Commelinids Temporal range: | |
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Cock's-foot grass ( Dactylis glomerata ) | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Clade: | Commelinids |
Orders | |
Diversity [ citation needed ] | |
About 1,420 genera |
In plant taxonomy, commelinids (originally commelinoids [1] [2] ) is a clade of flowering plants within the monocots, distinguished by having cell walls containing ferulic acid. [3] [4]
The commelinids are the only clade that the APG IV system 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 and the lilioid monocots.
Members of the commelinid clade have cell walls containing UV-fluorescent ferulic acid. [3] [4]
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 (monocots). [5] 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.[ citation needed ]
The Takhtajan system treated this as one of six subclasses within the class Liliopsida (=monocotyledons). It consisted of the following:[ citation needed ]
subclass Commelinidae
superorder Bromelianae
order Bromeliales
order Velloziales
superorder Pontederianae
order Philydrales
order Pontederiales
order Haemodorales
superorder Zingiberanae
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
order Juncales
order Cyperales
superorder Poanae
order Flagellariales
order Restionales
order Centrolepidales
order Poales
The Cronquist system treated this as one of four subclasses within the class Liliopsida. It consisted of the following:[ citation needed ]
subclass Commelinidae
order Commelinales
order Eriocaulales
order Restionales
order Juncales
order Cyperales
order Hydatellales
order Typhales
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). [6] [7] The commelinids now constitute a well-supported clade within the monocots, [8] and this clade has been recognized in all four APG classification systems.
Cladogram 1: The phylogenetic composition of the monocots [9]
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The commelinids of APG II (2003) and APG III (2009) contain essentially the same plants as the commelinoids of the earlier APG system (1998). [8] In APG IV (2016) the family Dasypogonaceae is no longer directly placed under commelinids but instead a family of order Arecales. [9]
clade monocots :
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The current phylogeny and composition of the commelinids. [10] |
The Alismatales (alismatids) are an order of flowering plants including about 4,500 species. Plants assigned to this order are mostly tropical or aquatic. Some grow in fresh water, some in marine habitats. Perhaps the most important food crop in the order is the corm of the taro plant, Colocasia esculenta.
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.
The Dioscoreales are an order of monocotyledonous flowering plants in modern classification systems, such as the Angiosperm Phylogeny Group and the Angiosperm Phylogeny Web. Within the monocots Dioscoreales are grouped in the lilioid monocots, where they are in a sister group relationship with the Pandanales. The Dioscoreales must contain the family Dioscoreaceae which includes the yam (Dioscorea), some species of which are an important food source in many regions. Older systems tended to place all lilioid monocots with reticulate veined leaves in Dioscoreales. As currently circumscribed by phylogenetic analysis using combined morphology and molecular methods, Dioscreales contains many reticulate veined vines in Dioscoraceae, it also includes the myco-heterotrophic Burmanniaceae and the autotrophic Nartheciaceae. The order consists of three families, 22 genera and about 850 species.
Liliales is an order of monocotyledonous flowering plants in the Angiosperm Phylogeny Group and Angiosperm Phylogeny Web system, within the lilioid monocots. This order of necessity includes the family Liliaceae. The APG III system (2009) places this order in the monocot clade. In APG III, the family Luzuriagaceae is combined with the family Alstroemeriaceae and the family Petermanniaceae is recognized. Both the order Lililiales and the family Liliaceae have had a widely disputed history, with the circumscription varying greatly from one taxonomist to another. Previous members of this order, which at one stage included most monocots with conspicuous tepals and lacking starch in the endosperm are now distributed over three orders, Liliales, Dioscoreales and Asparagales, using predominantly molecular phylogenetics. The newly delimited Liliales is monophyletic, with ten families. Well known plants from the order include Lilium (lily), tulip, the North American wildflower Trillium, and greenbrier.
The Poales are a large order of flowering plants in the monocotyledons, and includes families of plants such as the grasses, bromeliads, rushes and sedges. Sixteen plant families are currently recognized by botanists to be part of Poales.
The dicotyledons, also known as dicots, are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, that the seed has two embryonic leaves or cotyledons. There are around 200,000 species within this group. The other group of flowering plants were called monocotyledons, typically each having one cotyledon. Historically, these two groups formed the two divisions of the flowering plants.
Hydatellales is a botanical name for an order of flowering plants. In the Cronquist system, 1981, the name was used for an order placed in the subclass Commelinidae in class Liliopsida [=monocotyledons]. The order consisted of one family only:
LiliopsidaBatsch is a botanical name for the class containing the family Liliaceae. It is considered synonymous with the name monocotyledon. Publication of the name is credited to Scopoli : see author citation (botany). This name is formed by replacing the termination -aceae in the name Liliaceae by the termination -opsida.
Pandanales, the pandans or screw-pines, is an order of flowering plants placed in the monocot clade in the Angiosperm Phylogeny Group and Angiosperm Phylogeny Web systems. Within the monocots Pandanales are grouped in the lilioid monocots where they are in a sister group relationship with the Dioscoreales. Historically the order has consisted of a number of different families in different systems but modern classification of the order is based primarily on molecular phylogenetics despite diverse morphology which previously placed many of the families in other groupings based on apparent similarity. Members of the order have a subtropical distribution and includes trees, shrubs, and vines as well as herbaceous plants. The order consists of 5 families, 36 genera and about 1,610 species.
Burmanniaceae is a family of flowering plants, consisting of 99 species of herbaceous plants in eight genera.
The Xyridaceae are a family of flowering plants. This family has been recognized by many taxonomists and is known as the yellow-eyed grass family.
Haemodoraceae is a family of perennial herbaceous flowering plants with 14 genera and 102 known species. It is sometimes known as the "bloodroot family". Primarily a Southern Hemisphere family, they are found in South Africa, Australia and New Guinea, and in the Americas. Perhaps the best known are the widely cultivated and unusual kangaroo paws from Australia, of the two closely related genera Anigozanthos and Macropidia.
Plant taxonomy is the science that finds, identifies, describes, classifies, and names plants. It is one of the main branches of taxonomy.
The Thurniaceae are a family of flowering plants composed of two genera with four species. The botanical name has been recognized by most taxonomists.
The APG 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 Group. It was a revision of the first APG system, published in 1998, and was superseded in 2009 by a further revision, the APG III system.
The Rapateaceae are a family of flowering plants. The botanical name has been recognized by most taxonomists.
Hanguana is a genus of flowering plants with a dozen known species. It is the only genus in the family Hanguanaceae.
Centrolepidaceae are a family of flowering plants now included in Restionaceae following APG IV (2016). The botanical name has been recognized by most taxonomists.
Butomus is the only known genus in the plant family Butomaceae, native to Europe and Asia. It is considered invasive in some parts of the United States.
Lilioid monocots is an informal name used for a grade of five monocot orders in which the majority of species have flowers with relatively large, coloured tepals. This characteristic is similar to that found in lilies ("lily-like"). Petaloid monocots refers to the flowers having tepals which all resemble petals (petaloid). The taxonomic terms Lilianae or Liliiflorae have also been applied to this assemblage at various times. From the early nineteenth century many of the species in this group of plants were put into a very broadly defined family, Liliaceae sensu lato or s.l.. These classification systems are still found in many books and other sources. Within the monocots the Liliaceae s.l. were distinguished from the Glumaceae.