Argemone mexicana
(Mexican poppy)

Preferred Scientific Name

• Argemone mexicana L.

Preferred Common Name

• Mexican poppy

Other Scientific Names

• Argemone alba Raf.
• Argemone leiocarpa Greene
• Argemone mucronata Dum.Cours. ex Steud.
• Argemone sexvalis Stokes
• Argemone spinosa Gaterau
• Argemone versicolor Salisb.
• Argemone vulgaris Spach
• Echtrus mexicanus (L.) Nieuwl.
• Echtrus trivialis Lour.
• Papaver mexicanum (L.) E.H.L.Krause

International Common Names

• English: Bermuda thistle; goatweed; Mexican pricklepoppy; Mexican pricklypoppy; Mexican thistle; prickly poppy; yellow thistle
• Spanish: adormidera espinosa; amapolas de campo; amapolo pinchuda; cardo amarillo; cardo blanco; cardo santo; chicalote
• French: argémone du Mexique; argemone mexicaine; chardon béni; chardon du pays; herb a femme; pavot du Mexique; pavot epineux; tache de l’oeil
• Portuguese: papoula-do-Mexico

Local Common Names

• Angola: papoula; papoula-do-México
• Argentina: cardo amarillo
• Bahamas: donkey thistle
• Bangladesh: Shialkata
• Benin: débilo; timtonyakorou
• Brazil: cardo-amarelo; cardo-santa; cardo-santa-maria; figo-do-inferno; morro do chapéu; papoula-de-espinho; papoula-espinhosa
• Burkina Faso: bara; baragoué; blatoumé; mérékagnien; souroukou taba; yra
• Chile: chicalote
• China: ji ying su
• Côte d'Ivoire: baragoué; blatoumé; mandé; mérékagnien; ouinigbe; souroukou taba; wenigbé
• Dominican Republic: Jamaica yellow thistle
• Ecuador: yellow prickly poppy
• Ethiopia: baro bangi; eshok tilian; korehare; kossalae; madafe
• Finland: fin naam
• Germany: Mexikanischer Stachelmohn
• Haiti: cardon fleurs jaunes; chadron à fleurs jaunes; chardon béni; pavot epineux
• India: agara; bharband; bharbhar; brahamadandi; bramandandu; kantakusama; katelisatyanasi; satyonasi
• Indonesia: celangkringan; droedjoe; druju; tjelangkringan
• Italy: fico infernale; papavero del Messico; papavero messicano
• Japan: Azami-Geshi
• Kenya: ekijembajembe; mkumajalaga
• Madagascar: fantsimboay
• Malaysia: chelang keringan
• Mali: bozobo; gninnidie; simsimji
• Mauritius: chardon du pays
• Mexico: chicalote; chichilotl
• Myanmar: kye-ja
• Netherlands: stekelpapaver
• Niger: Boginahi; Dàyí gííwáá; Hákóórín kádà; Káákí rúwàn Allàh; Kàankámárkà tà bíí kà; kamukamu; Kánkààmáá; Karanko; Kùùrár fataakee; Kwarakko; Kwaranko; Wagiri; Wasiri
• Nigeria: akunakun; Boginahi; Dàyí gííwáá; Hákóórín kádà; Káákí rúwàn Allàh; Kàankámárkà tà bíí kà; kamukamu; Kánkààmáá; Karanko; Kùùrár fataakee; Kwarakko; Kwaranko; mafowokanmomi; Wagiri; Wasiri
• Pakistan: kanderi; kundiari; sialkanta
• Paraguay: Cardo santo
• Philippines: diluariu; kachumba; kasubang-aso
• Puerto Rico: cardosanto
• Senegal: gapéye korkot
• South Africa: ikhakhakhakha; yellow-flowered Mexican poppy
• Tanzania: akatojo; rangiibili; rikararungu
• Vietnam: caf gai hoa vafng; gai cua; mufi cua
• Zimbabwe: umjelemani

EPPO code

• ARGME (Argemone mexicana)

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Papaverales
•                         Family: Papaveraceae
•                             Genus: Argemone
•                                 Species: Argemone mexicana

Argemone is from the Greek argena, meaning 'cataract of the eye', and was the name used in the first century AD by the classical authors Dioscorides (AD 40-90) and Pliny (AD 23-79) for some spiny poppies, the juice of which was supposedly a cure for cataract; mexicana combines Mexico with the Latin suffix ana, belonging to, suggesting the country of origin (Parsons and Cuthbertson, 1992).

