The Cornales are 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, early diverging among the

asterids In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flowe ...

, containing about 600 species. Plants within the Cornales usually have four-parted flowers,

drupaceous In botany, a drupe (or stone fruit) is an indehiscent fruit in which an outer fleshy part (exocarp, or skin, and mesocarp, or flesh) surrounds a single shell (the ''pit'', ''stone'', or ''pyrena'') of hardened endocarp with a seed (''kernel'') ...

fruits, and inferior to half-inferior gynoecia topped with disc-shaped nectaries.

Taxonomy

In the classification system of Dahlgren the Cornales were in the superorder Corniflorae (also called Cornanae). Under 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 ...

, the Cornales order includes these families: *

Cornaceae The Cornaceae are a cosmopolitan family of flowering plants in the order Cornales. The family contains approximately 85 species in two genera, ''Alangium'' and ''Cornus''. They are mostly trees and shrubs, which may be deciduous or evergreen, alt ...

(the

dogwood ''Cornus'' is a genus of about 30–60 species of woody plants in the family Cornaceae, commonly known as dogwoods, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduous trees or shru ...

family) *

Curtisiaceae ''Curtisia dentata'' (commonly known as the Assegai tree or Cape lancewood, af, Assegaai, xh, Umgxina, zu, Umagunda) is a flowering tree from Southern Africa. It is the sole species in genus ''Curtisia'', which was originally classed as a typ ...

(cape lancewood) *

Grubbiaceae The Grubbiaceae are a family of flowering plants endemic to the Cape floristic region of South Africa. The family includes five species of leathery-leaved shrubs in two genera Genus ( plural genera ) is a taxonomic rank used in the biologica ...

(the

sillyberry The Grubbiaceae are a family of flowering plants endemic to the Cape floristic region of South Africa. The family includes five species of leathery-leaved shrubs in two genera Genus ( plural genera ) is a taxonomic rank used in the biologica ...

family) *

Hydrangeaceae Hydrangeaceae is a family of flowering plants in the order Cornales, with a wide distribution in Asia and North America, and locally in southeastern Europe. Description The genera are characterised by leaves in opposite pairs (rarely whorled ...

(the

hydrangea ''Hydrangea'', () commonly named the hortensia, is a genus of over 75 species of flowering plants native to Asia and the Americas. By far the greatest species diversity is in eastern Asia, notably China, Korea, and Japan. Most are shrubs tall, ...

family) *

Hydrostachyaceae ''Hydrostachys'' is a genus of about 22 species of flowering plants native to Madagascar and southern and central Africa. It is the only genus in the family Hydrostachyaceae. All species of ''Hydrostachys'' are aquatic, growing on rocks in fast-m ...

Loasaceae Loasaceae is a family of 15–20 genera and about 200–260 species of flowering plants in the order Cornales, native to the Americas and Africa. Members of the family include annual, biennial and perennial herbaceous plants, and a few shrubs ...

(the stickleaf family) *

Nyssaceae Nyssaceae is a family of flowering trees sometimes included in the dogwood family (Cornaceae). Nyssaceae is composed of 37 known species in the following five genera:Averyanov, L. V. & Hiep, N. T. (2002). ''Diplopanax vietnamensis'', a New Specie ...

, (the

tupelo Tupelo , genus ''Nyssa'' , is a small genus of deciduous trees with alternate, simple leaves. It is sometimes included in the subfamily Nyssoideae of the dogwood family, Cornaceae, but is placed by other authorities in the family Nyssaceae. In ...

s) The oldest fossils assigned with confidence to the order are '' Hironoia fusiformis'', described from Coniacian age Japanese coalified fruits, and '' Suciacarpa starrii'' described from American permineralized fruits of

Campanian The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campani ...

age.

Phylogeny

The Cornales order is sister to the remainder of the large and diverse

asterid In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flo ...

clade. The Cornales are highly geographically disjunct and morphologically diverse, which has led to considerable confusion regarding the proper circumscription of the groups within the order and the relationships between them.Xiang, Q. Y., Soltis, D. E., Morgan, D. R., and Soltis, P. S. (1993). Phylogenetic relationships of ''Cornus'' L ''sensu lato'' and putative relatives inferred from rbcL sequence data. ''Annals of the Missouri Botanical Garden'' 80, 723-734. Under 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) ...

, the order comprised the families Cornaceae, Nyssaceae,

Garryaceae Garryaceae is a small family of plants known commonly as the silktassels.Garryaceae.
Flora o ...

, and

Alangiaceae Alangiaceae was recognized as a small family of small dicotyledon trees, shrubs or lianas, closely related to the Cornaceae (dogwood family). There is only one genus, '' Alangium'', with seventeen species. The APG II states that Alangiaceae is ...

, and was placed among the

Rosidae Under the International Code of Nomenclature for algae, fungi, and plants (ICN), Rosidae is a botanical name at the rank of subclass. Circumscription of the subclass will vary with the taxonomic system being used; the only requirement being t ...

, but this interpretation is no longer followed. Many families and genera previously associated with the Cornales have been removed, including Garryaceae, '' Griselinia'', ''

Corokia ''Corokia'' is a genus in the Argophyllaceae family. The genus was first described in 1839. It comprising six species native to New Zealand, Australia and Rapa Iti. ''Corokia'' species are shrubs or small trees with zigzagging (divaricating) br ...

'', and '' Kaliphora'', among others. Likely cladogram for Cornales:Based on Figure 11.10 in Molecular data suggest four clades are within the Cornales: ''

Cornus ''Cornus'' is a genus of about 30–60 species of woody plants in the family Cornaceae, commonly known as dogwoods, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduous trees or shrub ...

Alangium ''Alangium'' is a small genus of flowering plants. The genus is included either in a broad view of the dogwood family Cornaceae, or as the sole member of its own family Alangiaceae.Qiu-Yun (Jenny) Xiang, David T. Thomas, and Qiao Ping Xiang. ...

'', nyssoids-mastixioids, Hydrangeaceae-Loasaceae, and '' Grubbia-

Curtisia ''Curtisia dentata'' (commonly known as the Assegai tree or Cape lancewood, af, Assegaai, xh, Umgxina, zu, Umagunda) is a flowering tree from Southern Africa. It is the sole species in genus ''Curtisia'', which was originally classed as a typ ...

'', with the Hydrostachyaceae in an uncertain position, possibly basal.Fan, C. Z., and Xiang, Q. Y. (2003). Phylogenetic analyses of Cornales based on 26S rRNA and combined 26S rDNA-matK-rbcL sequence data. ''American Journal of Botany'' 90, 1357-1372. However, the relationship between these clades is unclear, and as a result of many historical taxonomic interpretations and differing opinions regarding the significance of morphological variations, rankings of taxa within the order are inconsistent.Eyde, R. H. (1988). Comprehending ''Cornus'' - puzzles and progress in the systematics of the dogwoods. ''Botanical Review'' 54, 233-351. These difficulties in interpreting the systematics of Cornales may represent an early and rapid diversification of the groups within the order.

References

External links

* http://www.britannica.com/EBchecked/topic/137865/Cornales {{Taxonbar, from=Q21769 Angiosperm orders