''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce (''Lactuca sativa''), with its many varieties. "Wild lettuce" commonly refers to the wild-growing relatives of common garden lettuce. Many species are common weeds. ''Lactuca'' species are diverse and take a wide variety of forms. They are annuals, biennials, perennials, or shrubs. Their

flower heads A pseudanthium (Greek for "false flower"; ) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, compos ...

have yellow, blue, or white ray florets. Some species are bitter-tasting. Most wild lettuces are xerophytes, adapted to dry habitat types. Some occur in more moist areas, such as the mountains of central Africa.

Diversity

There are different concepts of the species within ''Lactuca''. It is not clear how many distinct species are known, and estimates vary from 50''Lactuca''.
Flora of China. to 75''Lactuca''.
Flora of North America. so far. Species include:GRIN Species Records of ''Lactuca''.
Germplasm Resources Information Network (GRIN).''Lactuca''.
The Plant List. Royal Botanic Gardens, Kew, and Missouri Botanical Garden. *'' Lactuca acanthifolia'' ( Crete, Turkey) *''

Lactuca aculeata ''Lactuca aculeata'' is a species of wild lettuce native to Anatolia, the Levant, Iraq and Iran. A very prickly plant, it is closely related to ''Lactuca serriola'' (prickly lettuce) and '' Lactuca sativa'' (cultivated or garden lettuce), and ...

'' ( Asia Minor) *''

Lactuca acuminata ''Lactuca floridana'', commonly known as woodland lettuce, Florida lettuce, or false lettuce is a North American species of wild lettuce. It is native across much of central Canada and the eastern and central United States. ''Lactuca floridana ...

'' *'' Lactuca adenophora'' *''

Lactuca alpestris ''Lactuca alpestris'' is a species of plant native to Crete in the Ida mountains and is a relative of lettuce. It is perennial and has yellow flowers. Its achenes are 7m to 8m long. The species grows on rocky slopes, dwarf shrub communities, ca ...

'' (Crete) *''Lactuca alpina'' (syn. '' Cicerbita alpina'') ( Europe) - alpine sow-thistle, alpine blue-sow-thistle, tall blue lettuce *'' Lactuca altaica'' (Eurasia) *'' Lactuca attenuata''''Lactuca attenuata''.
''Flora Zambesiaca''. Royal Botanic Gardens, Kew. (Africa) *'' Lactuca aurea'' (Europe) *'' Lactuca azerbaijanica'' ( Iran) *''

Lactuca biennis ''Lactuca biennis'' is a North American species of wild lettuce known by the common names tall blue lettuce and blue wood lettuce. It is widespread across much of the United States and Canada from Alaska and Yukon south as far as California, New ...

'' (North America) – tall blue lettuce, blue wood lettuce *''

Lactuca calophylla ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' (Africa) *'' Lactuca canadensis'' (North America) – Canada wild lettuce, tall lettuce *''

Lactuca corymbosa ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' (

Congo Congo or The Congo may refer to either of two countries that border the Congo River in central Africa: * Democratic Republic of the Congo, the larger country to the southeast, capital Kinshasa, formerly known as Zaire, sometimes referred to a ...

) *''

Lactuca crambifolia ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' ( Turkestan) *''

Lactuca cyprica ''Lactuca cypria'', the Cyprus lettuce, is a biennial, erect herb with glandular, hairy stems and a globose rhizome. Leaves alternate, simple, the basal large, oblong, petiolate, 10-15 x 5–7 cm, pinnatisect with a suborbicular terminal lo ...

'' ( Cyprus) - Cyprus lettuce *'' Lactuca deltoidea'' *''

Lactuca dissecta ''Lactuca dissecta'', the split-leaf lettuce, is an Asian species of plant in the tribe Cichorieae within the family Asteraceae. It is native to Central Asia, western China (Xinjiang, Tibet), the Himalayas, and southwest Asia as far west as Turke ...

'' (Asia) *''

Lactuca dolichophylla ''Lactuca dolichophylla'', the long-leaved lettuce, is a species of wild lettuce Wild lettuce is a common name for several lactucarium-containing plants related to lettuce (''Lactuca sativa''). The name most often refers to ''Lactuca virosa'' ( ...

