Ranunculales is an

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number 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 t ...

s. Of necessity it contains the family

Ranunculaceae Ranunculaceae (buttercup or crowfoot family; Latin "little frog", from "frog") is a family of over 2,000 known species of flowering plants in 43 genera, distributed worldwide. The largest genera are ''Ranunculus'' (600 species), ''Delphinium' ...

, the buttercup family, because the name of the order is based on the name of a genus in that family. Ranunculales belongs to a

paraphyletic group 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 ...

known as the basal eudicots. It is the most basal clade in this group; in other words, it is sister to the remaining eudicots. Widely known members include poppies, barberries, hellebores, and buttercups.

Taxonomy

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 ...

recognized seven families in Ranunculales in their

APG III system The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a fu ...

, published in 2009. In the preceding

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 ...

, they offered the option of three segregate families as shown below. * order Ranunculales *: family

Berberidaceae The Berberidaceae are a family of 18 genera of flowering plants commonly called the barberry family. This family is in the order Ranunculales. The family contains about 700 known species, of which the majority are in ''Berberis''. The species ...

*: family Circaeasteraceae *:: _family_Kingdoniaceae_.html" ;"title="Kingdoniaceae.html" ;"title=" family Kingdoniaceae"> family Kingdoniaceae ">Kingdoniaceae.html" ;"title=" family Kingdoniaceae"> family Kingdoniaceae *: family Eupteleaceae *: family

Lardizabalaceae Lardizabalaceae is a family of flowering plants. The family has been universally recognized by taxonomists, including the APG II system (2003; unchanged from the APG system of 1998), which places it in the order Ranunculales, in the clade eudic ...

*: family Menispermaceae *: family Papaveraceae *:: [+ family Fumariaceae ] *:: [+ family Pteridophyllaceae ] *: family

Note: "+ ..." = optionally separate family (that may be split off from the preceding family). Under this definition, well-known members of Ranunculales include

buttercup ''Ranunculus'' is a large genus of about almost 1700 to more than 1800 species of flowering plants in the family Ranunculaceae. Members of the genus are known as buttercups, spearworts and water crowfoots. The genus is distributed in Europe, ...

clematis ''Clematis'' is a genus of about 300 species within the buttercup family, Ranunculaceae. Their garden hybrids have been popular among gardeners, beginning with ''Clematis'' × ''jackmanii'', a garden standby since 1862; more hybrid cultivars ...

, columbines, delphiniums, and poppies. 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 s ...

of Ranunculales was published in 2009, based on

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

analysis 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. T ...

s. The authors of this

paper Paper is a thin sheet material produced by mechanically or chemically processing cellulose fibres derived from wood, rags, grasses or other vegetable sources in water, draining the water through fine mesh leaving the fibre evenly distribu ...

revised the subfamilies and

tribes The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide usage of the term in English is in the discipline of anthropology. This definition is contested, in part due to confli ...

of the order. This is reflected in the subsequent revision of the APG, APG IV (2016). The analysis revealed that the order consisted of three

clades 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 te ...

, Eupteleaceae, Papaveraceae and a third clade, considered to be the "core" Ranuculales, consisting of the remaining five families. The phylogeny of the families is shown in the cladogram.

Evolution

The fossil form '' Leefructus'', described in 2011, has been recognized as a member of this order.Fossil is best look yet at an ancestor of buttercups
/ref> ''Leefructus mirus'' shows fully developed leaves; stem and flower that are very similar in structure to those of the modern buttercups. The fossil is dated to 125 million years old and it not only proves that Ranunculales is an ancient group of

eudicots The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons. Traditionally they were called tricolpates or non-magnoliid dicot ...

but demonstrates that the whole

angiosperm 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 ...

clade may be older than expected. The structure of the plant and its age may lead to a new approach regarding the field that studies the evolution of

s. The fact that ''Leefructus'' shows a well-developed structure similar to modern ranunculids suggests that this group of eudicots may have developed earlier than the age of the fossil.

History

Historically the term

Ranales The Ranales are an obsolete taxon of the Dicotyledons, with rank of order typified by ''Ranunculus'' (Ranunculaceae). Description The Ranunculaceae were included directly in the Thalamiflorae by de Candolle (1819-1824) as an order within that su ...

was used to include the Ranunculaceae and related families, as described by Bentham and Hooker. This became replaced with Ranunculales by

Melchior Melchior is the name traditionally given to one of the biblical Magi appearing in the Gospel of Matthew. There are many notable people with this name, or close variations. As a first name * Melchior Anderegg (1828–1914), Swiss mountain guide * ...

in 1964. The

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) ...

(1981) also recognised the order, but placed it in the subclass Magnoliidae, in

class Class or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used differently ...

Magnoliopsida Magnoliopsida is a valid botanical name for a class of flowering plants. By definition the class will include the family Magnoliaceae, but its circumscription can otherwise vary, being more inclusive or less inclusive depending upon the classif ...

dicotyledons It used this circumscription: * order Ranunculales *: family

*: family Circaeasteraceae *: family

*: family Sargentodoxaceae *: family

*: family Menispermaceae *: family Coriariaceae *: family Sabiaceae In the Cronquist system, the Papaveraceae and Fumariaceae (including the plants in the optional family Pteridophyllaceae) were treated as a separate order Papaverales, placed in this same subclass Magnoliidae. The Cronquist circumscription of Ranunculales is now known to be

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of conver ...

. Sabiaceae is in a clade of basal eudicots separate from Ranunculales. Coriariaceae is now placed in the order Cucurbitales.

References

Bibliography

* * *

External links

NCBI Taxonomy Browser
{{Authority control Angiosperm orders Extant Aptian first appearances