Nasturtium microphyllum (Boenn. ex Rchb.) Rchb.

Nasturtium species are annual or perennial herbs, aquatic or semi terrestrial, usually glabrous, sometimes pubescent, not scapose. Rootstocks rhizomatous. Stem procumbent, prostrate, decumbent or erect, leafy, simple or sparsely branched. Leaves cauline, not in rosulate, oblanceolate to oblong in outline, margin pinnately compound to simple with 5-9 leaflets, ovate-lanceolate to elliptic, leaflet margins dentate to entire, lateral leaflets shortly petiolulate or sessile, terminal leaflet long petiolulate, apex obtuse to subemarginate, petiole wide and auriculate near the base. Inflorescence raceme corymbs, many flowered, considerably elongated in fruit, ebracteate. Flowers bisexual, cream white, yellow, rarely pink, pedicel erect, divaricate, stout, slender, ascending, glabrous or pubescent above, sepals 4, linear lanceolate-oblong, inner lateral pair base saccate or not, petals 4, obovate to spathulate, much longer than sepals, base attenuate, margins entire, apex obtuse, claw undifferentiated. Stamens 6, tetradynamous, filaments white, not dilated near the base, anthers linear-oblong, nectar glands 2, lateral, annular or semiannular. Ovary superior, bicarpellary, ovules 20-50. Fruit siliqua, dehiscent, linear, flattened narrow oblong, terete, erect or slightly curved, valves obscurely veined, glabrous or slightly torulose, replum rounded, septum complete, style obsolete or short, stigma capitate, entire. Seeds uniseriate or biseriate, brown, plump, oblong-ovoid, not winged, minutely to coarsely reticulate, not mucilaginous when soaked, cotyledons accumbent.

Nasturtium species flowers are complete, bisexual, i.e., with functional male (androecium) and female (gynoecium), including stamens, carpels and ovary. Pollination is entomophilous i.e., by insects, or cleistogamy i.e., by self or allogamy i.e., by cross pollination. Flowering/Fruiting: April—July.

Seeds may be dispersed by autochory i.e., self dispersal, anemochory i.e., wind dispersal, zoochory i.e., dispersal by birds or animals, anthropochory i.e., dispersal by humans.

Herbs, aquatic or semi terrestrial, usually glabrous, sometimes sparsely pubescent, about 15-75 cm tall, not scapose. Rootstocks rhizomatous. Stem procumbent, prostrate, decumbent or erect, leafy, simple or sparsely branched. Leaves cauline, not in rosulate, oblanceolate to oblong in outline about 6-20 x 2-6 cm across, base auriculate, pinnately compound with 5-9 leaflets, ovate-lanceolate to elliptic, about 1.5-3.5 x 0.5-2 cm across, base cuneate, leaflet margins dentate to entire, lateral leaflets shortly petiolulate or sessile, terminal leaflet long petiolulate, apex obtuse to subemarginate, petiole wide and not winged near the base. Inflorescence raceme corymbs, many flowered, considerably elongated in fruit, ebracteate. Flowers bisexual, cream white, yellow, rarely pink, pedicel erect or slightly curved, divaricate, stout, slender, ascending, glabrous or pubescent above, about 8-12 mm long, about 12-22 mm long in fruit, sepals 4, linear lanceolate-oblong, greenish white, inner lateral pair base saccate or not, about 2.5-4 x 1 mm across, petals 4, obovate to spathulate, much longer than sepals, base attenuate, margins entire, apex obtuse, about 4.5-6 x 1.5-3 mm across, claw undifferentiated. Stamens 6, tetradynamous, filaments white, not dilated near the base, about 2.5-3.5 mm long, anthers linear-oblong, about 1 mm long, nectar glands 2, lateral, annular or semiannular. Ovary superior, bicarpellary, ovules 30-40. Fruit siliqua, dehiscent, linear, flattened narrow oblong or subcylindrical, about 15-25 x 1-1.3 mm across, terete, erect or slightly curved, valves membranous, glabrous or slightly torulose, replum rounded, septum complete, style about 1-1.5 mm long, stigma capitate, entire. Seeds uniseriate, reddish brown, plump, oblong-ovoid, about 1-1.2 x 0.7 mm across, not winged, minutely to coarsely reticulate with about 100-150 areolae, not mucilaginous when soaked, cotyledons accumbent.

Nasturtium species are susceptible to various insect pests, virus and moulds.

Marshy places, lake margins and wet meadows.

Not evaluated (IUCN).

Leaves are used as garnishing the salads, also used as medicine.