'' (Asia) *''

Lactuca dregeana ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' ( South Africa) – ''melkdissel'', ''slaaidissel'' *''

Lactuca dumicola ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' *''

Lactuca erostrata ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

''Bano, R. and M. Qaiser. (2011)
A taxonomic revision of the genus ''Lactuca'' L. (Cichorieae-Asteraceae) from Pakistan and Kashmir.
''Pakistan Journal of Botany'' 43(5) 2259–268. ( Pakistan) *''

Lactuca fenzlii ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' *'' Lactuca floridana'' (North America) – Florida lettuce, woodland lettuce *''

Lactuca georgica ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' (Asia) *''

Lactuca glaucifolia ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' (Asia) *''

Lactuca graciliflora ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' (Asia) *''

Lactuca graminifolia ''Lactuca graminifolia'', the grassleaf lettuce is a North American species of wild lettuce. It grows in Mexico, Central America, Hispaniola, and the southern United States from Arizona to Florida, Virginia and the Carolinas. Description ''Lactu ...

'' (Americas) – grassleaf lettuce *''

Lactuca haimanniana ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' *''

Lactuca henryi ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' *'' Lactuca hirsuta'' (North America) – downy lettuce, hairy lettuce *'' Lactuca hispida'' *''

Lactuca homblei ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

''''Lactuca homblei''.
''Flora Zambesiaca''. Royal Botanic Gardens, Kew. ( Zaire, Zambia) *''

Lactuca imbricata ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

''''Lactuca imbricata''.
''Flora Zambesiaca''. Royal Botanic Gardens, Kew. (Africa) *''

Lactuca indica ''Lactuca indica'', the Indian lettuce, is a species of plant in the tribe Cichorieae whin the family Asteraceae. It is native to western China (Xinjiang, Tibet), the Himalayas, and southwest Asia as far west as Turkey Turkey ( tr, Tür ...

'' (Asia) - Indian lettuce *''

Lactuca inermis ''Lactuca inermis'' is a species of wild lettuce Wild lettuce is a common name for several lactucarium-containing plants related to lettuce (''Lactuca sativa''). The name most often refers to ''Lactuca virosa'' (Europe, Asia, introduced to Nort ...

'' (Africa,

Arabian Peninsula The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...

) *''

Lactuca intricata ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' (Albania, Greece, Turkey) *''

Lactuca jamaicensis ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the lettuce, garden ...

'' ( Jamaica) *''

Lactuca kanitziana ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the lettuce, garden ...

'' *'' Lactuca kochiana'' *''

Lactuca lasiorhiza ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

''''Lactuca lasiorhiza''.
''Flora Zambesiaca''. Royal Botanic Gardens, Kew. (Africa) *'' Lactuca ludoviciana'' (North America) – biannual lettuce *''

Lactuca macrophylla '' Lactuca macrophylla'' or ''Cicerbita macrophylla'', commonly known as common blue-sow-thistle, is a species of flowering plant in the family Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known specie ...

'' *''

Lactuca mira ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' *''

Lactuca muralis ''Lactuca muralis'', the wall lettuce, is a perennial flowering plant in the tribe Cichorieae within the family Asteraceae, also referred to as ''Mycelis muralis''.Parnell, J. and Curtis, T. 2012. ''Webb's An Irish Flora''. Cork University Press ...

'' *'' Lactuca mwinilungensis''''Lactuca mwinilungensis''.
''Flora Zambesiaca''. Royal Botanic Gardens, Kew. (Zaire, Zambia) *''

Lactuca nana ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

''''Lactuca nana''.
''Flora Zambesiaca''. Royal Botanic Gardens, Kew. (Africa) *''

Lactuca orientalis ''Lactuca orientalis'' is a Eurasian species of plant in the tribe Cichorieae within the family Asteraceae. It is widespread across the Middle East and southern Asia as far east as Tibet. ''Lactuca orientalis'' is a branching subshrub up to 6 ...

'' (Asia, Egypt) *''

Lactuca palmensis ''Lactuca palmensis'' is a species of wild lettuce endemic to the Canary Islands. DNA evidence shows that it is closely related to the African and European species of ''Lactuca'', while the Azores ) , motto =( en, "Rather die free than subjec ...

'' (

Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...

) *''

Lactuca paradoxa ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' *''

Lactuca parishii ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the lettuce, garden ...

'' *''

Lactuca perennis ''Lactuca perennis'', common names: mountain lettuce, blue lettuce or perennial lettuce, is a perennial herbaceous plant species belonging to the genus ''Lactuca'' of the family Asteraceae The family Asteraceae, alternatively Compositae, c ...

'' (Europe) – blue lettuce, mountain lettuce *''

Lactuca persica ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' *''

Lactuca petrensis ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' *'' Lactuca quercina'' (Eurasia) *'' Lactuca racemosa'' *''

Lactuca raddeana ''Lactuca raddeana'' is a species of wild lettuce Wild lettuce is a common name for several lactucarium-containing plants related to lettuce (''Lactuca sativa''). The name most often refers to ''Lactuca virosa'' (Europe, Asia, introduced to Nor ...

