Alexgeorgea
Encyclopedia
Alexgeorgea is a genus of three plant species found in Western Australia
belonging to the family Restionaceae
named in honour of the botanist Alex George
in 1976. The flowers of the female and large nut-like fruit are completely underground except for the stigmas
, which extend out of the ground as 3 purple or red threads.
on 2 September 1974 when he found a population of A. subterranea on the Cockleshell Gully road north of Jurien Bay
in Western Australia
. At first, Carlquist, an American botanist and professor at Claremont Graduate University
doing field work in Western Australia, could only locate male plants of what he immediately identified as a restionaceous
species. In order to identify species in the Restionaceae, it is important to gather material of both male and female flowers, so Carlquist continued to search and only then noticed "purple thread-like structures emerging from the sand," which were the ephemeral styles of the mostly subterranean female flowers. In his original description of the new genus in a 1976 volume of the Australian Journal of Botany
, Carlquist notes his discovery may have not occurred if he had not seen the female flowers at anthesis
due to the short-lived nature of the thread-like styles.
Carlquist originally described two species in the genus, A. subterranea and A. arenicola (the species epithet arenicola means "a dweller on sand"). Ten year later in April 1986, Australian botanists Lawrence Alexander Sidney Johnson
and Barbara G. Briggs
, both of the Royal Botanic Gardens, Sydney
, published a short article in the journal Telopea
that recognized a species previously known as Restio nitens as a species better fitting the description of Alexgeorgea. Restio nitens was originally described by Christian Gottfried Daniel Nees von Esenbeck
in 1848 as having above ground dehiscent
fruits, unlike the below ground flowers and fruit of Alexgeorgea, though Carlquist had noted that R. nitens and his newly-described A. arenicola were otherwise identical. Johnson examined the herbarium specimens labeled as R. nitens and discovered that the alleged above ground fruits were actually malformations possibly resulting from smut fungus
. Both Johnson & Briggs and Carlquist independently published the new combination
, moving the species R. nitens to the genus Alexgeorgea as A. nitens. In Carlquist's proposal, he identified A. arenicola a synonym
of the older name A. nitens, which had priority. Johnson and Briggs published their description of A. nitens in the journal Telopea
on April 24, preceding Carlquist's publication in the journal Aliso
by only 5 days, thus making Carlquist's combination (A. nitens (Nees) Carlquist) an isonym of Johnson and Briggs's combination (A. nitens (Nees) L.A.S.Johnson & B.G.Briggs). The third species, A. ganopoda, was described by Johnson and Briggs in 1990.
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...
belonging to the family Restionaceae
Restionaceae
Restionaceae, also called restiads, is the botanical name for a family of rush-like flowering plants native to the Southern Hemisphere.- Description :...
named in honour of the botanist Alex George
Alex George
Alexander Segger George is a Western Australian botanist. He is the authority on the plant genera Banksia and Dryandra...
in 1976. The flowers of the female and large nut-like fruit are completely underground except for the stigmas
Stigma (botany)
The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma receives pollen at pollination and it is on the stigma that the pollen grain germinates. The stigma is adapted to catch and trap pollen with various hairs, flaps, or sculpturings...
, which extend out of the ground as 3 purple or red threads.
Botanical history
The genus Alexgeorgea was first discovered by Sherwin CarlquistSherwin Carlquist
Sherwin Carlquist is an American botanist and photographer. He received his undergraduate degree from the University of California, Berkeley in 1952 and a Ph.D. in botany in 1956, also at Berkeley. Carlquist did a postdoctoral study at Harvard University from 1955 to 1956. After his postdoctoral...
on 2 September 1974 when he found a population of A. subterranea on the Cockleshell Gully road north of Jurien Bay
Jurien Bay, Western Australia
-Demographics:At the ABS 2006 census, Jurien Bay had a population of 1,175, which represented over one-third of the total population of the Shire of Dandaragan...
in 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...
. At first, Carlquist, an American botanist and professor at Claremont Graduate University
Claremont Graduate University
Claremont Graduate University is a private, all-graduate research university located in Claremont, California, a city east of downtown Los Angeles...
doing field work in Western Australia, could only locate male plants of what he immediately identified as a restionaceous
Restionaceae
Restionaceae, also called restiads, is the botanical name for a family of rush-like flowering plants native to the Southern Hemisphere.- Description :...
species. In order to identify species in the Restionaceae, it is important to gather material of both male and female flowers, so Carlquist continued to search and only then noticed "purple thread-like structures emerging from the sand," which were the ephemeral styles of the mostly subterranean female flowers. In his original description of the new genus in a 1976 volume of the Australian Journal of Botany
Australian Journal of Botany
The Australian Journal of Botany is a peer-reviewed scientific journal that publishes original research, and sometimes review articles, on botanical topics, especially those related to Australian plants. It is broad in scope, covering all plant groups and a wide range of botanic disciplines. The...
