The Encyclopedia of Psychoactive Plants: Ethnopharmacology and Its Applications

Rhynchosia pyramidalis (Lam.) Urban


Bird’s Eyes




Leguminosae: Papilionideae (Legume Family); Subfamily Fabodeae

Forms and Subspecies


The genus consists of some three hundred species that are found in the tropical and subtropical regions of both hemispheres (Schultes and Hofmann 1980, 338*).



Dolicholus phaseoloides Sw.

Rhynchosia phaseoloides (Sw.) DC.

Folk Names


Äh mo’ ak’ (Lacandon,“ara parrot vine”), antipusi, atecuixtle, atecuxtli, bejuco culebra, bird’s eyes, casanpulgas, chanate pusi, cha’pak’ (Mayan), colorín chiquito, colorincito, colorines (cf. Erythrina americana), coralito, frijol de chintlatlahua, frijolillo, guarecitas, gun-ma-muy-tio-ña (Chinantec), krebsaugenbohne, liucai-nofal (Chontal), negritos, ojitos de picho (Spanish, “little eyes of the dove”), ojo de cangrejo (Spanish, “crab’s eye”), ojo de chanate (Mexico, “eye of the thrush [Cassidix mexicanus]”), ojo de culebra (Spanish, “eye of the snake”), ojo de pajarito (Spanish, “eye of the little bird”), ojo de zanate (Mexico, “eye of the thrush [Cassidix mexicanus]”), pega palo, peonía, perico, peyote (see Lophophora williamsii), pipilzíntli, piule, pulguitas, puren-sapicho, saltipús, senecuilche (see Heimia salicifolia), shasham wupu’är (Pima), sinicuiche, xenecuilche



Plants and Fungi Known in Mexico as Piule

(from Martínez 1987, 757*; Ott 1993, 419*; Santesson 1938; supplemented)




“I was still living in the unformed world when the hermaphroditic animals rose in the heavy atmosphere of the depths of the dark waters—when fingers, fins, and wings were still a single thing, when eyes without heads swam around like mollusks between steers with human faces and snakes with dog’s paws.”






(1979, 122*)




The Aztecs may have used the striking seeds of this plant for ritual purposes (Schultes and Hofmann 1980, 340*). The red-black seeds, which are known by the name piule (Santesson 1938), were or are used ritually in the village of San Pedro Nexapa, on the slopes of Popocatepetl (Mexico) (Wasson and Wasson 1957, 306 f.). In Mexico, the name piule has been used as a catchall term for psycho-active plants since the twentieth century (Martínez 1987, 757*; cf. Psilocybe mexicanaTurbina corymbosa). The word piule may have been derived from the Nahuatl peyotl (= Lophophora williamsii). Accordingly, piuleros are those people who use a psychoactive substance (piule) to divine and/or heal (Santesson 1937a, 1937b). Some species, e.g., Rhynchosia longeracemosa Mart. et Gal., are now also known by the name peyote (Schultes 1966, 296*).



This climber is found throughout the tropical and warm regions of Mexico and on many islands of the Caribbean (Cuba) (von Reis and Lipp 1982, 139*). It usually grows at the edge of forests and in clearings. It is frequently found in fallow milpas (slash-and-burn gardens).



The seeds are best pregerminated in a mixture of soil and moss. The seedlings must be planted in topsoil and watered well as soon as the seeds have opened and the young shoots have become visible (Grubber 1991, 56*). The plant requires a moist, warm climate and in northern zones can thus be grown only as a houseplant.



The vine, which can grow to a length of several meters, has the typical leaves of the Legume Family, in which three leaves sit upon each stalk. The greenish flowers are arranged in long racemes. The bean-shaped seedpods are constricted between the two small, red-black, almost spherical hard seeds (4 to 6 mm long).

The kidney-shaped seeds of the closely related Rhynchosia longeracemosa are “mottled light- and dark-brown” (Schultes and Hofmann 1992, 55*).

Rhynchosia pyramidalis is often confused with Abrus precatorius L. (jequirity, rosary pea), which is widely feared as a poisonous plant. It too produces red-black seeds, although they are somewhat larger (6 to 7 mm long). Jequirity can be recognized by its smaller, pinnate leaves. The seeds of Abrus precatorius contain abrin, a lectin mixture that is unstable when heated and one of the most potent of all known toxins, along with several alkaloids (Ghosal and Dutta 1971; Nwodo 1991; Nwodo and Alumanah 1991; Roth et al. 1994, 83 f.*). In Mexico, the seeds of Abrus precatorius are known as colorines (see Erythrina spp.). They are associated with the mescal bean cult (see Sophora secundiflora); ashes from the leaves are used as a coca additive (see Erythroxylum coca).

Psychoactive Material


—Seeds (semina rhynchosiae phaseoloides, bird’s eyes, colorines)


Preparation and Dosage


In entheogenic rituals in the high valleys of Mexico, twelve untreated seeds were ingested with six pairs of Psilocybe aztecorum per person (Wasson and Wasson 1957, 306).

Ritual Use


To date, the only description that is available pertains to the ritual use of the seeds in connection with the ingestion of mushrooms. The ingestion of the seeds is presumably more symbolic in meaning, for the red-black seeds represent bodiless, free-floating eyes, a symbol of psychedelic and prophetic vision.

