pronounced: ar-GY-ree-uh ner-VOH-suh
Argyreia is derived from the Greek αργυρος (argyros), silver, referring to the colour of the underside of the leaf; nervosa is from the Latin nervosus, sinewy, energetic, nervous; Convoluvus is also Latin, convolvere, to twine around; and speciosus is Latin, showy, beautiful, handsome.
The plant photographed self-seeded itself in a Picnic Bay garden. The species is known to grow on Cape Cleveland and Alligator Creek, so this plant probably owes its presence here to a visiting bird. It is a very vigorous vine indeed, as can be gathered from the mile-a-minute common name. The plant has been present in Queensland for over 90 years, probably as a garden escapee. An extinct native species, Argyreia souteri, described by Bailey at Johnstone River in 1890, may have actually been A. nervosa. The capsules are buoyant in water, and it may have spread from other areas round the Pacific before white settlement of Australia.
This native of the Indian subcontinent is a perennial vine that can grow to a height of 5 m or more. It flourishes in direct sunlight in hot, humid climates. The stem is slender, woody, branching and twining. The cordate leaves are large and leathery, silvery on the underside because of fine hairs. Clusters of pink-purple trumpet-shaped flowers, about 5 cm in diameter, are followed by dry capsules, each containing 4 – 6 seeds. When the fruits are ripe, they dehisce, and open into a rose shape. In many parts of the world the plant will not produce fruit until the second year of planting.
There are two main varieties of the plant, var. speciosa and var. nervosa. The former is used in Ayurvedic medicine. The root is used as an aphrodisiac tonic. A poultice of the leaves is applied as a stimulant and a rubifacient. The leaves are soaked for 7 days in Asparagus racemosus juice and taken with ghee to improve intellect, strengthen the body, and prevent the effects of aging. This preparation is also said to assist in treating bronchitis, nervousness, syphilis, diabetes, tuberculosis and arthritis.
It is some forms of var. vervosa that have a high LSA alkaloid content in the seeds. LSA (Lysergic Acid Amide) is closely related to LSD, and like the latter can produce psychedelic and hallucinogenic effects. The legal situation with regard to the seeds varies from country to country. In Australia, it is illegal to import or to export the seeds, but not to grow or possess them, although this last is a grey area. Seeds treated with sulphur dust to make them unpalatable may be legally sold or possessed in Australia, but the laws about consuming the seeds vary from state to state. Consumption of anything containing LSA is prohibited under state legislation in most Australian states.