Although Missouri Botanical Garden (2016) cites A. ochrouleuca as a synonym of A. mexicana, The Plant List (2016) and Otto and Verloove (2016) cite both as valid species. Of the names listed as synonyms, A. alba is reported as an illegitimate name (The Plant List, 2016). Many of the common names for this species result from the prickly stems and native range in Mexico.

A. mexicana is an annual herb, up to 150 cm tall with a slightly branched tap root. The stem is erect, branched, usually prickly, pale bluish-green and exudes an unpleasant-smelling yellow sap when cut. Leaves are alternate, without petioles, more or less sheathing the stem, up to 15 cm long, deeply lobed with irregularly toothed, spiny margins; greyish-white veins are conspicuous on the bluish-green upper surface of the leaves. Flowers are solitary, 2.5-4.5 cm in diameter, subtended by 1-2 leafy bracts; sepals 3, prickly; petals 4-6, yellow to pale orange, glabrous; stamens numerous. Fruit is a capsule, spiny, 2.5-5 cm long and 2 cm wide, with 4-6 valves opening at the tip to release numerous seeds. Seeds are brownish-black, nearly spherical, about 1 mm in diameter, covered in a fine network of veins, oily.

A. mexicana forma leiocarpa is a form found in West Africa which has few or no prickles on the stem, leaves and capsule (Lucas, 1962).

A. mexicana has been introduced accidentally (seed contaminant), as an ornamental or for its cultivation mainly for ethnobotanical purposes (Healy, 1961, APPEAR, 2016, PROSEA, 2016). Little is known about the history of its introduction and spread around the world. By 1814 it was the commonest weed of St Helena and was first recorded on Ascension in 1828. In New Zealand, it was accidentally introduced with imported wheat in the 1890s (Healy, 1961). The plant was introduced to Hawaii as an ornamental and was first recorded in 1934 (Wester, 1992). Tye (1999) reported that the plant was still relatively uncommon and suspected that it may become problematic in the future. In the Czech Republic, it was first reported occurring in the wild in 1965, but appears to have become extinct (Pysek et al., 2002).

Soil drainage

• free

Soil reaction

• acid
• alkaline
• neutral

Soil texture

• light
• medium

Special soil tolerances

• infertile

Natural Dispersal (Non-Biotic)

A. mexicana is reported as being dispersed by water and wind (PROTA, 2016).  

Vector Transmission (Biotic)

Birds might be dispersers as they have been seen eating the fruits (Barnés, 1946).

Accidental Introduction

The species has been reported as unintentionally introduced into the Indian Himalayas through trade exchange, including grain import (Chandra Sekar, 2012).

Intentional Introduction

A. mexicana has been used and introduced as an ornamental and for ethnobotanical purposes throughout its range (PROTA, 2016).

A. mexicana is a principal weed of beans and maize in Tanzania, cereals in Australia and India, cotton in Nicaragua, potatoes in India, tobacco in Argentina and Puerto Rico, and wheat in Pakistan (Holm et al., 1977). In Bangladesh, it grows in wheat, sugarcane, potato, pulses and tea fields (Islam et al., 2003). In Florida, USA, it is reported as a weed in tomato crops (Johnson, 1997) and Vaughan and Wiehe (1937) stated that it was frequent in cane fields in Mauritius. A. mexicana is one of the main weeds associated with common bean (Phaseolus vulgaris) in Nicaragua (Alemán, 2001). In the late 19th century the plant was not considered to be a bad weed in Kansas, USA (Hitchcock and Clothier, 1898). A. mexicana has an inhibitory effect on germination and seedling growth of vegetables (Hazarika and Sannigrahi, 2001) and weed residues may affect Bambara groundnut (Vigna subterranea) and sorghum (Sorghum bicolor) growth and development because of inhibitory effects of allelochemicals (Karikari et al. 2000).

In poultry, one ounce of seed causes symptoms (e.g. decreased egg production), and 2 ounces usually cause death (Everest et al., undated). Grazing animals generally avoid this weed but can be poisoned if it is consumed in hay or chaff. The species produces aflatoxins that are toxic to animals consuming contaminated crops and also could be found in milk, eggs and meat products (Alemayehu and Desalegn, 2016). The value of wool is decreased when contaminated by the prickly fruits of A. mexicana (Parsons and Cuthbertson, 1992). Harvesting by hand of low-growing field crops can be a painful experience in the presence A. mexicana and hired labour may expect to be paid a premium in these conditions.