'' (Asia) *''

Lactuca rechingeriana ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' *''

Lactuca rosularis ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' (Iran, Turkmenistan) *''

Lactuca saligna ''Lactuca saligna'' is a species of wild lettuce known by the common name willowleaf lettuce, and least lettuce. It is native to Eurasia but it grows in many other places as an introduced species, including much of North America. It can be foun ...

'' (Eurasia) – willow lettuce, least lettuce, narrow-leaf lettuce *'' Lactuca sativa'' – lettuce, garden lettuce *''

Lactuca scarioloides ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' (western Asia) *''

Lactuca schulzeana ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' ( Angola, Cameroon, Zaire) *''

Lactuca schweinfurthii ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' (Africa) *''

Lactuca serriola ''Lactuca serriola'', also called prickly lettuce, milk thistle (not to be confused with ''Silybum marianum'', also called milk thistle), compass plant, and scarole, is an annual or biennial plant in the tribe Cichorieae within the family Asterac ...

'' (Africa, Asia, Europe) – prickly lettuce, compassplant, scarole, milk thistle *''

Lactuca setosa ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden let ...

'' (Africa) *''

Lactuca sibirica ''Lactuca sibirica'', the Siberian lettuce, is a species of wild lettuce Wild lettuce is a common name for several lactucarium-containing plants related to lettuce (''Lactuca sativa''). The name most often refers to ''Lactuca virosa'' (Europe, ...

'' (Eurasia) *''

Lactuca singularis ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' (Spain) *'' Lactuca songeensis'' *''

Lactuca spinidens ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' (Tajikistan, Turkmenistan) *''

Lactuca stebbinsii ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

''Kilian, N. (2001)
''Lactuca stebbinsii'' (Lactuceae, Compositae), a puzzling new species from Angola.
''Willdenowia - Annals of the Botanic Garden and Botanical Museum Berlin - Dahlem'' 31(1) 71–8. (Angola) *''

Lactuca takhtadzhianii ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' (Armenia) *'' Lactuca tatarica'' (Northern Hemisphere) – blue lettuce *''

Lactuca tenerrima ''Lactuca tenerrima'' is a species of wild lettuce native to southern France, Spain, the Balearic Islands, and the Atlas Mountains of Morocco. Unlike other species in its genus ''Lactuca'', even in its family Asteraceae, it does not produce bitte ...

'' (southern Europe, Morocco) *''

Lactuca tetrantha ''Lactuca tetrantha'', the Troödos lettuce, is an erect, lactiferous, perennial herb, 10–30 cm high. Leaves hairless, deeply dissected, the basal in rosette, oblong, 3-12 x 0.8-2.5 cm, often purplish-green, the upper alternate, small ...

'' (Cyprus) *''

Lactuca tinctociliata ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' *'' Lactuca triangulata'' (Asia) *''

Lactuca triquetra ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuce ...

'' *''

Lactuca tuberosa ''Lactuca tuberosa'' is an ornamental plant in the family Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly refer ...

'' (Eurasia) *''

Lactuca ugandensis ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' *'' Lactuca undulata'' (Asia) *''

Lactuca viminea ''Lactuca viminea'', the pliant lettuce, is a Eurasian plant species in the tribe Cichorieae within the family Asteraceae. It is widespread across much of Europe and southwestern Asia from Portugal to Pakistan.Lactuca virosa'' (Europe, northern Africa) – bitter lettuce, great lettuce *''

Lactuca watsoniana ''Lactuca watsoniana'', locally known as alfacinha, is a species of wild lettuce endemic to the Azores. An endangered species, there are fewer than 2000 individuals remaining in the wild. DNA evidence shows that it is closely related to the Nort ...

'' ( Azores) *''

Lactuca winkleri ''Lactuca'', commonly known as lettuce, is a genus of flowering plants in the family Asteraceae. The genus includes at least 50 species, distributed worldwide, but mainly in temperate Eurasia. Its best-known representative is the garden lettuc ...

'' (Tajikistan)

Ecology

''Lactuca'' species are used as food plants by the larvae of many Lepidoptera species.

Etymology

'Lactuca' is derived from Latin and means 'having milky sap'. 'Lactuca' and 'lactic' (of or relating to milk) have the same root word, 'lactis'.Gledhill, David (2008). "The Names of Plants". Cambridge University Press. (hardback), (paperback). pp 228

References

External links

Jepson Manual Treatment
{{Taxonbar, from=Q578052 Asteraceae genera