Plants named in 1818

Passiflora edulis, commonly known as passion fruit, is a vine species of passion flower native to southern Brazil, through Paraguay, and northern Argentina. The fruit is a pepo, a type of botanical berry, round to oval, either yellow or dark purple at maturity, with a soft to firm, juicy interior filled with numerous seeds. The plant is cultivated commercially in tropical and subtropical areas for its sweet, seedy fruit. This is both eaten and juiced, with the juice often added to other fruit juices to enhance aroma.

The Anacardiaceae, commonly known as the cashew family or sumac family, are a family of flowering plants, including about 83 genera with about 860 known species. Members of the Anacardiaceae bear fruits that are drupes and in some cases produce urushiol, an irritant. The Anacardiaceae include numerous genera, several of which are economically important, notably cashew (in the type genus Anacardium), mango, Chinese lacquer tree, yellow mombin, Peruvian pepper, sumac, smoke tree, marula, and cuachalalate. The genus Pistacia (which includes the pistachio and mastic tree) is now included, but was

Linaceae is a family of flowering plants. The family is cosmopolitan, and includes about 250 species in 14 genera, classified into two subfamilies: the Linoideae and Hugonioideae.

Oxalidaceae, or the wood-sorrels family, is a family of five genera of flowering plants, with the great majority of the 570 species in the genus Oxalis. The flowers within this family tend to be perfect, and 5-parted with a superior ovary consisting of five fused carpels. Fruits of this family tend to be capsules or berries that are prominently 5-lobed such as the starfruit.

The Juglandaceae are an angiosperm family known as the walnuts. They are trees, or sometimes shrubs, in the order Fagales. Members of this family are native to the Americas, Eurasia, and Southeast Asia. The nine or ten genera in the family have a total of around 63 species, and include the commercially important nut-producing trees walnut (Juglans), pecan (Carya illinoinensis), and hickory (Carya). The Persian walnut, Juglans regia, is one of the major nut crops of the world. Walnut, hickory, and gaulin are also valuable timber trees while pecan wood is also valued as cooking fuel. The

Wisteria is a genus of flowering plants in the legume family, Fabaceae (Leguminosae). The genus includes four species of woody twining vines that are native to China, Japan, Korea, Vietnam, southern Canada, the Eastern United States, and north of Iran. They were later introduced to France, Germany and various other countries in Europe. Some species are popular ornamental plants. The genus name is also used as the English name, and may then be spelt 'wistaria'. In some countries in Western and Central Europe, Wisteria is also known by a variant spelling of the genus in which species were

Cephalanthera, abbreviated Ceph in horticultural trade, is a genus of mostly terrestrial orchids. Members of this genus have rhizomes rather than tubers. About 15 species are currently recognized, most of them native to Europe and Asia. The only species found in the wild in North America is Cephalanthera austiniae, the phantom orchid or snow orchid. Ecologically, this species is partially myco-heterotrophic. Some of the Eurasian species hybridise. Several of the European species have common names including the word "helleborine", though orchids in other genera are also called helleborines. In

Hamamelidaceae, commonly referred to as the witch-hazel family, is a family of flowering plants in the order Saxifragales. The clade consists of shrubs and small trees positioned within the woody clade of the core Saxifragales. An earlier system, the Cronquist system, recognized Hamamelidaceae in the Hamamelidales order.

Hickory is a common name for trees composing the genus Carya, which includes 19 species accepted by Plants of the World Online. Seven species are native to Southeast Asia in China, Indochina, and northeastern India (Assam), and twelve are native to North America. A number of hickory species are used for their edible nuts or for their wood.

Kerria japonica, commonly known as Japanese kerria or Japanese rose, is a deciduous, yellow-flowering shrub in the rose family (Rosaceae), native to China and Japan. It is the only species in the genus Kerria. In the wild, it grows in thickets on mountain slopes. Japanese kerria has been used for medicine and is also planted in gardens. A double-flowered cultivar, K. japonica 'Pleniflora', is commonly called bachelor's buttons. When cultivated in the Central-Southern U.S., the plant is usually called Yellow Rose of Texas. Although the genus Kerria is in the rose family, it is not a true rose.

Abelia is a genus of flowering plants in the honeysuckle family, Caprifoliaceae. The genus currently includes six species native to China, Taiwan, and Vietnam. The genus previously contained about 30 species and hybrids. Molecular phylogenetic studies showed that the genus was not monophyletic. Abelia section Zabelia was raised to the genus Zabelia, and the majority of Abelia species have been transferred to other genera, including Diabelia, Lonicera, and Vesalea.

Phytolaccaceae is a family of flowering plants. Though almost universally recognized by taxonomists, its circumscription has varied. It is also known as the Pokeweed family. The APG II system, of 2003 (unchanged from the APG system, of 1998), also recognizes this family and assigns it to the order Caryophyllales in the clade core eudicots. The family comprises five genera, totalling 33 known species. It is divided into the subfamilies Agdestioideae and Phytolaccoideae, with the former Rivinioideae in the Takhtajan system, now placed in its own family Petiveriaceae

Berberis aquifolium, the Oregon grape holly-leaved barberry, or Mahonia, is a North American species of flowering plant in the family Berberidaceae. It is an evergreen shrub growing up to 3 metres (10 ft) tall and 1.5 m (5 ft) wide. It has pinnate leaves consisting of spiny leaflets, exhibiting dense clusters of yellow flowers in early spring, followed by dark bluish-black berries. The berries are a part of the traditional diet of some indigenous peoples of the Pacific Northwest and the species serves as the state flower of Oregon.

