In plant taxonomy, commelinids (originally commelinoids) (plural, not capitalised) is a clade of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s within the

monocots Monocotyledons (), commonly referred to as monocots, ( Lilianae '' sensu'' Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of ...

, distinguished by having cell walls containing

ferulic acid Ferulic acid is a hydroxycinnamic acid, an organic compound with the formula (CH3O)HOC6H3CH=CHCO2H. The name is derived from the genus ''Ferula'', referring to the giant fennel ('' Ferula communis''). Classified as a phenolic phytochemical, ferul ...

. The commelinids are the only clade that the

APG IV system The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was published ...

has informally named within the monocots. The remaining monocots are a paraphyletic 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 Alismatid monocots (alismatids, basal monocots) is an informal name for a group of early branching (hence basal) monocots, consisting of two orders, the Acorales and Alismatales. The name has also been used to refer to the Alismatales alone. Mono ...

and the lilioid monocots.

Description

Members of the commelinid clade have cell walls containing UV-

fluorescent Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, ...

Taxonomy

The commelinids were first recognized as a formal group in 1967 by Armen Takhtajan, who named them the Commelinidae and assigned them to a subclass of

Liliopsida Liliopsida Batsch (synonym: Liliatae) is a botanical name for the class containing the family Liliaceae (or Lily Family). It is considered synonymous (or nearly synonymous) with the name monocotyledon. Publication of the name is credited to Scopol ...

(monocots). The name was also used in the 1981

Cronquist system The Cronquist system is a taxonomic classification system of flowering plants. It was developed by Arthur Cronquist in a series of monographs and texts, including ''The Evolution and Classification of Flowering Plants'' (1968; 2nd edition, 1988) ...

. 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 A system of plant taxonomy, the Takhtajan system of plant classification was published by Armen Takhtajan, in several versions from the 1950s onwards. It is usually compared to the Cronquist system. It admits paraphyletic groups. Systems The f ...

treated this as one of six subclasses within the class

(= monocotyledons). It consisted of the following: subclass Commelinidae superorder Bromelianae order

Bromeliales 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 Bromeliaceae ...

order Velloziales superorder Pontederianae order Philydrales order Pontederiales order Haemodorales superorder Zingiberanae order Musales order Lowiales order Zingiberales order

Cannales 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 morphologica ...

superorder Commelinanae order

Commelinales Commelinales is an order of flowering plants. It comprises five families: Commelinaceae, Haemodoraceae, Hanguanaceae, Philydraceae, and Pontederiaceae. All the families combined contain over 885 species in about 70 genera; the majority of sp ...

order Mayacales order

Xyridales The Poales are a large order of flowering plants in the monocotyledons, and includes families of plants such as the grasses, bromeliads, and sedges. Sixteen plant families are currently recognized by botanists to be part of Poales. Description ...

order Rapateales order Eriocaulales superorder Hydatellanae order Hydatellales superorder Juncanae order Juncales order Cyperales superorder Poanae order Flagellariales order Restionales order Centrolepidales order

Poales The Poales are a large order of flowering plants in the monocotyledons, and includes families of plants such as the grasses, bromeliads, and sedges. Sixteen plant families are currently recognized by botanists to be part of Poales. Descriptio ...

Cronquist system

The

treated this as one of four subclasses within the class Liliopsida. It consisted of the following: subclass Commelinidae order

order Eriocaulales order Restionales order Juncales order Cyperales order Hydatellales order

Typhales ''Typhales'' is a botanical name for an order of flowering plants. In the Cronquist system the name was used for an order placed in the subclass ''Commelinidae''. The order consisted of (1981): * order ''Typhales'' *: family ''Sparganiaceae'' *: ...

APG system

The

APG II system The APG II system (Angiosperm Phylogeny Group II system) of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Gr ...

does not use formal botanical names above the

rank Rank is the relative position, value, worth, complexity, power, importance, authority, level, etc. of a person or object within a ranking, such as: Level or position in a hierarchical organization * Academic rank * Diplomatic rank * Hierarchy * ...

of order; most of the members were assigned to the clade commelinids in the monocots (its predecessor, the

APG system The APG system (Angiosperm Phylogeny Group system) of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved A ...

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 APG is an abbreviation with several different meanings: * Aberdeen Proving Ground, a United States Army installation in Aberdeen, Maryland, also ** Phillips Army Airfield, the airfield of the above, from its IATA airport code * Aboriginal Provisiona ...

(2009) contain essentially the same plants as the commelinoids of the earlier

(1998). In

APG IV The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was publishe ...

(2016) the family Dasypogonaceae is no longer directly placed under commelinids but instead a family of order

Arecales Arecales is an order of flowering plants. The order has been widely recognised only for the past few decades; until then, the accepted name for the order including these plants was Principes. Taxonomy The APG IV system of 2016 places Dasypogo ...

Description

Taxonomy

Takhtajan system

Cronquist system

APG system

Subdivision

References

Bibliography

External links