Banksia. It is classified in the series Abietinae, a group of several species of shrubs with small round or oval inflorescences...
- B. violaceaBanksia violaceaBanksia violacea, commonly known as Violet Banksia, is a species of shrub or tree in the plant genus Banksia . It generally grows as a small shrub to 1.5 m high with fine narrow leaves, and is best known for its unusually coloured dark purple-violet inflorescences...
- B. incanaBanksia incanaThe Hoary Banksia is a species of small shrub in the plant genus Banksia. It occurs on sandplain heathland between Badgingarra and Eneabba in Western Australia, with outlying populations as far south as Perth. Seeds do not require any treatment, and take around 14 days to germinate....
- B. laricinaBanksia laricinaThe Rose-Fruited Banksia is a species of shrub in the plant genus Banksia endemic to southwestern Western Australia. It derives its specific Latin name from larix or larch, which its foliage is said to resemble. The common name comes from the striking fruits which resemble wooden roses...
- B. pulchellaBanksia pulchellaThe Teasel Banksia is a species of small shrub in the plant genus Banksia. It occurs on the south coast of Western Australia from Fitzgerald River National Park east to Israelite Bay....
- B. meisneriBanksia meisneriThe Meisner's Banksia is a species of small shrub in the plant genus Banksia. It occurs in a number of isolated populations throughout southwest Western Australia. Seeds do not require any treatment, and take 28 to 39 days to germinate.-External links:...
(2 subspecies) - B. nutansBanksia nutansBanksia nutans, commonly known as Nodding Banksia, is a species of shrub native to the south coast of Western Australia in the genus Banksia...
(2 varieties)
- B. sphaerocarpa
- B. ser. Spicigerae
- B. sect. Banksia
- B. subg. IsostylisBanksia subg. IsostylisBanksia 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...
(3 species)
- B. subg. Banksia
A 2002 study by American botanists 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 Tom Givnish yielded a surprise when molecular analysis mapped out dolichostyla as a sister taxon to its geographical neighbour B. violacea, in a clade with B. laricina and B. incana. B. micrantha and the other two varieties of B. sphaerocarpa form a separate clade nearby.
Early in 2007, Mast and Thiele initiated a rearrangement of Banksia by merging 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 it, and publishing B. subg. Spathulatae
Banksia subg. Spathulatae
Banksia subg. Spathulatae is a valid botanic name for a subgenus of Banksia. It was published in 2007 by Austin Mast and Kevin Thiele, and defined as containing all those Banksia species having spathulate cotyledons...
for the taxa having spoon-shaped cotyledon
Cotyledon
A cotyledon , is a significant part of the embryo within the seed of a plant. Upon germination, the cotyledon may become the embryonic first leaves of a seedling. The number of cotyledons present is one characteristic used by botanists to classify the flowering plants...
s. 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. sphaerocarpa is placed in B. subg. Spathulatae.
In 2008, George reinstated B. sphaerocarpa var. latifolia, and published the new variety B. sphaerocarpa var. pumilio.
Varieties
Banksia sphaerocarpa is a widely distributed Western Australian species with four (or five if one includes var. dolichostyla) varieties:- B. sphaerocarpa var. caesiaBanksia sphaerocarpa var. caesiaBanksia sphaerocarpa var. caesia is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia....
, first described by Alex George in his 1981 revision of the genus, grows larger than most other varieties, reaching 2 m (7 ft), or occasionally 4 m (13 ft), in height. It has yellow blooms and bluish grey foliage and is found in the central and southern Wheatbelt between the towns of PiawaningPiawaning, Western AustraliaThe townsite of Piawaning is located in the northern agricultural region, 160 km north-east of Perth and 28 km north-east of New Norcia. At the 2006 census, Piawaning had a population of 309....
, KojonupKojonup, Western AustraliaKojonup is a town located 256 km south-east of Perth, Western Australia along Albany Highway.The name Kojonup is believed to refer to the "Kodja" or stone axe made by Indigenous Australians from the local stone....