The Zapotec of Miahuatlan are said to have used the seeds of the closely related species Rhynchosia minima (L.) DC. [syn. Dolicholus minimus] in magical rituals (Díaz 1979, 87*).



The small, durable seeds are made into amulets and chains (cf. Erythrina americanaErythrina spp., Sophora secundiflora).

Wall paintings at Teopantitla (near Teotihuacán) allegedly show the seeds falling out of the hand of the rain god Tláloc (D. McKenna 1995, 102*). The red-black coloration is said to be an indication of the seeds’ hallucinogenic use (Schultes 1970c; Schultes and Hofmann 1980, 340*).

Medicinal Use


The seeds are regarded as a narcotic and poison in Mexican folk medicine (Jiu 1996, 254*). The Yucatec Maya use the root along with other herbs to produce a medicine to treat pellagra286 (Pullido

S. and Serralta P. 1993, 37*). The Pima of northern Mexico grind the seeds on a mortar and strew the powder into the eyes of those who are suffering from the “evil eye” (Pennington 1973, 223*).

In the Dominican Republic, the stalks are used to prepare an aphrodisiac drink (Díaz 1979, 87*).



The chemistry of the constituents has not yet been clarified. Reports about the alkaloids are contradictory (Santesson 1937a). The seeds apparently contain alkaloids similar to those in Sophora secundifloraand Erythrina spp. (D. McKenna 1995, 102*). The root may possibly contain niacin or nicotine amide, for it is used in the Yucatán as a folk medicine to treat pellagra (maidism). Whether the flavonol rhynchosin (Adinarayana et al. 1980) occurs in the plant is unknown.



In Mexico, it is commonly believed that the seeds cause “imbecility” or “madness” (Díaz 1979, 87*; Jiu 1996, 254*). There are as yet no reports of actual psychoactive effects. An extract of the seeds is said to have curare-like activity (Schultes and Hofmann 1980, 340*).

Commercial Forms and Regulations


The seeds are sometimes available through the international seed trade. Mexican Indians sometimes sell necklaces with beads of Rhynchosia seeds.


The bird’s eyes vine (Rhynchosia) in bloom. (Photographed in Palenque, Mexico)



The seeds of Rhynchosia resemble those of the poisonous jequirity (Abrus precatorius L.) to the smallest detail.



An Indian necklace made from the seeds of Abrus precatorius. Because the toxic alkaloids are supposedly absorbed through the skin, many tourists fear wearing such chains. Experience, however, has shown that the wearing of such a necklace will not result in any effects. Jequirity seeds contain the alkaloid abrin, which is lethal at a dosage of 0.01 mg/kg. This notwithstanding, particularly courageous Plains Indians appear to have used the seeds as “red medicine” for vision quests.


“Just one single seed [of jequirity, Abrus precatorius]—which must however be chewed thoroughly before swallowing—can produce lethal effects in humans. Cattle and goats are more resistant, but 60– 120 g of seeds can also kill a horse.


A case of poisoning proceeds in the following sequence: First, stomach pains become noticeable, the urge to vomit appears, the patient falls into a coma, and the circulation collapses so that the patient dies. . . . In some tropical countries, the unripe seeds are used to murder a person; they are formed into sharp needles that are then stabbed into the victim. Because the toxin can directly enter the bloodstream in this manner, it is usually lethal. . . . In some places, the seeds are used to produce decorative objects. They are used, for example, to make necklaces, chains, and also rosaries.”






(1983, 28*)




See also the entries for Erythrina spp. and Sophora secundiflora.


Adinarayana, Dama, Duvvuru Gunasekar, Otto Seligmann, and Hildebert Wagner. 1980. Rhynchosin, a new 5-deoxyflavonol from Rhynchosia beddomeiPhytochemistry 19:483–84.


Ghosal, S., and S. K. Dutta. 1971. Alkaloids of Abrus precatoriusPhytochemistry 10:195–98.


Grear, J. W. 1978. A revision of the New World species of Rhynchosia (Leguminosae-Fabodeae). Memoirs of the New York Botanical Garden 31 suppl. (1): 1–168.


Nwodo, O. F. C. 1991. Studies on Abrus precatorius seeds. I: Uterotonic activity of seed oil. Journal of Ethnopharmacology 31 (3): 391–94.


Nwodo, O. F. C., and E. O. Alumanah. 1991. Studies on Abrus precatorius seeds. II: Antidiarrhoeal activity. Journal of Ethnopharmacology 31 (3): 395–98.


Ristic, S., and A. Thomas. 1962. Zur Kenntnis von Rhynchosia pyramidalis (Pega Palo). Archiv für Pharmakologie 295:510.


Santesson, C. G. 1937a. Notiz über piule, eine mexikanische Rauschdroge. Etnologiska Studier (Göteborg) 4:1–11.


———. 1937b. Piule, eine mexikanische Rauschdroge. Archiv für Pharmazie: 532–37.


———. 1938. Noch eine mexikanische “Piule”-Droge: Semina Rynchosiae phaseoloidis DC. [sic!]. Etnologiska Studier 6:179–83.


Wasson, R. Gordon, and Valentina P. Wasson. 1957. Mushrooms, Russia, and history. New York: Pantheon Books.