Cornales Temporal range: | |
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Dove tree in flower, a species in Nyssaceae | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Asterids |
Order: | Cornales Link [1] |
Families | |
The Cornales are an order of flowering plants, early diverging among the asterids, containing about 600 species. Plants within the Cornales usually have four-parted flowers, drupaceous fruits, and inferior to half-inferior gynoecia topped with disc-shaped nectaries.
In the classification system of Dahlgren the Cornales were in the superorder Corniflorae (also called Cornanae). Under the APG IV system, the Cornales order includes these families: [2]
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 age. [3]
The Cornales order is sister to the remainder of the large and diverse asterid 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. [4] Under the Cronquist system, the order comprised the families Cornaceae, Nyssaceae, Garryaceae, and Alangiaceae, and was placed among the Rosidae, but this interpretation is no longer followed. Many families and genera previously associated with the Cornales have been removed, including Garryaceae, Griselinia , Corokia , and Kaliphora , among others. [4]
Likely cladogram for Cornales: [5]
Molecular data suggest four clades are within the Cornales: Cornus-Alangium , nyssoids-mastixioids, Hydrangeaceae-Loasaceae, and Grubbia-Curtisia , with the Hydrostachyaceae in an uncertain position, possibly basal. [6] 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. [4] [6] [7] These difficulties in interpreting the systematics of Cornales may represent an early and rapid diversification of the groups within the order. [6]
The Apiales are an order of flowering plants. The families are those recognized in the APG III system. This is typical of the newer classifications, though there is some slight variation and in particular, the Torriceliaceae may also be divided.
Rosales is an order of flowering plants. It is sister to a clade consisting of Fagales and Cucurbitales. It contains about 7,700 species, distributed into about 260 genera. Rosales comprise nine families, the type family being the rose family, Rosaceae. The largest of these families are Rosaceae (91/4828) and Urticaceae (53/2625). The order Rosales is divided into three clades that have never been assigned a taxonomic rank. The basal clade consists of the family Rosaceae; another clade consists of four families, including Rhamnaceae; and the third clade consists of the four urticalean families.
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, although a few species are perennial herbs. Members of the family usually have opposite or alternate simple leaves, four- or five-parted flowers clustered in inflorescences or pseudanthia, and drupaceous fruits. The family is primarily distributed in northern temperate regions and tropical Asia. In northern temperate areas, Cornaceae are well known from the dogwoods Cornus.
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.
The Primulaceae, commonly known as the primrose family, are a family of herbaceous and woody flowering plants including some favourite garden plants and wildflowers. Most are perennial though some species, such as scarlet pimpernel, are annuals.
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:
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 discovered through phylogenetic studies.
Saxifragaceae is a family of herbaceous perennial flowering plants, within the core eudicot order Saxifragales. The taxonomy of the family has been greatly revised and the scope much reduced in the era of molecular phylogenetic analysis. The family is divided into ten clades, with about 640 known species in about 35 accepted genera. About half of these consist of a single species, but about 400 of the species are in the type genus Saxifraga. The family is predominantly distributed in the northern hemisphere, but also in the Andes in South America.
Garryaceae is a small family of plants known commonly as the silktassels. It contains two genera:
The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants (angiosperms) which are mainly characterized by having two seed leaves (cotyledons) upon germination. The term derives from dicotyledon. Previously, they were called tricolpates or non-magnoliid dicots by past authors. The current botanical terms were introduced in 1991, by evolutionary botanist James A. Doyle and paleobotanist Carol L. Hotton, to emphasize the later evolutionary divergence of tricolpate dicots from earlier, less specialized, dicots.
In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade. Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flowering plant species. Well-known plants in this clade include the common daisy, forget-me-nots, nightshades, the common sunflower, petunias, yacon, morning glory, lettuce, sweet potato, coffee, lavender, lilac, olive, jasmine, honeysuckle, ash tree, teak, snapdragon, sesame, psyllium, garden sage, table herbs such as mint, basil, and rosemary, and rainforest trees such as Brazil nut.
Peridiscaceae is a family of flowering plants in the order Saxifragales. Four genera comprise this family: Medusandra, Soyauxia, Peridiscus, and Whittonia., with a total of 12 known species. It has a disjunct distribution, with Peridiscus occurring in Venezuela and northern Brazil, Whittonia in Guyana, Medusandra in Cameroon, and Soyauxia in tropical West Africa. Whittonia is possibly extinct, being known from only one specimen collected below Kaieteur Falls in Guyana. In 2006, archeologists attempted to rediscover it, however, it proved unsuccessful.
The APG 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 APG II in 2003, APG III system in 2009 and APG IV system in 2016.
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 and small trees. Members of the subfamily Loasoideae are known to exhibit rapid thigmonastic stamen movement when pollinators are present.
Mastixia is a genus of about 19 species of resinous evergreen trees, usually placed in the family Cornaceae. Its range extends from India through Southeast Asia and New Guinea to the Solomon Islands. Mastixia species have alternate or opposite simple broad leaves, many-flowered inflorescences, and blue to purple drupaceous fruits.
Diplopanax is a genus of flowering trees placed in the family Cornaceae or Nyssaceae. Its two known extant species inhabit the wet tropical mountains of Vietnam and southern China. They are broad-leaved evergreen trees with woody fruits and white or yellow flowers.
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-moving water. They have tuberous roots, usually pinnately compound leaves, and highly reduced flowers on dense spikes.
Grubbia is a genus of flowering plants. It is the sole genus in the family Grubbiaceae. The genus has three species, all endemic to the Cape Floristic Region of South Africa. They are shrubs that grow to 1.5 m (4.9 ft) tall, with tiny flowers and slender, leathery leaves. The fruit is a syncarp.
Suciacarpa is an extinct genus of asterid flowering plants in the order Cornales. It is known from the fossil species Suciacarpa starrii and Suciacarpa xiangae, both found in Western North America.