The Urticaceae are a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

, the nettle family, 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. The family name comes from the genus ''

Urtica ''Urtica'' is a genus of flowering plants in the family Urticaceae. Many species have stinging hairs and may be called nettles or stinging nettles, although the latter name applies particularly to ''Urtica dioica''. ''Urtica'' species are food f ...

''. The Urticaceae include a number of well-known and useful plants, including nettles in the genus ''Urtica'',

ramie Ramie (pronounced: , ; from Malay ) is a flowering plant in the nettle family Urticaceae, native to eastern Asia. It is a herbaceous perennial growing to tall;

(''Boehmeria nivea''), māmaki (''

Pipturus albidus ''Pipturus albidus'', known as ''māmaki'' (sometimes ''waimea'', for its resemblance to olomea) in Hawaiian and known as Waimea pipturus in English, is a species of flowering plant in the nettle family, Urticaceae, that is endemic to Hawaii. ...

''), and ajlai (''

Debregeasia saeneb ''Debregieasia saenab'', also known as ajilai, is a shrub that can reach a height of 1.5-2.4m. It has dark reddish branchlets and dark green leaves at mature form; the upper side of leaves are green and lower side are white-grey colour. It is an ...

''). The family includes about 2,625 species, grouped into 53 genera according to the database of the

Royal Botanic Gardens, Kew Royal Botanic Gardens, Kew is a non-departmental public body in the United Kingdom sponsored by the Department for Environment, Food and Rural Affairs. An internationally important botanical research and education institution, it employs 1,100 ...

and Christenhusz and Byng (2016). The largest genera are ''

Pilea ''Pilea'', with 600–715 species, is the largest genus of flowering plants in the nettle family Urticaceae. It is distributed throughout the tropics, subtropics, and warm temperate regions (with the exception of Australia and New Zealand). Des ...

'' (500 to 715 species), ''

Elatostema ''Elatostema'' is a genus of flowering plants containing approximately 350 known species in the nettle family Urticaceae, native to tropical forest clearings throughout Australasia, Asia and Africa. There may be as many as 1,000 species of this l ...

'' (300 species), ''

'' (80 species), and ''

Cecropia ''Cecropia'' is a Neotropical genus consisting of 61 recognized species with a highly distinctive lineage of dioecious trees. The genus consists of pioneer trees in the more or less humid parts of the Neotropics, with the majority of the speci ...

'' (75 species). ''

'' contains many

myrmecophytes Myrmecophytes (; literally "ant-plant") are plants that live in a mutualistic association with a colony of ants. There are over 100 different genera of myrmecophytes. These plants possess structural adaptations that provide ants with food and/o ...

. Urticaceae species can be found worldwide, apart from the polar regions.

Description

Urticaceae species can be shrubs (e.g. ''

''), lianas, herbs (e.g. ''

'', ''

Parietaria ''Parietaria'' is a genus of flowering plants in the family Urticaceae, native to temperate and tropical regions across the world.Flora Europaea''Parietaria''/ref>African Flowering Plants Database''Parietaria'' (enter genus name in search box)/ref ...

''), or, rarely, trees (''

Dendrocnide ''Dendrocnide'' is a genus of approximately 40 species of plants in the nettle family ''Urticaceae''. They have a wide distribution across North East India, Southeast Asia, Australia and the Pacific Islands. In Australia they are commonly known ...

'', ''

''). Their

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are usually entire and bear

stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

s. Urticating (stinging) hairs are often present. They have usually unisexual flowers and can be both

monoecious Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy. Monoecy is conne ...

dioecious Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...

. They are

wind-pollinated Anemophily or wind pollination is a form of pollination whereby pollen is distributed by wind. Almost all gymnosperms are anemophilous, as are many plants in the order Poales, including grasses, sedges, and rushes. Other common anemophilous plan ...

. Most disperse their

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

when the

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filame ...

s are mature and their filaments straighten explosively, a peculiar and conspicuously specialised mechanism.

Taxonomy

The

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 Gro ...

puts the Urticaceae in the order Rosales, while older systems consider them part of the

Urticales Urticales is an Order (biology), order of flowering plants. Before molecular phylogenetics became an important part of plant taxonomy, Urticales was recognized in many, perhaps even most, list of systems of plant taxonomy, systems of History of pla ...

