Banksia kingii
Encyclopedia
Banksia kingii is an extinct
species of tree or shrub in the plant
genus
Banksia
. It is known only from fossil
leaves and fruiting "cones" found in Late
Pleistocene
sediment
at Melaleuca Inlet in western Tasmania
. These were discovered by Deny King
in the workings of his tin
mine
. The leaves and fruiting cones were discovered at different locations, and since the sediment had been removed during mining, the stratigraphy
of the fossils is unknown. The sediment from which they were recovered was alluvial
, consisting of large, well-rounded fragments of quartz
and schist
.
The fossil leaves are about 12 centimetres long and one centimetre wide and very thick and robust. They clearly belong to genus Banksia, section Banksia
, series Salicinae
, but not to any of the extant species in that series. The leaves of B. plagiocarpa
(Dallachy's Banksia) are similar in form, shape and robustness, but differ strongly in structure. Leaves of B. saxicola
(Grampians Banksia) are structurally the most similar to B. kingii, but have a different shape. There also appear to be some affinities with B. marginata
(Silver Banksia) and B. canei
(Mountain Banksia), but insufficient to warrant the fossil's ascription to those species. The fossils are therefore considered representative of a new species, B. kingii.
The fossil fruiting structures are cylindrical, about 6 centimetres high and 4½ centimetres wide. The structure had lost its old flower parts. It appears to be most closely related to B. saxicola and B. canei, with some similarities to B. marginata. The taxonomic situation therefore appears highly similar for both leaves and fruiting structures, and so the fruiting structures are ascribed to B. kingii despite the absence of any direct connection to the fossil leaves.
The species is believed to represent an extinct lineage. It is possible that it is an ancestor of B. marginata, although B. marginata must have speciated well before the extinction of B. kingii, given how widely it is now distributed. Extinction of B. kingii probably occurred in the late Quaternary
, and may have been caused by the climatic and physical disruption of glaciation, or by increased fire frequency due to human activity.
A formal description of B. kingii was published in 1991 by Gregory J. Jordan and Robert S. Hill, who named the species in honour of the discoverer, Deny King. Hence the species' full name is "Banksia kingii Jordan & Hill". The holotype
and a number of other specimens are stored in the Department of Plant Science at the University of Tasmania
.
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...
species of tree or shrub in the plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
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...
. It is known only from fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
leaves and fruiting "cones" found in Late
Late Pleistocene
The Late Pleistocene is a stage of the Pleistocene Epoch. The beginning of the stage is defined by the base of the Eemian interglacial phase before the final glacial episode of the Pleistocene 126,000 ± 5,000 years ago. The end of the stage is defined exactly at 10,000 Carbon-14 years BP...
Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
at Melaleuca Inlet in western Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
. These were discovered by Deny King
Deny King
Charles Denison Deny King AM was an Australian naturalist, ornithologist, environmentalist, painter and miner. He spent fifty five years living in Melaleuca in the remote South West Wilderness of Tasmania where he discovered the extinct shrub, Banksia kingii.King was a tin miner by profession and...
in the workings of his tin
Tin
Tin is a chemical element with the symbol Sn and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows chemical similarity to both neighboring group 14 elements, germanium and lead and has two possible oxidation states, +2 and the slightly more stable +4...
mine
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
. The leaves and fruiting cones were discovered at different locations, and since the sediment had been removed during mining, the stratigraphy
Stratigraphy
Stratigraphy, a branch of geology, studies rock layers and layering . It is primarily used in the study of sedimentary and layered volcanic rocks....
of the fossils is unknown. The sediment from which they were recovered was alluvial
Alluvium
Alluvium is loose, unconsolidated soil or sediments, eroded, deposited, and reshaped by water in some form in a non-marine setting. Alluvium is typically made up of a variety of materials, including fine particles of silt and clay and larger particles of sand and gravel...
, consisting of large, well-rounded fragments of quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
and schist
Schist
The schists constitute a group of medium-grade metamorphic rocks, chiefly notable for the preponderance of lamellar minerals such as micas, chlorite, talc, hornblende, graphite, and others. Quartz often occurs in drawn-out grains to such an extent that a particular form called quartz schist is...
.
The fossil leaves are about 12 centimetres long and one centimetre wide and very thick and robust. They clearly belong to genus Banksia, section Banksia
Banksia sect. Banksia
Banksia 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...
, series Salicinae
Banksia ser. Salicinae
Banksia ser. Salicinae is a valid botanic name for a series of Banksia. First published by Carl Meissner in 1856, the name has had three circumscriptions.-According to Meissner:...
, but not to any of the extant species in that series. The leaves of B. plagiocarpa
Banksia plagiocarpa
Banksia plagiocarpa, commonly known as the Dallachy's banksia or blue banksia, is a species of shrub or tree in the plant genus Banksia. It occurs only on Hinchinbrook Island, Queensland and the immediately adjacent mainland....
(Dallachy's Banksia) are similar in form, shape and robustness, but differ strongly in structure. Leaves of B. saxicola
Banksia saxicola
Banksia saxicola, commonly known as the Grampians Banksia is a species of tree or shrub in the plant genus Banksia. It occurs in Victoria in two distinct populations, one in The Grampians and the other on Wilsons Promontory....
(Grampians Banksia) are structurally the most similar to B. kingii, but have a different shape. There also appear to be some affinities with B. marginata
Banksia marginata
Banksia marginata, commonly known as the Silver Banksia, is a species of tree or woody shrub in the plant genus Banksia found throughout much of southeastern Australia. It ranges from the Eyre Peninsula in South Australia, to north of Armidale, New South Wales, and across Tasmania and the islands...
(Silver Banksia) and B. canei
Banksia canei
The mountain banksia is a species of shrub in the plant genus Banksia. It occurs in subalpine areas of the Great Dividing Range between Melbourne and Canberra in southeastern Australia...
(Mountain Banksia), but insufficient to warrant the fossil's ascription to those species. The fossils are therefore considered representative of a new species, B. kingii.
The fossil fruiting structures are cylindrical, about 6 centimetres high and 4½ centimetres wide. The structure had lost its old flower parts. It appears to be most closely related to B. saxicola and B. canei, with some similarities to B. marginata. The taxonomic situation therefore appears highly similar for both leaves and fruiting structures, and so the fruiting structures are ascribed to B. kingii despite the absence of any direct connection to the fossil leaves.
The species is believed to represent an extinct lineage. It is possible that it is an ancestor of B. marginata, although B. marginata must have speciated well before the extinction of B. kingii, given how widely it is now distributed. Extinction of B. kingii probably occurred in the late Quaternary
Quaternary
The Quaternary Period is the most recent of the three periods of the Cenozoic Era in the geologic time scale of the ICS. It follows the Neogene Period, spanning 2.588 ± 0.005 million years ago to the present...
, and may have been caused by the climatic and physical disruption of glaciation, or by increased fire frequency due to human activity.
A formal description of B. kingii was published in 1991 by Gregory J. Jordan and Robert S. Hill, who named the species in honour of the discoverer, Deny King. Hence the species' full name is "Banksia kingii Jordan & Hill". The holotype
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...
and a number of other specimens are stored in the Department of Plant Science at the University of Tasmania
University of Tasmania
The University of Tasmania is a medium-sized public Australian university based in Tasmania, Australia. Officially founded on 1 January 1890, it was the fourth university to be established in nineteenth-century Australia...
.