''Dryandra'' subg. ''Hemiclidia'' is an obsolete plant taxon that encompassed material that is now included in '' Banksia''. Published at

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

rank as ''Hemiclidia'' by Robert Brown in 1830, it was set aside by George Bentham in 1870, but reinstated at subgenus rank by

Alex George Alexander or Alex George may refer to: *Alex George (botanist) (born 1939), Australian botanist * Alexander L. George (1920–2006), American political scientist * Alexander George (philosopher), American philosopher *Alex George (motorcyclist), Sc ...

in 1996. In 2007, all ''

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 extensiv ...

'' species were transferred into ''Banksia'' at series rank, and the infrageneric ''Dryandra'' taxa, including ''D.'' subg. ''Hemiclidia'', were set aside.

According to Brown

In 1810, Robert Brown published the genus ''Dryandra'' in his ''

On the Proteaceae of Jussieu ''On the natural order of plants called Proteaceae'', also published as "On the Proteaceae of Jussieu", was a paper written by Robert Brown on the taxonomy of the plant family Proteaceae. It was read to the Linnean Society of London in the first q ...

''. Thirteen species were published, including ''Dryandra falcata'' (now '' Banksia falcata''), but no infrageneric arrangement was proffered. Twenty years later, Brown published a further eleven species and the first infrageneric arrangement in his ''

Supplementum primum prodromi florae Novae Hollandiae ''Supplementum primum Prodromi florae Novae Hollandiae'' ("First supplement to the Prodromus of the flora of New Holland") is an 1830 supplement to Robert Brown's ''Prodromus florae Novae Hollandiae et Insulae Van Diemen''. It may be referred to ...

''. By this time, Brown had observed the tendency in ''D. falcata'' for one of the two

ovule In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the megasporangium), and the fe ...

s in each follicle to abort, thereafter developing into a winglike appendage to the seed separator. On this basis, he transferred the species into a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genus, which he named ''Hemiclidia'', from the Greek ''hemi'' ("half") and perhaps ''kleidos'' ("barrier", "means of closing"). ''Hemiclidia'' was retained in the 1856 arrangement of Carl Meissner, but discarded by George Bentham in his 1870 revision of the genus. Bentham correctly observed that the abortion of seeds occurs in other ''Dryandra'' species, and is a diagnostically unimportant character:

According to George

In 1996,

published a thorough revision of ''Dryandra'' in preparation of his monograph on that genus for the '' Flora of Australia'' series. He segregated ''D. falcata'' and the newly published ''D. glauca'' (now ''

Banksia glaucifolia ''Banksia glaucifolia'' is a species of shrub that is endemic to Western Australia. It has deeply serrated, wedge-shaped leaves with sharply pointed lobes, pale yellow flowers and follicles with hairy edges. Description ''Banksia glaucofolia'' ...

'') into a subgenus based on their unusual follicles, which are small, hairy and pliable. Needing a name for the subgenus, George noted that ''Hemiclidia'' was available, and had an appropriate

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

in ''D. falcata''. He therefore demoted ''Hemiclidia'' to subgenus rank as ''Dryandra'' subg. ''Hemiclidia'' (R.Br.) A.S.George. Its placement and circumscription in George's taxonomic arrangement of ''Dryandra'' may be summarised as follows: :Genus ''Dryandra'' (now ''Banksia'' ser. ''Dryandra'') ::Subgenus ''

'' (24 series, 91 species, 39 subspecies, 23 varieties) ::Subgenus ''Hemiclidia'' :::''D. falcata'' (now '' Banksia falcata'') :::''D. glauca'' (now ''

'') ::Subgenus '' Diplophragma'' (1 species) This arrangement remained current until 2007, when Austin Mast and Kevin Thiele transferred ''Dryandra'' into ''Banksia''. They were not yet ready, however, to tender an infrageneric arrangement encompassing ''Dryandra'', so as an interim measure they transferred ''Dryandra'' into ''Banksia'' at series rank. This minimised the nomenclatural disruption of the transfer, but also caused George's rich infrageneric arrangement to be set aside. Thus under the interim arrangements implemented by Mast and Thiele, ''D.'' subg. ''Hemiclidia'' has been set aside.

References

External links

* * {{DEFAULTSORT:Dryandra subg. Hemiclidia * subg. Hemiclidia Historically recognized angiosperm taxa Plant subgenera Taxa named by Robert Brown (botanist, born 1773)