, along with

Ulmaceae The Ulmaceae () are a family of flowering plants that includes the elms (genus ''Ulmus''), and the zelkovas (genus ''Zelkova''). Members of the family are widely distributed throughout the north temperate zone, and have a scattered distribution e ...

Moraceae The Moraceae — often called the mulberry family or fig family — are a family of flowering plants comprising about 38 genera and over 1100 species. Most are widespread in tropical and subtropical regions, less so in temperate climates; however ...

, and

Cannabaceae Cannabaceae is a small family (biology), family of flowering plants, known as the hemp family. As now Circumscription (taxonomy), circumscribed, the family includes about 170 species grouped in about 11 genera, including ''Cannabis'' (hemp), ''H ...

. APG still considers "old" Urticales a monophyletic group, but does not recognise it as an order on its own.

Fossil record

The

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

record of Urticaceae is scattered and mostly based on dispersed fruits. Twelve species based on fossil

achene An achene (; ), also sometimes called akene and occasionally achenium or achenocarp, is a type of simple dry fruit produced by many species of flowering plants. Achenes are monocarpellate (formed from one carpel) and indehiscent (they do not ope ...

s are known from the

Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the ...

Central Europe Central Europe is an area of Europe between Western Europe and Eastern Europe, based on a common historical, social and cultural identity. The Thirty Years' War (1618–1648) between Catholicism and Protestantism significantly shaped the area' ...

. Most were assigned to the extant genera ''

Boehmeria ''Boehmeria'' is a genus of 47 species of flowering plants in the nettle family Urticaceae. Of the species, 33 are indigenous to the Old World and 14 to the New World; no species is indigenous to both the Old and New Worlds. The species include h ...

'' (three species), ''

Debregeasia ''Debregeasia'' is a genus of plants belonging to the family Urticaceae The Urticaceae are a family, the nettle family, of flowering plants. The family name comes from the genus ''Urtica''. The Urticaceae include a number of well-known and ...

'' (one species) and ''

Pouzolzia ''Pouzolzia'' is a genus of flowering plants in the Urticaceae, nettle family. There are about 35 species distributed throughout the tropical world. Most are shrubs, and some are herbs. The genus was named for French botanist and plant collector ...

'' (three species), while three species were assigned to the

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus ''Urticoidea''. A Colombian fossil flora of the

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...

stage has yielded leaves that resemble leaves of the tribe Ceropieae. In the

Cenozoic The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configura ...

fossil leaves from the

Ypresian In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...

Allenby Formation The Allenby formation is a sedimentary rock formation in British Columbia which was deposited during the Ypresian stage of the Early Eocene. It consists of conglomerates, sandstones with interbedded shales and coal. The shales contain an abun ...

preserve distinct

trichome Trichomes (); ) are fine outgrowths or appendages on plants, algae, lichens, and certain protists. They are of diverse structure and function. Examples are hairs, glandular hairs, scales, and papillae. A covering of any kind of hair on a pla ...

s, and have been attributed to the Tribe Urticeae in the fossil record. The leaves had originally been identified as ''

Rubus ''Rubus'' is a large and diverse genus of flowering plants in the rose family, Rosaceae, subfamily Rosoideae, with over 1,350 species. Raspberries, blackberries, and dewberries are common, widely distributed members of the genus. Most of these ...

'' by earlier workers on the

Eocene Okanagan Highlands The Eocene Okanagan Highlands or Eocene Okanogan Highlands are a series of Early Eocene geological formations which span a transect of British Columbia, Canada, and Washington state, United States. Known for a highly diverse and detailed Paleoflo ...

, but Devore ''et al'' (2020) interpreted the preserved hairs along the stem and major veins as stinging trichomes, rather than simple hairs or thorns.

Phylogeny

Modern

molecular phylogenetics 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 ...

suggest the following relationships (see also ):

Tribes and genera

* Boehmerieae Gaudich. 1830 **'' Archiboehmeria'' C.J. Chen 1980 (1 sp.) **'' Astrothalamus'' C.B. Rob. 1911 (1 sp.) **''

'' Jacq. 1760 (80 spp.) **'' Chamabainia'' Wight 1853 (1–2 spp.) **'' Cypholophus'' Wedd. 1854 (15 spp.) **''

