Commelinales is an order 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. It comprises five families:

Commelinaceae Commelinaceae is a family of flowering plants. In less formal contexts, the group is referred to as the dayflower family or spiderwort family. It is one of five families in the order Commelinales and by far the largest of these with about 731 kno ...

, Haemodoraceae, Hanguanaceae, Philydraceae, and

Pontederiaceae Pontederiaceae is a family of flowering plants. The APG IV system of 2016 (unchanged from the APG III system of 2009, the APG II system of 2003 and the APG system of 1998) places the family in the order Commelinales, in the commelinid clade, ...

. All the families combined contain over 885 species in about 70 genera; the majority of species are in the

. Plants in the order share a number of synapomorphies that tie them together, such as a lack of mycorrhizal associations and tapetal

raphides Raphides (pronounced /ˈræfɪˌdiz/, singular raphide /ˈreɪfʌɪd/ or raphis) are needle-shaped crystals of calcium oxalate monohydrate ( prismatic monoclinic crystals) or calcium carbonate as aragonite ( dipyramidal orthorhombic crystals), ...

. Estimates differ as to when the Commelinales evolved, but most suggest an origin and diversification sometime during the mid- to late

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

. Depending on the methods used, studies suggest a range of origin between 123 and 73 million years, with diversification occurring within the group 110 to 66 million years ago. The order's closest relatives are in the

Zingiberales 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 morphologi ...

, which includes ginger, bananas,

cardamom Cardamom (), sometimes cardamon or cardamum, is a spice made from the seeds of several plants in the genera ''Elettaria'' and ''Amomum'' in the family Zingiberaceae. Both genera are native to the Indian subcontinent and Indonesia. They are r ...

, and others.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, November 2011.

Taxonomy

According to the most recent classification scheme, the

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 ...

of 2016, the order includes five families: *

* Haemodoraceae * Hanguanaceae * Philydraceae *

This is unchanged from the

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 ...

of 2009 and the

APG II 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 ...

of 2003, but different from the older

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 ...

of 1998, which did not include Hanguanaceae.

Previous classification systems

The older

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) ...

of 1981, which was based purely on morphological data, placed the order in subclass

Commelinidae In plant taxonomy, commelinids (originally commelinoids) (plural, not capitalised) is a clade of flowering plants within the monocots, distinguished by having cell walls containing ferulic acid. The commelinids are the only clade that the APG IV ...

of class

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 ...

and included the families

Mayacaceae ''Mayaca'' is a genus of flowering plants, often placed in its own family, the Mayacaceae (or Mayaceae in earlier systems). In the APG II system of 2003, it is assigned to the order Poales in the clade commelinids. The Cronquist system, of 1981, ...

Rapateaceae The Rapateaceae are a family of flowering plants. The botanical name has been recognized by most taxonomists. The APG II system of 2003 also recognizes this family, and assigns it to the order Poales in the clade commelinids, in the monocots. T ...

and

Xyridaceae 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. The APG II system, of 2003 (unchanged from the APG system of 1998), also recognizes this family, ...

. These families are now known to be only distantly related. In the classification system of Dahlgren the Commelinales were one of four orders in the superorder Commeliniflorae (also called Commelinanae), and contained five families, of which only Commelinaceae has been retained by the

Angiosperm Phylogeny Group The Angiosperm Phylogeny Group (APG) is an informal international group of systematic botanists who collaborate to establish a consensus on the taxonomy of flowering plants (angiosperms) that reflects new knowledge about plant relationships disc ...

(APG).

References

* * {{Taxonbar, from=Q290349 Angiosperm orders Extant Campanian first appearances