Lactuca
Lettuce | |
---|---|
Lactuca tuberosa | |
Scientific classification | |
Kingdom: | Plantae |
(unranked): | Angiosperms |
(unranked): | Eudicots |
(unranked): | Asterids |
Order: | Asterales |
Family: | Asteraceae |
Tribe: | Cichorieae |
Genus: | Lactuca L. |
Lactuca, commonly known as lettuce, is a genus of flowering plants in the daisy 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.[1] Their flower heads 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.[1]
Diversity
There are different concepts of the species Lactuca. It is not clear how many distinct species are known, and estimates vary from 50[2] to 75,[3] so far.
- Lactuca acanthifolia (Crete, Turkey)
- Lactuca aculeata (Asia Minor)
- Lactuca acuminata
- Lactuca adenophora
- Lactuca alpestris (Crete)
- Lactuca alpina (syn. Cicerbita alpina)[6] (Europe) - alpine blue sow thistle, tall blue lettuce
- Lactuca altaica (Eurasia)
- Lactuca attenuata[7] (Africa)
- Lactuca aurea (Europe)
- Lactuca azerbaijanica (Iran)
- Lactuca biennis (North America) - tall blue lettuce, blue wood lettuce
- Lactuca calophylla (Africa)
- Lactuca canadensis (North America) - Canada wild lettuce, tall lettuce
- Lactuca corymbosa (Congo)
- Lactuca crambifolia (Turkestan)
- Lactuca deltoidea
- Lactuca dissecta (Asia)
- Lactuca dolichophylla (Asia)
- Lactuca dregeana (South Africa) - melkdissel, slaaidissel
- Lactuca dumicola
- Lactuca erostrata[8] (Pakistan)
- Lactuca fenzlii
- Lactuca floridana (North America) - Florida lettuce, woodland lettuce
- Lactuca georgica (Asia)
- Lactuca glaucifolia (Asia)
- Lactuca graciliflora (Asia)
- Lactuca graminifolia (Americas) - grassleaf lettuce
- Lactuca haimanniana
- Lactuca henryi
- Lactuca hirsuta (North America) - downy lettuce, hairy lettuce
- Lactuca hispida
- Lactuca homblei[9] (Zaire, Zambia)
- Lactuca imbricata[10] (Africa)
- Lactuca indica (Asia) - Indian lettuce
- Lactuca inermis (Africa, Arabian Peninsula)
- Lactuca intricata (Albania, Greece, Turkey)
- Lactuca jamaicensis (Jamaica)
- Lactuca kanitziana
- Lactuca kochiana
- Lactuca lasiorhiza[11] (Africa)
- Lactuca ludoviciana (North America) - biannual lettuce
- Lactuca mira
- Lactuca muralis
- Lactuca mwinilungensis[12] (Zaire, Zambia)
- Lactuca nana[13] (Africa)
- Lactuca orientalis (Asia, Egypt)
- Lactuca palmensis[14] (Canary Islands)
- Lactuca paradoxa
- Lactuca parishii
- Lactuca perennis (Europe) - blue lettuce, mountain lettuce
- Lactuca persica
- Lactuca petrensis
- Lactuca quercina (Eurasia)
- Lactuca racemosa
- Lactuca raddeana (Asia)
- Lactuca rechingeriana
- Lactuca rosularis (Iran, Turkmenistan)
- Lactuca saligna (Eurasia) - willow lettuce, least lettuce, narrow-leaf lettuce
- Lactuca sativa - lettuce, garden lettuce
- Lactuca scarioloides (western Asia)
- Lactuca schulzeana (Angola, Cameroon, Zaire)
- Lactuca schweinfurthii (Africa)
- Lactuca serriola (Africa, Asia, Europe) - prickly lettuce, compassplant, scarole, milk thistle
- Lactuca setosa (Africa)
- Lactuca sibirica (Eurasia)
- Lactuca singularis[15] (Spain)
- Lactuca songeensis
- Lactuca spinidens (Tajikistan, Turkmenistan)
- Lactuca stebbinsii[16] (Angola)
- Lactuca takhtadzhianii (Armenia)
- Lactuca tatarica (Northern Hemisphere) - blue lettuce
- Lactuca tenerrima (southern Europe, Morocco)
- Lactuca tetrantha[17] (Cyprus)
- Lactuca tinctociliata
- Lactuca triangulata (Asia)
- Lactuca triquetra
- Lactuca tuberosa (Eurasia)
- Lactuca ugandensis
- Lactuca undulata (Asia)
- Lactuca viminea (Africa, Asia, Europe) - pliant lettuce
- Lactuca virosa (Europe, northern Africa) - bitter lettuce, great lettuce
- Lactuca watsoniana[18] (Azores)
- Lactuca winkleri (Tajikistan)
Ecology
Lactuca species are used as food plants by the larvae of many Lepidoptera species.
Footnotes
- ↑ 1.0 1.1 Lebeda, A., et al. (2004). Geographical distribution of wild Lactuca species (Asteraceae, Lactuceae). The Botanical Review 70(3) 328-56.
- ↑ 2.0 2.1 Lactuca. Flora of China.
- ↑ 3.0 3.1 Lactuca. Flora of North America.
- ↑ GRIN Species Records of Lactuca. Germplasm Resources Information Network (GRIN).
- ↑ Lactuca. The Plant List. Royal Botanic Gardens, Kew, and Missouri Botanical Garden.
- ↑ Cicerbita alpina. Germplasm Resources Information Network (GRIN).
- ↑ Lactuca attenuata. Flora Zambesiaca. Royal Botanic Gardens, Kew.
- ↑ 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.
- ↑ Lactuca homblei. Flora Zambesiaca. Royal Botanic Gardens, Kew.
- ↑ Lactuca imbricata. Flora Zambesiaca. Royal Botanic Gardens, Kew.
- ↑ Lactuca lasiorhiza. Flora Zambesiaca. Royal Botanic Gardens, Kew.
- ↑ Lactuca mwinilungensis. Flora Zambesiaca. Royal Botanic Gardens, Kew.
- ↑ Lactuca nana. Flora Zambesiaca. Royal Botanic Gardens, Kew.
- ↑ Santos Guerra, A. 2011. Lactuca palmensis. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. Downloaded on 07 July 2013.
- ↑ Draper, D. 2011. Lactuca singularis. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. Downloaded on 07 July 2013.
- ↑ 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.
- ↑ Kyratzis, A., et al. 2011. Lactuca tetrantha. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. Downloaded on 07 July 2013.
- ↑ Schaefer, H. 2011. Lactuca watsoniana. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.1. Downloaded on 07 July 2013.