''Banksia'' ser. ''Crocinae'' is a

taxonomic Taxonomy is the practice and science of categorization or classification. A taxonomy (or taxonomical classification) is a scheme of classification, especially a hierarchical classification, in which things are organized into groups or types. ...

series in the

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 ...

'' Banksia''. The series was first published 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 1981, but discarded by Kevin Thiele and

Pauline Ladiges Pauline Yvonne Ladiges (born 1948) is a botanist whose contributions have been significant both in building the field of taxonomy, ecology and historical biogeography of Australian plants, particularly Eucalypts and flora, and in science educa ...

in 1996, and finally reinstated by George in 1999. Recent cladistic analyses suggest that it is

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

or nearly so.

Species

It consists of four closely related species, all of which are endemic to

Western Australia Western Australia (commonly abbreviated as WA) is a state of Australia occupying the western percent of the land area of Australia excluding external territories. It is bounded by the Indian Ocean to the north and west, the Southern Ocean to th ...

; namely

Systematics

George 1981

''B.'' ser. ''Banksia'' originated in the 1981 arrangement of George, published in his classic monograph ''

The genus Banksia L.f. (Proteaceae) "The genus ''Banksia'' L.f. (Proteaceae)" is a 1981 monograph by Alex George on the taxonomy of the plant genus ''Banksia''. Published by the Western Australian Herbarium as ''Nuytsia'' 3(3), it presented George's taxonomic arrangement of ''B ...

''. George grouped the four species into a series on the grounds that they are "remarkably similar especially in floral morphology", giving the series the name ''B.'' ser. ''Crocinae'' from the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''crocinus'' ("rich orange"), in reference to the bright orange

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. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

s. He also remarked that "the series is probably derived from the '' Orthostylis'', which can in hingsight be read as an admission of

paraphyly In taxonomy, a group is paraphyletic if it consists of the group's last common ancestor and most of its descendants, excluding a few monophyletic subgroups. The group is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

. The placement and circumscription of ''B.'' ser. ''Crocinae'' in George's 1981 arrangement may be summarised as follows: :''Banksia'' :: ''B.'' subg. ''Banksia'' ::: ''B.'' sect. ''Banksia'' :::: ''B.'' ser. ''Salicinae'' (9 species) :::: ''B.'' ser. ''Grandes'' (2 species) :::: ''B.'' ser. ''Quercinae'' (3 species) :::: ''B.'' ser. ''Orthostylis'' (4 species) ::::''B.'' ser. ''Crocinae'' :::::'' B. prionotes'' :::::'' B. victoriae'' :::::''B. hookerana'' (now spelled '' B. hookeriana'') :::::'' B. burdettii'' :::: ''B.'' ser. ''Cyrtostylis'' (12 species) :::: ''B.'' ser. ''Prostratae'' (6 species) :::: ''B.'' ser. ''Tetragonae'' (3 species) :::: ''B.'' ser. ''Coccineae'' (1 species) ::: ''B.'' sect. ''Oncostylis'' (3 series, 21 species) :: ''B.'' subg. ''Isostylis'' (2 species)

Thiele and Ladiges 1996

In 1996, Kevin Thiele and

undertook a cladistic analysis of morphological characters of ''Banksia'', which yielded a

phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

somewhat at odds with George's taxonomic arrangement. Their cladogram included a

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

consisting of the members of George's ''B.'' ser. ''Banksia'', together with the four members of ''B.'' ser. ''Crocinae'': Botanical Magazine 4906 BANKSIA Victoriæ

''B.'' ser. ''Crocinae'' was found to be monophyletic, but ''B.'' ser. ''Banksia'' was

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

with respect to it. To resolve this, Thiele and Ladiges abandoned ''B.'' ser. ''Crocinae'', transferring its four taxa into ''B.'' ser. ''Banksia''. They then divided ''B.'' ser. ''Banksia'', into two subseries, with the species belonging to George's ''B.'' ser. ''Crocinae'' endind up in ''B.'' subser. ''Cratistylis''.

George 1999

Thiele and Ladiges' arrangement remained current only until 1999, when George's treatment of the genus for the '' Flora of Australia'' series of monographs was published. This was essentially a revision of George's 1981 arrangement, which took into account some of Thiele and Ladiges' data, but rejected their overall arrangement. With respect to ''B.'' ser. ''Cyrtostylis'', George's 1999 arrangement was identical to his 1981 arrangement, except that ''B. burdettii'' and ''B. victoriae'' were exchanged in phyletic order.

Recent developments

Since 1998, Austin Mast has been publishing results of ongoing cladistic analyses of

DNA sequence DNA sequencing is the process of determining the nucleic acid sequence – the order of nucleotides in DNA. It includes any method or technology that is used to determine the order of the four bases: adenine, guanine, cytosine, and thymine. Th ...

data for the subtribe

Banksiinae ''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. ''Banksias'' range i ...

. His analyses suggest a

that is rather different to previous taxonomic arrangements. ''B.'' ser. ''Crocinae'' is monophyletic or nearly so, occurring in a

polytomous An internal node of a phylogenetic tree is described as a polytomy or multifurcation if (i) it is in a rooted tree and is linked to three or more child subtrees or (ii) it is in an unrooted tree and is attached to four or more branches. A tr ...

clade with '' B. menziesii''; this clade is sister to a clade containing '' B. sceptrum'' (Sceptre Banksia) and '' B. ashbyi'' (Ashby's Banksia), and a clade containing '' Banksia lindleyana'' (Porcupine Banksia): Early in 2007 Mast and Thiele initiated a rearrangement of ''Banksia'' by transferring ''Dryandra'' into it, and publishing ''B.'' subg. ''Spathulatae'' for the species having spoon-shaped

cotyledon A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The numb ...

s; in this way they also redefined the autonym ''B.'' subg. ''Banksia''. All members of ''B.'' ser. ''Crocinae'' fall within Mast and Thiele's ''B.'' subg. ''Banksia'', but no further details have been published. Mast and Thiele have foreshadowed publishing a full arrangement once DNA sampling of ''Dryandra'' is complete.

References

External links

* {{DEFAULTSORT:Banksia ser. Crocinae ser. Crocinae Eudicots of Western Australia Plant series