, NewdegateNewdegate, Western AustraliaNewdegate is a townsite in the great southern agricultural region, 399 km south-east of Perth and 52 km east of Lake Grace in Western Australia. The townsite was gazetted in 1925 and honours Sir Francis Newdegate, the Governor of Western Australia from 1920 to 1924...
and CorriginCorrigin, Western AustraliaCorrigin is a town located in the central Wheatbelt region of Western Australia, east-southeast of the state capital, Perth, Western Australia, along State Route 40...
.
- B. sphaerocarpa var. dolichostylaBanksia sphaerocarpa var. dolichostylaBanksia sphaerocarpa var. dolichostyla, commonly known as Ironcap Banksia, is a plant which is either considered a variety of Banksia sphaerocarpa, or as a species in its own right. It is native to the Southwest Botanical Province of Western Australia...
(Ironcap Banksia) was first described by Alex George in his 1981 revision of the genus. It is the largest of the varieties, encountered as a large shrub or small tree to 4 m (13 ft) high. It is larger in all parts than the other varieties, and has been considered a separate species. It is restricted to a small area from South Ironcap, east of Hyden, south to Mt Holland in the eastern Wheatbelt.
- B. sphaerocarpa var. latifoliaBanksia sphaerocarpa var. latifoliaBanksia sphaerocarpa var. latifolia is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia, specifically the vicinity of the south coast between Denmark and the Porongorup Range....
was originally described in a manuscript by Mueller and published by Bentham in 1870. It grows as a small rounded shrub to 50 cm (1.5 ft) in height, and is restricted to the vicinity of the south coast between DenmarkDenmark, Western AustraliaDenmark 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:...
and the Porongorup RangePorongurup National ParkPorongurup National Park is a national park in the Great Southern region of Western Australia , 360 km southeast of Perth and 40 km from Albany....
, where it is found in low, open forest of Eucalyptus marginata and E. calophylla.
- B. sphaerocarpa var. sphaerocarpaBanksia sphaerocarpa var. sphaerocarpaBanksia sphaerocarpa var. sphaerocarpa is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia. As an autonym, it is defined as containing the type specimen of the species....
is widely distributed from the Darling Plateau east of Perth to the Whicher RangeWhicher RangeWhicher Range is a range in the South West region of Western Australia The range as an average elevation of above sea level.Bounded by the Swan Coastal Plain to the West and the South, the Darling Scarp to the North and the Blackwood Plateau to the East, the range is located approximately South...
in the southwest, and southeast to the Stirling RangeStirling RangeThe Stirling Range or Koikyennuruff is a range of mountains and hills in the Great Southern region of Western Australia, 337 km south-east of Perth. It is located at approximately and is over 60 km wide from west to east, stretching from the highway between Mount Barker and Cranbrook...
. Populations north of Perth once referable to it are now classified as var. pumilio.
- B. sphaerocarpa var. pumilioBanksia sphaerocarpa var. pumilioBanksia sphaerocarpa var. pumilio is a variety of Banksia sphaerocarpa. It is native to the Southwest Botanical Province of Western Australia, specifically from Tathra National Park south to Chittering Valley....
, first described by Alex George in 2008, is a small shrub less than a metre high. It is found from Tathra National ParkTathra National ParkTathra National Park is a national park in Western Australia , located north of Perth between the towns of Eneabba and Carnamah on Winchester-Eneabba Road...
east of Eneabba south to the Chittering valley. Its subspecific name is derived from the LatinLatinLatin 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...
pumilio "small", relating to the flowers.
Distribution and habitat
Banksia sphaerocarpa is distributed widely across southwestern Western Australia—from EneabbaEneabba, Western Australia
Eneabba is a town on the Brand Highway located 278 km north of Perth, Western Australia.The area is famous for its spectacular display of wildflowers in the spring. It is also home to the Iluka Resources mineral sands facility....
in the north, south to the Whicher Range
Whicher Range
Whicher Range is a range in the South West region of Western Australia The range as an average elevation of above sea level.Bounded by the Swan Coastal Plain to the West and the South, the Darling Scarp to the North and the Blackwood Plateau to the East, the range is located approximately South...