Ipomoea pes-caprae, also known as bayhops, bay-hops, beach morning glory, railroad vine, or goat's foot, is a common pantropical creeping vine belonging to the family Convolvulaceae. It grows on the upper parts of beaches and endures salted air. It is one of the most common and most widely distributed salt tolerant plants and provides one of the best known examples of oceanic dispersal. Its seeds float and are unaffected by salt water. Originally described by Linnaeus, it was placed in its current genus by Robert Brown in 1818.

Chrysobalanaceae is a family of flowering plants, consisting of trees and shrubs in 27 genera and about 700 species of pantropical distribution with a centre of diversity in the Amazon. Some of the species contain silica in their bodies for rigidity and so the mesophyll often has sclerenchymatous idioblasts. The widespread species Chrysobalanus icaco produces a plum-like fruit and the plant is commonly known as the coco plum. The family was traditionally placed as subfamily Chrysobalanoideae in the rose family (Rosaceae) or as a family in the rose order and exceptionally as an order in

Calathea is a genus of flowering plants belonging to the family Marantaceae. They are commonly called calatheas or (like their relatives) prayer plants. About 200 species formerly assigned to Calathea are now in the genus Goeppertia. Calathea currently contains around 60 species. Native to the tropical Americas, many of the species are popular as pot plants due to their decorative leaves and, in some species, colorful inflorescences. The young leaves and bracts can retain pools of water called phytotelmata, that provide habitat for many invertebrates.

Olacaceae is a family of flowering plants in the order Santalales. They are woody plants, native throughout the tropical regions of the world. As of July 2021, the circumscription of the family varies; some sources maintain a broad family, others split it into seven segregate families.

Rubus ulmifolius is a species of wild blackberry known by the English common name elmleaf blackberry or thornless blackberry and the Spanish common name zarzamora. It is native to Europe and North Africa, and has also become naturalized in parts of the United States (especially California), Australia, and southern South America.

Connaraceae is a pan-tropical plant family of 12 genera and more than 180 species of largely evergreen trees, woody shrubs and climbers. The family was first described by Robert Brown in 1816 and the name has been conserved.

Mahonia is a formerly accepted genus of approximately 70 species of shrubs or, rarely, small trees with evergreen leaves in the family Berberidaceae, native to eastern Asia, the Himalaya, North America, and Central America. They are closely related to the genus Berberis and as of 2023 the majority of botanical sources list it as a synonym for Berberis. However, there is still disagreement among botanists, and as recently as 2017 papers have been published arguing for the validity of the genus. In addition, sources that are updated less frequently like the USDA Natural Resources Conservation

Aesculus × carnea, or red horse-chestnut, is a medium-sized tree, an artificial hybrid between A. pavia (red buckeye) and A. hippocastanum (horse-chestnut). Its origin uncertain, probably appearing in Germany before 1820. It is a popular tree in large gardens and parks; and is even present in Hyde Park, London. Aesculus × carnea's features are typically intermediate between the parent species, but it inherits the red flower color from A. pavia. Its showy flowers are borne in plumes on branch ends, blooming in spring and producing leathery fruit capsules in fall. It grows up to 40 feet (12 m)

Maclura is a genus of flowering plants in the mulberry family, Moraceae. It includes the inedible Osage orange, which is used as mosquito repellent and grown throughout the United States as a hedging plant. It is dioecious, with male and female flowers borne on separate plants. Maclura is closely related to the genus Cudrania, and hybrids between the two genera have been produced. Some botanists recognize a more broadly defined Maclura that includes species previously included in Cudrania and other genera of Moraceae. The genus likely originated in South America during the Paleogene.

Shepherdia, commonly called buffaloberry or bullberry, is a genus of small shrubs in the Elaeagnaceae family. The plants are native to northern and western North America. They are non-legume nitrogen fixers. Shepherdia is dioecious, with male and female flowers produced on separate plants.

Cephalaria is a genus of flowering plants in the family Caprifoliaceae. It includes 102 species native to southern Europe, western and central Asia, and northern and southern Africa. They are annual or perennial herbaceous plants growing to 0.8–2 m tall. Cephalaria species are used as food plants by the larvae of some Lepidoptera species including Schinia imperialis, which feeds exclusively on C. procera.

Brugmansia arborea, the angel's trumpet, is a species of flowering plant in the family Solanaceae. The IUCN has classed Brugmansia arborea as extinct in the wild.

Myosotis laxa is a species of flowering herb in the family Boraginaceae. This species of forget-me-not is known by several common names, including tufted forget-me-not, bay forget-me-not, small-flower forget-me-not, small-flowered forget-me-not, and smaller forget-me-knot. It has a circumboreal distribution, occurring throughout some parts of the Northern Hemisphere. It grows in many types of habitats, including moist and wet areas, and is sometimes aquatic, growing in shallow water. The American naturalist and poet Henry David Thoreau described Myosotis laxa as: The mouse-ear forget-me-not,

Quercus michauxii, the swamp chestnut oak, is a species of oak in the white oak section Quercus section Quercus in the beech family. It is native to bottomlands and wetlands in the southeastern and midwestern United States, in coastal states from New Jersey to Texas, inland primarily in the Mississippi–Ohio Valley as far as Oklahoma, Missouri, Illinois, and Indiana.

Potamogeton acutifolius is a European species of aquatic plant in the family Potamogetonaceae, known by the common name sharp-leaved pondweed. It is threatened and declining in at least part of its range.

Podocarpus macrophyllus is a conifer in the genus Podocarpus, family Podocarpaceae. It is the northernmost species of the genus, native to southern Japan and southern and eastern China. Common names in English include yew plum pine, Buddhist pine, fern pine and Japanese yew. Kusamaki (クサマキ) and inumaki (犬槇) are Japanese names for this tree. In China, it is known as luóhàn sōng (羅漢松), which literally means "arhat pine".

Araujia is a small genus of perennial vines in the dogbane family first described as a genus in 1817. The group is native to South America.