Achyranthes aspera

Achyranthes aspera (common names: chaff-flower,^[1] prickly chaff flower,^[2] devil's horsewhip,^[3] Sanskrit: अपामार्ग apāmārga) is a species of plant in the family Amaranthaceae. It is distributed throughout the tropical world.^[4] It can be found in many places growing as an introduced species and a common weed.^[5] It is an invasive species in some areas, including many Pacific Islands environments.^[6]

Achyranthes aspera
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Order:	Caryophyllales
Family:	Amaranthaceae
Genus:	Achyranthes
Species:	A. aspera
Binomial name
Achyranthes aspera L.

Description

• Habit: a wild, perennial, erect herb.
• Stem: herbaceous but woody below, erect, branched, cylindrical, solid, angular, hairy, longitudinally striated, nodes and internodes are prominent, green but violet or pink at nodes.
• Leaves: ramal and cauline, simple, exstipulate, opposite decussate, petiolate, ovate or obovate, entire, acute or acuminate, hairy all over, unicostate reticulate.
• Inflorescence: a spike with reflexed flowers arranged on long peduncle.
• Flowers: bracteate, bracteolate, bracteoles two, shorter than perianth, dry, membranous and persistent, sessile, complete, hermaphrodite, actinomorphic, pentamerous, hypogynous, small, spinescent, green.
• Bracts: ovate, persistent, awned.
• Perianth: made up of 5 tepals, polyphyllous, imbricate or quincuncial, green, ovate to oblong, persistent.
• Androecium: made up of 10 stamens, out of which 5 are fertile and 5 are scale-like, fimbriated, sterile staminodes, both alternating with each other, fertile stamens are antiphyllous, monadelphous, filaments slightly fused at the base, dithecous, dorsifixed or versatile, introrse.
• Gynoecium: it is bicarpellary, syncarpous, superior, unilocular, ovule one, basal placentation, style single and filiform, stigma capitate.
• Fruits: oblong utricle
• Seeds: endospermic with curved embryo, 2 mm long, oblong black.
• Flowering and Fruiting time: September to April

Uses

Flowers and hirsute stem

The juice of this plant is a potent ingredient for a mixture of wall plaster, according to the Samarāṅgaṇa Sūtradhāra, which is a Sanskrit treatise dealing with Śilpaśāstra (Hindu precepts of art and construction).^[7]

Traditional medicine

A. aspera has been used in folk medicine, such as in Australia in the 19th century.^[8] The 1889 book The Useful Native Plants of Australia records that this plant was found "in all the tropical and sub-tropical regions of the old world. The herb is administered in India in cases of dropsy. The seeds are given in hydrophobia, and in cases of snake-bites, as well as in ophthalmia and cutaneous diseases. The flowering spikes, rubbed with a little sugar, are made into pills, and given internally to people bitten by mad dogs. The leaves, taken fresh and reduced to a pulp, are considered a good remedy when applied externally to the bites of scorpions. The ashes of the plant yield a considerable quantity of potash, which is used in washing clothes. The flowering spike has the reputation in India (Oude) of being a safeguard against scorpions, which it is believed to paralyse. (Drury.)"^[8]

Chemical constituents

Achyranthes aspera contains triterpenoid saponins which possess oleanolic acid as the aglycone. Ecdysterone, an insect moulting hormone, and long chain alcohols are also found in Achyranthes aspera.^[9]

Gallery

• 
  Opposite leaf arrangement and seeds attached to long peduncle. India
• 
  Tangle of long peduncles ("Devil's horsewhips") with sharp seeds makes walking through thickets difficult. India.
• 
  Pink flowers of Achyranthes aspera. Puntallana, La Palma, Canary Islands
• 
  Sharp seeds adherent to glove. Maui, Hawaii