, Nannup, Albany
Albany, Western Australia
Albany is a port city in the Great Southern region of Western Australia, some 418 km SE of Perth, the state capital. As of 2009, Albany's population was estimated at 33,600, making it the 6th-largest city in the state....
and Jerramungup
Jerramungup, Western Australia
Jerramungup is a Western Australian town located in the Great Southern agricultural region, southeast of Perth just west of the Gairdner River. The town of Jerramungup was established in 1953 as a war service settlement area...
, and eastwards to the vicinity of Hyden
Hyden, Western Australia
The town of Hyden is located 339 km east of Perth, Western Australia in the Shire of Kondinin. Hyden is home to Wave Rock and Mulka's Cave, both popular local tourist attractions....
. It is mainly found on sandy soils in flat or gently sloped areas in shrubland
Shrubland
Shrubland, scrubland, scrub or brush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity...
, mallee
Mallee Woodlands and Shrublands
Mallee Woodlands and Shrublands is a Major Vegetation Group which occurs in semi-arid areas of southern Australia. The vegetation is dominated by mallee eucalypts which are rarely over 6 metres high...
or open woodland.
Conservation
As a species, B. sphaerocarpa is not considered to be under threat, but two of the five varieties, have been placed on the Declared Rare and Priority Flora List. B sphaerocarpa var. dolichostyla has been gazetted as "Declared Rare Flora – Extant" under the Wildlife Conservation Act 1950Wildlife Conservation Act 1950
The Wildlife Conservation Act 1950 is an act of the Western Australian Parliament that provides the statute relating to conservation and legal protection of flora and fauna....
. Banksia sphaerocarpa var. latifolia , though not afforded legislative protection, has been identified as a "Priority Two – Poorly Known" taxon, because so few populations are known.
Ecology
Various animals, including mammals, birds, and insects such as bees, wasps, ants and beetles, have been recorded visiting Banksia sphaerocarpa inflorescences, including the colletidColletidae
Colletidae is a family of bees, and are often referred to collectively as plasterer bees or polyester bees, due to the method of smoothing the walls of their nest cells with secretions applied with their mouthparts; these secretions dry into a cellophane-like lining...
bee species Hylaeus sanguinipictus. Botanist Stephen Hopper
Stephen Hopper
Stephen Donald Hopper is a Western Australian botanist, specialising in conservation biology and vascular plants. He has written eight books, and has over 200 publications to his name. He was Director of Kings Park in Perth for seven years, and CEO of the Botanic Gardens and Parks Authority for five...
found pollen of B. sphaerocarpa on New Holland Honeyeater
New Holland Honeyeater
The New Holland Honeyeater is a honeyeater species found throughout southern Australia. It was among the first birds to be scientifically described in Australia, and was initially named Certhia novaehollandiae...
s (Phylidonyris novaehollandiae) and Honey Possum
Honey Possum
The honey possum or tait, its Native Australian name or noolbenger is a tiny Australian marsupial weighing just seven to eleven grams for the male, and eight to sixteen grams for the female—about half the weight of a mouse. Their physical size ranges from a body length of between 6.5 –...
s (Tarsipes rostratus) at Cheyne Beach in a field study published in 1980.
Knowledge of the breeding system of B. sphaerocarpa comes from a 2009 study of genetic structure
Genetic structure
Genetic structure refers to any pattern in the genetic makeup of individuals within a population.In the absence of genetic structure, one can infer little to nothing about the genetic makeup of an individual by studying other members of the population...
within and across fragmented
Habitat fragmentation
Habitat fragmentation as the name implies, describes the emergence of discontinuities in an organism's preferred environment , causing population fragmentation...
plant populations, which made a case study
Case study
A case study is an intensive analysis of an individual unit stressing developmental factors in relation to context. The case study is common in social sciences and life sciences. Case studies may be descriptive or explanatory. The latter type is used to explore causation in order to find...
of B. sphaerocarpa var. caesia populations in the vicinity of Dongolocking, where the landscape has been severely fragmented by land clearing. Very little self-pollination
Self-pollination
Self-pollination is a form of pollination that can occur when a flower has both stamen and a carpel in which the cultivar or species is self fertile and the stamens and the sticky stigma of the carpel contact each other in order to accomplish pollination...
was observed. Most mating was between plants in the same population, but inter-population mating accounted for 15–33% of seed, a "very significant contribution... to overall reproductive dynamics". This figure was lowest in the smallest populations, which also exhibited lower rates of germination, smaller plants, and less genetic diversity than larger populations. One possible interpretation of this is that interpopulation mating confers a fitness advantage. There was also evidence of fine-scale genetic structure, with plants tending to be more closely related to nearby plants than to more distant plants. The authors suggest that gene flow was probably always limited in these populations, even before they were fragmented.