Islam et al. (2003) has ascertained that the species reduces plant diversity, and Kumar and Rohatgi (1999) postulated that it decreases biodiversity in India. In Tanzania the plant is commonly found in the Lake Manyara National Park (Lyons, 2000). Alemayehu and Desalegn (2016) report a decrease in plant and animal diversity, and a disrupt in the ecosystems structure and function in Ethiopia. According to Namkeleja et al. (2014) the allelochemicals produced by A. mexicana can affect the germination, growth and chlorophyll content of plants in natural ecosystems.

A. mexicana has had a major impact on human health in the Indian subcontinent. Edible vegetable oil either accidentally contaminated with A. mexicana or intentionally adulterated by unscrupulous traders has resulted in a dropsy epidemic. Such an epidemic occurred in 1998 in Delhi (India) and also has been reported from Nepal (Jha et al., 2001; Sharma et al., 2002). Sharma et al. (1999) have provided a review of the clinical effects of adulterated oil and suggested preventive measures. An epidemic occurred in South Africa following the contamination of wheat flour (Sharma et al., 1999). In northern and central India, A. mexicana has been identified as an important allergen (Singh and Kumar, 2004). Subsistence farmers in the Ethiopian Highlands find this prickly plant difficult to manage in cereal fields.

• Invasive in its native range
• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Fast growing
• Has high reproductive potential
• Gregarious
• Has propagules that can remain viable for more than one year

• Ecosystem change/ habitat alteration
• Negatively impacts agriculture
• Negatively impacts human health
• Negatively impacts animal health
• Negatively impacts livelihoods
• Reduced native biodiversity
• Threat to/ loss of native species
• Damages animal/plant products

• Allelopathic
• Competition - monopolizing resources
• Hybridization
• Poisoning
• Rapid growth
• Produces spines, thorns or burrs

• Highly likely to be transported internationally accidentally
• Highly likely to be transported internationally deliberately
• Difficult to identify/detect as a commodity contaminant
• Difficult/costly to control

Economic Value

A. mexicana has shown antibiotic activity against Staphylococcus aureus, S. agalectiaei and Escherichia coli, with potential in the pharmaceutical industry (Alemayehu and Desalegn, 2016). It has been cultivated for its seed oil, which is used for soap production and for fuel (Hanelt and IPK, 2016).

Social Benefit

A. mexicana is used for religious purposes in Central America (Hanelt and IPK, 2016).

Extracts of the leaves, flowers and seeds of A. mexicana have been tested, mostly under laboratory conditions in India, against insect pests (Chitra et al., 1997), crop pathogens (Singh et al., 1993) and nematodes (Das and Sukul, 1988; Saxena and Tabassum, 2000; Shaukat et al., 2002). Aqueous extracts have been tested with success against Tropical Hen Louse, Lipeurus lawrensis tropicalis (Kumar et al. 2002). Studies suggest that the extracts from the roots can be used to prevent oviposition and act as ovicidal against Aedes aegypti (Warikoo and Kumar, 2014). Von Weizsäckerl (1995) reported that it is used in parts of India to prepare antifeedant sprays in the same way as is done with leaves of Azadirachta indica. Extracts of A. mexicana readily kill the snail Biomphalaria glabrata and thus have potential as a molluscide for the relatively cheap control of human schistosomiasis (Melendez and Capriles, 2002). Although control or suppression of these pests has been found, there is little evidence for the widespread practical exploitation of these findings.

Medicinal properties have been attributed to the sap and oil from the seed (Holm et al., 1977). In the Guianas the whole plant is used as an infusion against asthma. The root is taken in rum and cognac for stomach pain. Sap from the cut end of the stem is applied to cavities as a treatment for toothache. Children having difficulty with urination are given infusions of petals (DeFilipps et al., 2004). In India (Madhya Pradesh) it is reported to be a homeopathic drug (Oudhia et al., 1998). In West Africa it is used as a cosmetic, i.e. a washing milk (Rukangira, 2001).

In East Africa, the seeds are ground and put into beer or tea to increase their potency and cause drunkenness (Verdcourt and Trump, 1969). In India, A. mexicana seeds are added to mustard oil in very small quantities, to increase its pungency. However, recently in New Delhi, over 60 deaths have been attributed to adulteration of mustard oil with larger quantities of A. mexicana, as a means of reducing costs (The Indian Society of Weed Science, 1998).

Environmental services

Although the species has been reported as poisonous to animals, lemurs were seen eating the stems of the plants when other resources were scarce after a devastating cyclone in Madagascar (LaFleur and Gould, 2009). No detrimental health issues on the lemurs were reported by the authors.