'' Gaudich. 1844 (4 spp.) **'' Gibbsia'' Rendle 1917 (2 spp.) **'' Gonostegia'' Turcz. 1846 (5 spp.) **'' Hemistylus'' Benth. 1843 (4 spp.) **'' Neodistemon'' Babu & A. N. Henry 1970 (1 sp.) **'' Neraudia'' Gaudich. 1830 (5 spp.) **'' Nothocnide'' Blume 1856 (4 spp.) **'' Oreocnide'' Miq. 1851 (15 spp.) **'' Phenax'' Wedd. 1854 (12 spp.) **''

Pipturus ''Pipturus'' is a flowering plant genus in the nettle family, Urticaceae. Selected species * ''Pipturus albidus'' (Hook. & Arn.) A.Gray ex H.Mann – ''Māmaki'' (Hawaii) * '' Pipturus arborescens'' ( Link) C.B.Rob., 1911 * '' Pipturus arg ...

'' Wedd. 1854 (30 spp.) **''

'' Gaudich. 1826

830 __NOTOC__ Year 830 ( DCCCXXX) was a common year starting on Saturday (link will display the full calendar) of the Julian calendar. Events By place Britain * King Wiglaf of Mercia regains control from Wessex, and returns to the throne.S ...

/small> (70 spp.) **''

Rousselia ''Rousselia'' is a genus of flowering plants belonging to the family Urticaceae The Urticaceae are a family, the nettle family, of flowering plants. The family name comes from the genus ''Urtica''. The Urticaceae include a number of well-know ...

'' Gaudich. 1826

/small> (3 spp.) **'' Sarcochlamys'' Gaudich. 1844 (1 sp.) * Cecropieae Gaudich. 1830 **''

'' Loefl. 1758 (70–80 spp.) **''

Coussapoa ''Coussapoa'' is a genus of flowering plants belonging to the family Urticaceae. Its native range is Mexico, Central & Southern Tropical America. Species: *''Coussapoa angustifolia'' *''Coussapoa arachnoidea'' *''Coussapoa argentea'' *''Co ...

'' Aubl. 1775 (>50 spp.) **''

Leucosyke ''Leucosyke'' is a genus of flowering plants belonging to the family Urticaceae. Its native range is Tropical and Subtropical Asia to Southern Pacific. Species: *''Leucosyke arcuatovenosa'' *''Leucosyke aspera'' *''Leucosyke benguetensis'' * ...

'' Zoll. & Moritzi 1845 (35 spp.) **''

Maoutia ''Maoutia'' is a genus of shrubs or small trees in the nettle family (Urticaceae). It is native to Malesia and the South Pacific. It is found in Fiji, Java, Lesser Sunda Islands, Maluku, New Guinea, Philippines, Ryukyu Islands, Samoa, Society ...

'' Wedd. 1854 (15 spp.) **'' Musanga'' R. Br. in Tuckey 1818 (2 spp.) **'' Myrianthus'' P. Beauv. 1804

805 __NOTOC__ Year 805 ( DCCCV) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. Events By place Byzantine Empire * Siege of Patras: Local Slavic tribes of the Peloponnese lay siege to ...

/small> (7 spp.) **'' Pourouma'' Aubl. 1775 (>50 spp.) * Elatostemateae Gaudich. 1830 **'' Aboriella'' Bennet (1 sp.) **''

Achudemia ''Achudemia'' is a genus of plants belonging to the family Urticaceae. It is sometimes also treated as a section of the genus ''Pilea ''Pilea'', with 600–715 species, is the largest genus of flowering plants in the nettle family Urticaceae. ...

'' Blume 1856 **''

'' J.R. Forst. & G. Forst. 1775 (300 spp.) **''

Gyrotaenia ''Gyrotaenia'' is a genus of plants in the family Urticaceae The Urticaceae are a family, the nettle family, of flowering plants. The family name comes from the genus ''Urtica''. The Urticaceae include a number of well-known and useful plant ...

'' Griseb. 1861 (4 spp.) **'' Lecanthus'' Wedd. 1854 (1 sp.) **'' Meniscogyne'' Gagnep. 1928 (2 spp.) **'' Myriocarpa'' Benth. 1844

846 __NOTOC__ Year 846 ( DCCCXLVI) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. Events By place Byzantine Empire * Byzantine–Bulgarian War: The Bulgarians violate the peace treaty ...

