in C. F. Ecklon and K. L. P. Zeyher, Enum. Pl. Afric. Austral. 2: 279. 1836
Asia, Africa, introduced widely.
Species 5 (3 in the flora).
In Citrullus the rind (hypanthium/pericarp) may be firm and tough or thin and fragile; it may be durable (persisting intact after maturity) or not. The mesocarp can be fleshy or dry and it varies in color from red or pink to orange, light yellowish orange, yellow, greenish, or whitish.
Citrullus lanatus is commonly established in the flora area as a waif but rarely, if ever, persists more than one season. Citrullus caffer is a poorly documented transient and C. colocynthis apparently grows as a weed in crop fields.
The five species of Citrullus are C. lanatus, the domesticated watermelon; C. caffer (C. lanatus var. citroides), the preserving melon or citron; C. colocynthis, the bitter apple; and C. ecirrhosus Cogniaux and C. rehmii DeWinter, wild species endemic to desert regions of Namibia. Citrullus caffer, C. lanatus, and C. rehmii are monoecious annuals; C. colocynthis and C. ecirrhosus are perennials. All are native to dry habitats of northern Africa (C. colocynthis) or southern Africa (C. caffer, C. ecirrhosus, C. lanatus, and C. rehmii), and all are cross-compatible with each other.
The monotypic Praecitrullus Pangalo [P. fistulosus (Stocks) Pangalo, Indian round gourd, apple gourd, Indian baby pumpkin], a monoecious annual from Afghanistan, India, and Pakistan, was segregated from Citrullus and has proved to be more closely related to Benincasa (F. Dane and P. Lang 2004; A. Levi and C. E. Thomas 2005; Levi et al. 2010).
Discovery of 5000-year-old Citrullus lanatus seeds in Libya (K. Wasylikowa and M. Van der Veen 2004) indicates that its domestication might have occurred in northern Africa. Remains also have been found in tombs and temples in Egypt (ca. 1330 bce) and Sudan (1500 bce). Seeds of C. colocynthis appear in early Egyptian, Libyan, and near-eastern sites, and it was probably used prior to its domestication (F. Dane and P. Lang 2004; Dane and J. Liu 2007). Watermelons are mentioned in European herbals from the 1500s and by 1625 were widely planted as a minor crop in European gardens. They arrived early in North America with European colonists, appearing in Florida by 1567 and in Massachusetts by 1629.
Aquino Assis, J. G. de et al. 2000. Implications of the introgression between Citrullus colocynthis and C. lanatus characters in the taxonomy, evolutionary dynamics and breeding of watermelon. Pl. Genet. Resources Newslett. 121: 15–19.
Jarret, R. L. and M. Newman. 2000. Phylogenetic relationships among species of Citrullus and the placement of C. rehmii De Winter as determined by internal transcribed spacer (ITS) sequence heterogeneity. Genet. Resources Crop Evol. 47: 215–222.
|1||Plants perennial; stems pustulate-scabrous to pustulate-hispid; tendrils usually unbranched, rarely 2-branched; pepos 4–7(–10) cm diam.||Citrullus colocynthis|
|1||Plants annual; stems villous; tendrils 2–3-branched; pepos 12–35+ cm diam||> 2|
|2||Leaf blades ovate to lanceolate-ovate or ovate-triangular, mostly 8–20 cm; pepos globose to oblong-ellipsoid, 12–35+ cm diam., rind tough, not durable, mesocarp juicy, red to orange, yellow, or greenish, sweet.||Citrullus lanatus|
|2||Leaf blades ovate, 3–8 cm; pepos globose to globose-ovoid, 15–25 cm diam., rind tough, durable, mesocarp dry, whitish, bitter.||Citrullus caffer|
|Author||Guy L. Nesom +|
|Authority||Schrader in C. F. Ecklon and K. L. P. Zeyher +|
|Basionyms||Anguria + and Colocynthis +|
|Distribution||Asia +, Africa + and Introduced widely. +|
|Etymology||Generic name Citrus and Latin - ellus, diminutive, alluding to supposed resemblance of fruits +|
|Illustrator||Yevonn Wilson-Ramsey +|
|Publication title||in C. F. Ecklon and K. L. P. Zeyher, Enum. Pl. Afric. Austral. +|
|Publication year||1836 +|
|Reference||aquino2000a +, dane2004a +, f2004a +, f2007a +, fursa1972a +, fursa1981a +, jarret2000a + and levi2005a +|
|Source xml||https://firstname.lastname@example.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse grained fna xml/V6/V6 66.xml +|
|Special status||Introduced +|
|Taxon family||Cucurbitaceae +|
|Taxon name||Citrullus +|
|Taxon parent||Cucurbitaceae +|
|Taxon rank||genus +|
|Volume||Volume 6 +|