Banksia sphaerocarpa is one of five closely related Banksia species that have highly unusual flower nectar. Whereas other Banksia species produce nectar that is clear and watery, the nectar of these species is pale yellow initially, but gradually becomes darker and thicker, changing to a thick, olive-green mucilage within one to two days of secretion, and eventually becoming "an almost black, gelatinous lump adhering to the base of the flowers". It was first noted by Byron Lamont in 1980; he attributed it to cyanobacteria that feed off the nectar sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...
s. Noting that many of these cyanobacteria had heterocyst
Heterocyst
Heterocysts are specialized nitrogen-fixing cells formed by some filamentous cyanobacteria, such as Nostoc punctiforme, Cylindrospermum stagnale and Anabaena sphaerica, during nitrogen starvation. They fix nitrogen from dinitrogen in the air using the enzyme nitrogenase, in order to provide the...
s, he speculated that they aid the plant by fixing atmospheric nitrogen
Nitrogen fixation
Nitrogen fixation is the natural process, either biological or abiotic, by which nitrogen in the atmosphere is converted into ammonia . This process is essential for life because fixed nitrogen is required to biosynthesize the basic building blocks of life, e.g., nucleotides for DNA and RNA and...
, which is then washed off the flower heads by rain, and absorbed by the proteoid root mat. This purported symbiosis
Symbiosis
Symbiosis is close and often long-term interaction between different biological species. In 1877 Bennett used the word symbiosis to describe the mutualistic relationship in lichens...
was investigated by Barrett and Lamont in 1985, but no evidence of nitrogen fixing was found. Further investigation by Markey and Lamont in 1996 suggested that the discolouration is not caused by cyanobacteria or other microorganisms in the nectar, but is rather "a chemical phenomenon of plant origin". Their analyses indicated that the nectar had unusually high levels of sugar and free amino acid
Amino acid
Amino acids are molecules containing an amine group, a carboxylic acid group and a side-chain that varies between different amino acids. The key elements of an amino acid are carbon, hydrogen, oxygen, and nitrogen...
s, but three of these species, including B. sphaerocarpa, have since been shown to have normal nectar sugar compositions.
Like most Western Australian Banksia species, B. sphaerocarpa is susceptible to dieback from the soil-borne water mould Phytophthora cinnamomi
Phytophthora cinnamomi
Phytophthora cinnamomi is a soil-borne water mould that produces an infection which causes a condition in plants called root rot or dieback. The plant pathogen is one of the world's most invasive species and is present in over 70 countries from around the world.- Life cycle and effects on plants :P...
. In one experiment, 43% of plants were dead within three months of inoculation, and the species was therefore rated as "moderately susceptible". In another experiment, 37% of plants were dead within three months, and 85% within a year; yet this study rated the species' susceptibility as "high". In the latter study, it took 35 to 40 days for the death rate to reach its maximum, and thereafter the death rate continued at that level throughout the year, only dipping slightly in the dry summer months.
Cultivation
None of the varieties of Banksia sphaerocarpa are commonly seen in cultivation. They are difficult to grow in the wetter conditions of Australia's east coast. Trials with graftingGrafting
Grafting is a horticultural technique whereby tissues from one plant are inserted into those of another so that the two sets of vascular tissues may join together. This vascular joining is called inosculation...
have been very limited and results have been poor. Otherwise, they adapt well to gardens with good drainage, sandy soils and sunny aspects in drier and Mediterranean (winter moisture) climates, and are also frost tolerant. They are good bird-attracting plants, and flower when not much else is in flower. Seeds do not require any treatment prior to sowing
Sowing
Sowing is the process of planting seeds.-Plants which are usually sown:Among the major field crops, oats, wheat, and rye are sowed, grasses and legumes are seeded, and maize and soybeans are planted...
, and take 20 to 48 days to germinate.