/small> (18 spp.) **'' Pellionia'' Gaudich. 1826 (60 spp.) **''

Petelotiella ''Petelotiella'' is a monotypic genus of flowering plants belonging to the family Urticaceae. It contains just one species, ''Petelotiella tonkinensis''. It is native to Vietnam. The genus name of ''Petelotiella'' is in honour of Paul Alfred ...

'' Gagnep. in Lecomte 1929 (1 spp.) **''

'' Lindl. 1821 (250 spp.) **''

Procris In Greek mythology, Procris ( grc, Πρόκρις, ''gen''.: Πρόκριδος) was an Athenian princess as the third daughter of Erechtheus, king of Athens and his wife, Praxithea, daughter of Phrasimus and Diogeneia. Homer mentions her in t ...

'' Comm. ex Juss. 1789 (20 spp.) **'' Sarcopilea'' Urb. 1912 (1 sp.) * Forsskaoleeae Gaudich. 1830 **'' Australina'' Gaudich. 1830 (2 spp.) **'' Didymodoxa'' E. Mey. ex Wedd. 1857 (2 spp.) **'' Droguetia'' Gaudich. 1830 (7 spp.) **''

Forsskaolea ''Forsskaolea'' is a small genus of 7 species of perennial herbs in the nettle family with non-stinging hairs and dot-like concretions of mineral matter on their green parts. The genus was named in honor of Swedish botanist Peter Forsskål. De ...

'' L. 1764 (6 spp.) * Parietarieae Gaudich. 1830 **''

Gesnouinia ''Gesnouinia'' is a small genus of flowering plants in the family Urticaceae (the nettle family). Two species are accepted by The Plant List :Search for "Gesnouinia", * ''Gesnouinia arborea'' (L.f.) Gaudich. * ''Gesnouinia filamentosa'' Wedd. ...

'' Gaudich. 1830 (2 spp.) **''

'' L. 1753 (20 spp.) **''

Soleirolia ''Soleirolia soleirolii'' (, syn. ''Helxine soleirolii'') is a plant in the Urticaceae, nettle family. It has a number of common names, including baby's tears, angel's tears, peace in the home, bits and pieces, bread and cheese, Corsican creeper ...

'' Gaudich. 1830 (1 sp.) * Urticeae Lamarck & DC. 1806 **''

'' Miq. 1851 (27 spp.) **'' Discocnide'' Chew 1965 (1 sp.) **''

Girardinia ''Girardinia'' is a genus of flowering plants belonging to the family Urticaceae. Its native range is the tropical and subtropical Old World to Russian Far East. It is found in the countries of Angola, Assam, Bangladesh, Burundi, Cameroon, China, ...

'' Gaudich. 1830 (2 spp.) **''

Hesperocnide ''Hesperocnide'' is a small genus of nettles containing two species. These are annual herbs covered in stinging hairs and toothed leaves. ''Hesperocnide sandwicensis'', the Hawaii nettle, is endemic to Hawaii. '' Hesperocnide tenella'', the wes ...

'' Torr. 1857 (2 spp.) **''

Laportea ''Laportea'' is a genus of plants in the family Urticaceae. They are herbaceous, either annual or perennial. Like many plants of the Urticaceae, they have stinging hairs. There are stinging and non-stinging hairs on the same plant. The genus was ...

'' Gaudich. 1826

/small> (21 spp.) **'' Nanocnide'' Blume 1856 (2 spp.) **''

Obetia ''Obetia'' is a genus of dioecious plants in the family Urticaceae The Urticaceae are a family, the nettle family, of flowering plants. The family name comes from the genus ''Urtica''. The Urticaceae include a number of well-known and usefu ...

'' Gaudich. 1844 (7 spp.) **''

Poikilospermum ''Poikilospermum'' is a genus of shrubs or tall woody climbers, consisting of at least 33 accepted species. The plants are found from India and China (Yunnan), the Sino-Himalayan region to Sulawesi and Jawa in Indonesia. Some of the plants are u ...

'' Zipp. ex Miq. 1864 (20 spp.) **'' Touchardia'' Gaudich. 1847 (1–2 spp.) **''

Urera ''Urera'' is a genus of flowering plants in the nettle family, Urticaceae. It has a pantropical distribution.Steinmann, V. W. (2005)Four new neotropical species and a new combination of ''Urera'' (Urticaceae).''Acta Botánica Mexicana'' (71), 19- ...

