''Mucuna urens'' is a species of large

liana A liana is a long- stemmed, woody vine that is rooted in the soil at ground level and uses trees, as well as other means of vertical support, to climb up to the canopy in search of direct sunlight. The word ''liana'' does not refer to a ta ...

from the family

Fabaceae The Fabaceae or Leguminosae,International Code of Nomenc ...

. The plant is native to tropical Central and South America, and has been introduced into the

Republic of the Congo The Republic of the Congo (french: République du Congo, ln, Republíki ya Kongó), also known as Congo-Brazzaville, the Congo Republic or simply either Congo or the Congo, is a country located in the western coast of Central Africa to the w ...

. Common names include horse-eye bean and ox-eye bean.

Taxonomy

The word ''mucuna'' is the

vernacular name A vernacular or vernacular language is in contrast with a "standard language". It refers to the language or dialect that is spoken by people that are inhabiting a particular country or region. The vernacular is typically the native language, n ...

for ''Mucuna urens'' in an indigenous language of Brazil, and in 1763 this word was chosen by the French botanist

Michel Adanson Michel Adanson (7 April 17273 August 1806) was an 18th-century French botanist and naturalist who traveled to Senegal to study flora and fauna. He proposed a "natural system" of taxonomy distinct from the binomial system forwarded by Linnaeus. ...

in his ''Familles naturelles des plantes'' to be the

generic epithet Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat ...

for this genus of

legume A legume () is a plant in the family Fabaceae (or Leguminosae), or the fruit or seed of such a plant. When used as a dry grain, the seed is also called a pulse. Legumes are grown agriculturally, primarily for human consumption, for livestock f ...

s, although ''M. urens'' was itself known as ''Dolichos urens'' until being transferred to ''Mucuna'' many years later.

Description

''Mucuna urens'' is a large, vigorous, much-branched, twining

that climbs into the tree

canopy Canopy may refer to: Plants * Canopy (biology), aboveground portion of plant community or crop (including forests) * Canopy (grape), aboveground portion of grapes Religion and ceremonies * Baldachin or canopy of state, typically placed over an a ...

. The stems are thick and soft, and bear alternate, trifoliate leaves with petioles up to long. The leaflets are ovate or elliptical, and up to long; the lateral leaflets are somewhat oblique, and all leaflets have rounded bases and

apiculate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

tips. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

s grow laterally or in the axils of the leaves and are pendulous

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

s with peduncles up to a metre long, with the flowering part near the tip. The calyx has a long tube and the

petal Petals are modified Leaf, leaves that surround the reproductive parts of flowers. They are often advertising coloration, brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''c ...

s are thick, waxy and yellowish. The

standard Standard may refer to: Symbols * Colours, standards and guidons, kinds of military signs * Standard (emblem), a type of a large symbol or emblem used for identification Norms, conventions or requirements * Standard (metrology), an object th ...

is slightly longer than the

wings A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is expresse ...

and

keel The keel is the bottom-most longitudinal structural element on a vessel. On some sailboats, it may have a hydrodynamic and counterbalancing purpose, as well. As the laying down of the keel is the initial step in the construction of a ship, in Br ...

. The flowers are followed by transversely-ridged, oblong pods about bearing orange-brown bristly stinging hairs; the pods have a suture underneath and two longitudinal, undulating wings. The one to four seeds are rounded, almost surrounded by hilum and or more in diameter.

Distribution and habitat

This liana is native to the West Indies, Central and South America, its range extending from Panama to Peru, Ecuador, Bolivia and Brazil. It grows in forests and woodland at altitudes of up to .

Uses

''Mucuna urens'' is used in

traditional medicine Traditional medicine (also known as indigenous medicine or folk medicine) comprises medical aspects of traditional knowledge that developed over generations within the folk beliefs of various societies, including indigenous peoples, before the ...

. A

tincture A tincture is typically an extract of plant or animal material dissolved in ethanol (ethyl alcohol). Solvent concentrations of 25–60% are common, but may run as high as 90%.Groot Handboek Geneeskrachtige Planten by Geert Verhelst In chemistr ...

made from the powdered bean macerated in alcohol is a soothing remedy used against

hemorrhoid Hemorrhoids (or haemorrhoids), also known as piles, are vascular structures in the anal canal. In their normal state, they are cushions that help with stool control. They become a disease when swollen or inflamed; the unqualified term ''hemo ...

s, especially those inclined to bleed. The stinging hairs that grow on the pods can be taken internally against intestinal worms, which are expelled alive. These hairs are irritating to the skin and cause intense itching, with reddening and the formation of tiny pustules, soon after contact; the active chemical is the

proteolytic enzyme A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the for ...

mucunain The proteolytic enzyme mucunain is a protein in the tissues of certain legumes of the genus ''Mucuna'', especially velvet bean ('' Mucuna pruriens''). In these species the mucunain is found in stiff hairs, or trichomes, covering the seed A ...

. Potable water can be obtained from the fleshy stems. Fibres from the stem are used to make strong

rope A rope is a group of yarns, plies, fibres, or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than similarly ...

, and the seeds are used to make

bead A bead is a small, decorative object that is formed in a variety of shapes and sizes of a material such as stone, bone, shell, glass, plastic, wood, or pearl and with a small hole for threading or stringing. Beads range in size from under ...

s and ornaments, as well as being used as

famine food A famine food or poverty food is any inexpensive or readily available food used to nourish people in times of hunger and starvation, whether caused by extreme poverty, such as during economic depression or war, or by natural disasters such as ...

. An extract of the seeds given to male

guinea pig The guinea pig or domestic guinea pig (''Cavia porcellus''), also known as the cavy or domestic cavy (), is a species of rodent belonging to the genus ''Cavia'' in the family Caviidae. Breeders tend to use the word ''cavy'' to describe the ani ...

s at low dosages was found to cause the degeneration of sperm, raising the possibility that the plant could be used as a male anti-fertility agent.

References

External links

* * {{Taxonbar, from=Q15474001 urens