, Carlquist notes his discovery may have not occurred if he had not seen the female flowers at anthesis
Anthesis
Anthesis is the period during which a flower is fully open and functional. It may also refer to the onset of that period.The onset of anthesis is spectacular in some species. In Banksia species, for example, anthesis involves the extension of the style far beyond the upper perianth parts...
due to the short-lived nature of the thread-like styles.
Carlquist originally described two species in the genus, A. subterranea and A. arenicola (the species epithet arenicola means "a dweller on sand"). Ten year later in April 1986, Australian botanists Lawrence Alexander Sidney Johnson
Lawrence Alexander Sidney Johnson
Lawrence Alexander Sidney Johnson, known as Lawrie Johnson, was an Australian taxonomic botanist. He worked at the Royal Botanic Gardens, Sydney, for the whole of his professional career, as a botanist , Director and Honorary Research Associate .Alone or in collaboration with colleagues, he...
and Barbara G. Briggs
Barbara G. Briggs
Barbara Gillian Briggs is one of the foremost Australian botanists. The IK lists 205 names of plants which have been published or co-published by her. She was one of the botanists in the Angiosperm Phylogeny Group, of the APG system....
, both of the Royal Botanic Gardens, Sydney
Royal Botanic Gardens, Sydney
The Royal Botanic Gardens in Sydney, Australia, are the most central of the three major botanical gardens open to the public in Sydney....
, published a short article in the journal Telopea
Telopea (journal)
Telopea is a peer-reviewed scientific journal that publishes original research on plant systematics, focusing on the flora of New South Wales but with broad content that covers Australia and the Asia-Pacific region. The journal was established in 1975 and is published biannually by the National...
that recognized a species previously known as Restio nitens as a species better fitting the description of Alexgeorgea. Restio nitens was originally described by Christian Gottfried Daniel Nees von Esenbeck
Christian Gottfried Daniel Nees von Esenbeck
Christian Gottfried Daniel Nees von Esenbeck was a prolific German botanist, physician, zoologist, and natural philosopher. He was a contemporary of Goethe and was born within the lifetime of Linnaeus. He described approximately 7,000 plant species...
in 1848 as having above ground dehiscent
Dehiscence (botany)
Dehiscence is the opening, at maturity, in a pre-defined way, of a plant structure, such as a fruit, anther, or sporangium, to release its contents. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent...
fruits, unlike the below ground flowers and fruit of Alexgeorgea, though Carlquist had noted that R. nitens and his newly-described A. arenicola were otherwise identical. Johnson examined the herbarium specimens labeled as R. nitens and discovered that the alleged above ground fruits were actually malformations possibly resulting from smut fungus
Smut (fungus)
The smuts are multicellular fungi, that are characterized by their large numbers of teliospores. The smuts get their name from a Germanic word for dirt because of their dark, thick-walled and dust-like teliospores. They are mostly Ustilaginomycetes and can cause plant disease...
. Both Johnson & Briggs and Carlquist independently published the new combination
Combinatio nova
Combinatio nova, abbreviated comb. nov., is Latin for "new combination".It is used in life sciences literature when a new name is introduced, e.g. when Calymmatobacterium granulomatis was renamed Klebsiella granulomatis it was referred to as Klebsiella granulomatis comb. nov. to denote it is a new...
, moving the species R. nitens to the genus Alexgeorgea as A. nitens. In Carlquist's proposal, he identified A. arenicola a synonym
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...
of the older name A. nitens, which had priority. Johnson and Briggs published their description of A. nitens in the journal Telopea
Telopea (journal)
Telopea is a peer-reviewed scientific journal that publishes original research on plant systematics, focusing on the flora of New South Wales but with broad content that covers Australia and the Asia-Pacific region. The journal was established in 1975 and is published biannually by the National...
on April 24, preceding Carlquist's publication in the journal Aliso
Aliso
Aliso is a peer-reviewed journal that publishes original research on plant taxonomy and evolutionary botany with a worldwide scope, but with a particular focus on the floristics of the Western United States. Aliso, first published in 1948, is the scientific journal of the Rancho Santa Ana Botanic...
by only 5 days, thus making Carlquist's combination (A. nitens (Nees) Carlquist) an isonym of Johnson and Briggs's combination (A. nitens (Nees) L.A.S.Johnson & B.G.Briggs). The third species, A. ganopoda, was described by Johnson and Briggs in 1990.
External links
- sherwincarlquist.com (Description of discovery)