Family:
Rutaceae Juss.

Citrus L.

This genus is accepted, and its native range is Himalaya to S. Central & S. Japan and Australia.

[FZ]

Rutaceae, F. A. Mendoça. Flora Zambesiaca 2:1. 1963

Morphology General Habit
Small trees or shrubs.
Morphology Leaves
Leaves 1-foliolate, with winged rhachis.
Morphology Reproductive morphology Flowers
Flowers bisexual, (4) 5-merous.
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens numerous, in phalanges.
Morphology Reproductive morphology Flowers Gynoecium Ovary
Ovary (4) 5-many-locular; loculi 4–8-ovulate.
Morphology Reproductive morphology Fruits
Fruit a large globose or ovoid or obovoid hesperidium, many-seeded and usually composed of numerous carpels.
Note
No indigenous species of Citrus are found in our area but some of the cultivated species (especially C. limon (L.) Burm. f. and C. aurantium L.) may become naturalized. Dr. G. R. Bates has kindly provided the appended note on the cultivation of Citrus in the Federation.

[FTEA]

Rutaceae, J.O. Kokwaro (University of Nairobi). Flora of Tropical East Africa. 1982

Morphology General Habit
Small evergreen shrubs or trees up to 10 m. high
Morphology Leaves
Leaves unifoliolate, with articulation between leaflet and petiole (except in C. medica); petiole normally winged
Morphology Reproductive morphology Flowers
Flowers single or in small clusters in leaf-axils, bisexual; calyx cup-shaped, 3–5-lobed; petals 4–8, normally 5, white; stamens numerous (20–40), in groups
Morphology Reproductive morphology Flowers Gynoecium Ovary
Ovary with 8–15 united carpels; locules 4–8-ovulate, with axile placentation
Morphology Reproductive morphology Fruits
Fruit a large globose, ovoid or obovoid berry known as a hesperidium, usually composed of many carpels, many-seeded.

[FSOM]

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit
Evergreen shrubs or trees; axillary spines usually present
Morphology Leaves
Leaves 1-foliolate, usually with petiole winged and articulated at the tip, gland-dotted
Morphology Reproductive morphology Flowers
Flowers usually bisexual, axillary, sometimes clustered, fragrant
Morphology Reproductive morphology Flowers Calyx
Calyx 3–5-lobed
Morphology Reproductive morphology Flowers Corolla
Petals (4–)5(–8), white
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 20–60, in bundles
Morphology Reproductive morphology Flowers Gynoecium Ovary
Ovary of 8–18 united carpels, each cell with 4–8 axile ovules
Morphology Reproductive morphology Fruits
Fruit a leathery-skinned berry known as a “hesperidium”, segmented and filled with inflated hair-cells full of juice.
Distribution
Cultivated
Note
Some 16 species of Asian origin, most of which may be ancient apomictic hybrids. The taxonomy of the genus is complex and confusing and new hybrids are continuously being produced also involving species in other genera.

[FSOM]
Use
The citrus fruits are of great economic importance, but in Somalia only grapefruit, lemon and lime are grown to any larger extent.

Native to:

Assam, Bangladesh, Bismarck Archipelago, Borneo, Cambodia, China North-Central, China South-Central, China Southeast, East Himalaya, Hainan, Japan, Jawa, Laos, Lesser Sunda Is., Malaya, Maluku, Myanmar, Nansei-shoto, Nepal, New Caledonia, New Guinea, New South Wales, Nicobar Is., Northern Territory, Philippines, Queensland, Solomon Is., South Australia, Sulawesi, Sumatera, Taiwan, Thailand, Vietnam, Wallis-Futuna Is., West Himalaya

Introduced into:

Alabama, Albania, Algeria, Andaman Is., Angola, Argentina Northeast, Argentina Northwest, Arkansas, Bahamas, Belize, Benin, Bermuda, Bolivia, Brazil Northeast, Brazil South, Brazil Southeast, Brazil West-Central, Bulgaria, California, Canary Is., Cape Verde, Caroline Is., Cayman Is., Central American Pac, Chad, Christmas I., Colombia, Comoros, Cook Is., Costa Rica, Cuba, Delaware, Dominican Republic, Ecuador, Egypt, El Salvador, Ethiopia, Fiji, Florida, Galápagos, Gambia, Georgia, Gilbert Is., Guinea-Bissau, Gulf of Guinea Is., Haiti, Honduras, Illinois, India, Iraq, Italy, Jamaica, Korea, Leeward Is., Libya, Line Is., Louisiana, Madeira, Marianas, Marshall Is., Maryland, Mauritania, Mauritius, Mexico Central, Mexico Southeast, Mississippi, Missouri, Morocco, Mozambique, Niger, Niue, North Carolina, Oklahoma, Oman, Pakistan, Panamá, Paraguay, Pennsylvania, Peru, Portugal, Puerto Rico, Rodrigues, Romania, Réunion, Samoa, Santa Cruz Is., Society Is., Socotra, Somalia, South Carolina, Spain, Sri Lanka, Tadzhikistan, Tennessee, Texas, Tibet, Tonga, Trinidad-Tobago, Tuamotu, Tunisia, Uzbekistan, Vanuatu, Venezuela, Virginia, West Virginia, Windward Is.

Citrus L. appears in other Kew resources:

Date Reference Identified As Barcode Type Status Has image?
Sands, M.J.S. [832], Papua New Guinea 29047.056 No
New Guinea 34478.000 No
Utteridge, T.M.A. [316], New Guinea 71256.000 No
70000.266 No

First published in Sp. Pl.: 782 (1753)

Accepted by

  • Govaerts, R. (1999). World Checklist of Seed Plants 3(1, 2a & 2b): 1-1532. MIM, Deurne.
  • Wu, Z. & Raven, P.H. (eds.) (2008). Flora of China 11: 1-622. Science Press (Beijing) & Missouri Botanical Garden Press (St. Louis).

Literature

Flora Zambesiaca

  • Gen. Pl. ed. 5: 341 (1754).
  • Sp. Pl. 2: 782 (1753)

Flora of Somalia

  • Flora Somalia, Vol 2, (1999) Author: by M. Thulin [updated by M. Thulin 2008]
  • Swingle, The botany of Citrus and its wild relatives, in Webber & Batchelor, The Citrus Industry 1: 129–474 (1943)
  • Tanaka, Species problems in Citrus, Revisio Aurantiacearum IX (1954)
  • Townsend in Flora of Iraq 4(1): 465–473 (1980).

Flora of Tropical East Africa

  • L., Gen. Pl., ed. 5: 341 (1754)
  • Sp. Pl.: 782 (1753)

  • Art and Illustrations in Digifolia

    Digital Image © Board of Trustees, RBG Kew

  • Flora Zambesiaca

    Flora Zambesiaca
    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Flora of Somalia

    Flora of Somalia
    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Flora of Tropical East Africa

    Flora of Tropical East Africa
    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0