Lepidium didymum, the lesser swine-cress, is a species of flowering plant in the family Brassicaceae.
Lepidium didymum is an annual or biennial herb[1] with decumbent or ascending and glabrous green stems, up to long, radiating from a central position. The leaves are pinnate and alternate and can reach a length of 5cm (02inches). It blooms between July and September. The flowers are inconspicuous, the four white petals very short or absent, with 2 (rarely 4),[2] stamens and the fruits consist of two rounded valves, notched at the apex, with a very short style between.[3] [4] They are also wrinkled and contain orange or reddish brown seeds, that are 1–5 mm long.[4]
It was first described and published by the Swedish botanist Carl Linnaeus in 'Mant. Pl.' (Mantissa Plantarum) on page 92 in 1767.[5]
The specific epithet didymum, refers to the Greek word δίδυμα for 'twin' or 'in pairs',[6] referring to the seed capsule.
Lepidium didymum is of uncertain origin,[1] but is often cited as native to South America,[3] [2] mainly Argentina, Bolivia, Brazil, Chile, Paraguay, Peru, Uruguay and Venezuela.[7] It has been introduced elsewhere as a weed of cultivation. It has naturalised across the globe, from Africa, Europe, Asia, Australasia, North America and South America.[7] In Britain, it had been recorded from the wild by 1778,[1] chiefly in England and the south of Ireland,[8] growing on cultivated and waste ground, in gardens and lawns, by paths and roadsides.
The leaves of this plant are edible, and have a salty, cress or mustard flavour.[9] [10]
. Stace, C. A.. 2010. New Flora of the British Isles. Third. Cambridge University Press. Cambridge, U.K.. 9780521707725.