In plant taxonomy, commelinids (originally commelinoids
) (plural, not capitalised) is 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, ...
of
flowering plants within the
monocots, distinguished by having cell walls containing
ferulic acid.
The commelinids are the only clade that the
APG IV system has informally named within the monocots. The remaining monocots are a
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 ...
unit. Also known as the commelinid monocots it forms one of three groupings within the monocots, and the final branch; the other two groups are the
alismatid monocots and the
lilioid monocots
Lilioid monocots (lilioids, liliid monocots, petaloid monocots, petaloid lilioid monocots) is an informal name used for a grade (grouping of taxa with common characteristics) of five monocot orders (Petrosaviales, Dioscoreales, Pandanales, L ...
.
Description
Members of the commelinid clade have
cell wall
A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mech ...
s containing
UV-
fluorescent ferulic acid.
Taxonomy
The commelinids were first recognized as a formal group in 1967 by
Armen Takhtajan
Armen Leonovich Takhtajan or Takhtajian ( hy, Արմեն Լևոնի Թախտաջյան; russian: Армен Леонович Тахтаджян; surname also transliterated Takhtadjan, Takhtadzhi︠a︡n or Takhtadzhian, pronounced takh-tuh-JA ...
, who named them the Commelinidae and assigned them to a subclass of
Liliopsida (monocots).
The name was also used in the 1981
Cronquist system. However, by the release of his 1980 system of classification, Takhtajan had merged this subclass into a larger one, and no longer considered it to be a clade.
Takhtajan system
The
Takhtajan system treated this as one of six subclasses within the class
Liliopsida (=
monocotyledons). It consisted of the following:
subclass Commelinidae
superorder
Bromelianae
Bromeliales is an order of flowering plants. Such an order has been recognized by a few systems of plant taxonomy, with a various placement. It appears that it always has had the same circumscription:
consisting only of the family Bromeliacea ...
order
Bromeliales
order
Velloziales
superorder
Pontederianae
order
Philydrales
order
Pontederiales
order
Haemodorales
superorder
Zingiberanae
The Zingiberales are flowering plants forming one of four orders in the commelinids clade of monocots, together with its sister order, Commelinales. The order includes 68 genera and 2,600 species. Zingiberales are a unique though morpho ...
order
Musales
order
Lowiales
order
Zingiberales
order
Cannales
superorder
Commelinanae
order
Commelinales
order
Mayacales
order
Xyridales
order
Rapateales
order
Eriocaulales
superorder
Hydatellanae
order
Hydatellales
superorder
Juncanae
Lilianae (also known as Liliiflorae) is a botanical name for a superorder (that is, a rank higher than that of order) of flowering plants. Such a superorder of necessity includes the type family Liliaceae (and usually the type order Liliales). ...
order
Juncales
Juncales is an order of flowering plants. In the Engler system (update, of 1964) and in the Cronquist system (of 1981, which placed this order in subclass Commelinidae) it is circumscribed as:
* order Juncales
*: family Juncaceae
*: family Thur ...
order
Cyperales
superorder
Poanae
order
Flagellariales
order
Restionales
order
Centrolepidales
order
Poales
Cronquist system
The
Cronquist system treated this as one of four subclasses within the class Liliopsida. It consisted of the following:
subclass Commelinidae
order
Commelinales
order
Eriocaulales
order
Restionales
order
Juncales
Juncales is an order of flowering plants. In the Engler system (update, of 1964) and in the Cronquist system (of 1981, which placed this order in subclass Commelinidae) it is circumscribed as:
* order Juncales
*: family Juncaceae
*: family Thur ...
order
Cyperales
order
Hydatellales
order
Typhales
APG system
The
APG II system does not use formal botanical names above the
rank of order; most of the members were assigned to the clade commelinids in the monocots (its predecessor, the
APG system used the clade commelinoids).
The commelinids now constitute a well-supported clade within the monocots,
and this clade has been recognized in all four APG classification systems.
Subdivision
The commelinids of APG II (2003) and
APG III (2009) contain essentially the same plants as the commelinoids of the earlier
APG system (1998).
In
APG IV (2016) the family
Dasypogonaceae is no longer directly placed under commelinids but instead a family of order
Arecales.
References
Bibliography
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External links
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{{Taxonbar, from=Q868546, from2=Q1115272
Plant unranked clades