'' Gaudich. 1826

/small> (35 spp.) **''

'' L. 1753—nettle (80 spp.) **'' Zhengyia'' T. Deng, D.G. Zhang & H. Sun 2013 (1 sp.) *''

Incertae sedis ' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty ...

'' **'' Metatrophis'' F. Br. 1935 (1 sp.) **'' Parsana'' Parsa & Maleki 1952 (1 sp.)

Diseases

The Urticaceae are subject to many bacterial, viral, fungal, and nematode parasitic diseases. Among them are: * Bacterial leaf spot, caused by ''

Xanthomonas campestris ''Xanthomonas campestris'' is a bacterium that causes a variety of plant diseases, including "black rot" in cruciferous vegetables and bacterial wilt of turfgrass. It is also used in the commercial production of xanthan gum, a high-molecular-w ...

'' which affects '' Pellionia'', ''

'', and other genera *

Anthracnose A plant canker is a small area of dead tissue, which grows slowly, often over years. Some cankers are of only minor consequence, but others are ultimately lethal and therefore can have major economic implications for agriculture and horticultur ...

, a fungal disease caused by ''

Colletotrichum capsici ''Colletotrichum capsici'' is a species of fungus and plant pathogen which causes leaf blight on ''Chlorophytum borivilianum'', basil, chickpea and pepper as well as dieback in pigeonpea The pigeon pea (''Cajanus cajan'') is a perennial legume ...

'' which affects ''Pilea'' * Myrothecium leaf spot, a fungal disease caused by ''

Myrothecium roridum ''Myrothecium roridum'' is a fungal plant pathogen Plant pathology (also phytopathology) is the scientific study of diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organi ...

'' which affects plants throughout the Urticaceae, as well as other angiosperms * Phytophthora blight, a

water mold Oomycota forms a distinct phylogenetic lineage of fungus-like eukaryotic microorganisms, called oomycetes (). They are filamentous and heterotrophic, and can reproduce both sexually and asexually. Sexual reproduction of an oospore is the result ...

disease caused by ''

Phytophthora nicotianae ''Phytophthora nicotianae'' or black shank is an oomycete belonging to the order Peronosprales and family Peronosporaceae. Hosts and symptoms ''Phytophthora nicotianae'' has a broad host range comprising 255 genera from 90 families. Hosts inclu ...

'' which affects ''Pilea'' * Southern blight, a fungal disease caused by ''

Athelia rolfsii ''Athelia rolfsii'' is a corticioid fungus in the family Atheliaceae. It is a facultative plant pathogen and is the causal agent of "southern blight" disease in crops. Taxonomy The species was first described in 1911 by Italian mycologist Pier ...

'' which affects both ''Pellionia'' and ''Pilea''

Image gallery

Image:PileaCadierei.jpg, ''Pilea cadierei'' Image:Pilea pumila2.JPG, ''Pilea pumila'' Image:Poisonivy1.jpg, ''Dendrocnide'' sp. Image:Elatostema umbellatum 2006.04.19 06.17.14-p4190208.jpg, ''Elatostema umbellatum'' Image:Brennnessel 1.JPG, ''Urtica dioica'' Image:Boehmeria nivea 1.jpg, ''Boehmeria nivea'' Image:Parietaria judaica 000.jpg, ''Parietaria judaica'' flowers Image:Nettle.jpg, ''Urtica dioica'' stinging hairs File:咬人狗 Dendrocnide meyeniana 20221020185903 03.jpg, Leaves of ''

Dendrocnide meyeniana ''Dendrocnide meyeniana'' or the poisonous wood nettle is a species of tree in the family Urticaceae, native to the thickets and secondary forests of Taiwan and the Philippines. The specific epithet ''meyeniana'' comes from Meiyuan/眉原, a pl ...

'' File:蕁麻(咬人貓) Urtica thunbergiana 20220406201651.jpg, The dotted bumps on the leaves of ''

Urtica thunbergiana ''Urtica thunbergiana'', also known as the Japanese nettle or hairy nettle, is a species of perennial herbs in the family Urticaceae. It is found in Japan, China and Taiwan. The habitat of the species is moist forests in the mountains. It is in ...

References

External links

* continuously updated. {{Taxonbar, from=Q156332 Rosid families

Description

Taxonomy

Fossil record

Phylogeny

Tribes and genera

Diseases

Image gallery

References

Further reading

External links