in W. Aiton and W. T. Aiton, Hortus Kew. 4: 110. 1812
North America, n Mexico, Central America, Europe, Asia, n Africa, introduced also in South America, tropical and s Africa, Australia, nearly worldwide.
Species 5 (4 in the flora).
There has been considerable disagreement as to whether Nasturtium should be maintained as a distinct genus or be united with Rorippa. Molecular data and a critical evaluation of morphology (I. A. Al-Shehbaz and R. A. Price 1998) clearly show that Nasturtium is much more closely related to Cardamine than it is to Rorippa, and that the two genera should not be united.
Plants of Nasturtium floridanum, N. microphyllum, and N. officinale typically produce compound leaves when submerged in shallow waters or when their branches are emergent. When submerged in deep waters, all three produce simple leaves, and, in that case, it is impossible to distinguish them. The hybrid between N. officinale and N. microphyllum, N. ×sterilis Airy Shaw, is uncommon in North America, having been reported from Connecticut, Idaho, Michigan, and New Hampshire (P. S. Green 1962), and is far more common in Europe, where it has recently been studied thoroughly (W. Bleeker et al. 1999 and references therein). Nasturtium africanum Braun-Blanquet is known from Morocco in northwestern Africa.
|1||Seeds biseriate, coarsely reticulate, with 25-50(-60) areolae on each side; fruits (1.8-) 2-2.5(-3) mm wide.||Nasturtium officinale|
|1||Seeds uniseriate, minutely to moderately reticulate, with (75-)100-500 areolae on each side; fruits 0.8-1.2(-1.8) mm wide||> 2|
|2||Emergent leaves: petiolar bases non-auriculate; blades 3(-5)-foliolate; seeds light or yellowish brown; Florida.||Nasturtium floridanum|
|2||Emergent leaves: petiolar bases often minutely auriculate; blades (3-)5-17-foliolate; seeds reddish brown; not Florida||> 3|
|3||Leaflet margins entire or repand; seeds with (75-)100-150(-175) areolae on each side; filaments 2.5-3.5 mm; petals 4.5-6 mm; petioles and rachises not winged.||Nasturtium microphyllum|
|3||Leaflet margins coarsely dentate or, rarely, sinuate-repand; seeds with 300-450 areolae on each side; filaments 5-7 mm; petals 6-8 mm; petioles and rachises narrowly winged.||Nasturtium gambelii|
|Author||Ihsan A. Al-Shehbaz +|
|Authority||W. T. Aiton in W. Aiton and W. T. Aiton +|
|Common name||Watercress +|
|Distribution||North America +, n Mexico +, Central America +, Europe +, Asia +, n Africa +, introduced also in South America +, tropical and s Africa +, Australia + and nearly worldwide. +|
|Etymology||Latin nasus, nose, and tortus, distortion, alluding to pungency of plants +|
|Illustrator||Yevonn Wilson-Ramsey +|
|Publication title||in W. Aiton and W. T. Aiton, Hortus Kew. +|
|Publication year||1812 +|
|Reference||green1962a +, rollins1978a +, shehbaz1988a + and shehbaz1998a +|
|Source xml||https://firstname.lastname@example.org/aafc-mbb/fna-data-curation.git/src/f6b125a955440c0872999024f038d74684f65921/coarse grained fna xml/V7/V7 760.xml +|
|Taxon family||Brassicaceae +|
|Taxon name||Nasturtium +|
|Taxon parent||Brassicaceae tribe Cardamineae +|
|Taxon rank||genus +|
|Volume||Volume 7 +|