Asystasia gangetica
(chinese violet)

Pictures

Picture	Title	Caption	Copyright
Title Flowering shoot Caption Asystasia gangetica flowering shoot. Copyright John Terry	Flowering shoot	Asystasia gangetica flowering shoot.	John Terry

Identity

Preferred Scientific Name

• Asystasia gangetica (L.) T. Anderson, 1860

Preferred Common Name

• chinese violet

Other Scientific Names

• Asystasia coromandeliana Nees
• Justicia gangetica L.

International Common Names

• English: creeping foxglove; ganges primrose; philippine violet
• Spanish: asistasia; coromandel
• French: herbe le rail; herbe piment; herbe pistache
• Chinese: kuan ye shi wan cuo

Local Common Names

• Malaysia: rumput nyonya
• Mauritius: herbe pistache
• South Africa: asystasia; creeping foxglove
• Thailand: baya; yaya

EPPO code

• ASYCO (Asystasia gangetica)

Summary of Invasiveness

A. gangetica is a fast growing perennial plant which is included on various lists of invasive plants, including for Cuba, Puerto Rico and Hawaii. In Australia, A. gangetica subsp. micrantha is on the National Environmental Alert List (Ismail and Shukor, 1998) while in Florida it is considered a noxious weed. The ability of A. gangetica to tolerate a remarkable range of habitats including disturbed areas, cultivated areas, and semi-waterlogged areas, as well as climates means that this species has the potential to spread much further than it has to date. Additionally, this species can form a dense ground cover, presumably competing with native species (Varnham, 2006).

Taxonomic Tree

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Scrophulariales
•                         Family: Acanthaceae
•                             Genus: Asystasia
•                                 Species: Asystasia gangetica

Notes on Taxonomy and Nomenclature

The family Acanthaceae includes about 4000 species widespread in both New and Old World Tropics. This family includes a range of morphological diversity, habitats, and biogeographic patterns. The genus Asystasia includes about 40 species of paleotropical origin (Acevedo-Rodríguez, 2005). For A. gangetica two subspecies have been identified: A. gangetica subsp. gangetica and A. gangetica subsp. micrantha. The original range of the subspecies is unclear, but it is likely that A. gangetica subsp. gangetica was limited to Asia, and A. gangetica subsp. micrantha was limited to Africa (Ismail and Shukor, 1998).

Description

Perennial herbs, erect, decumbent, or clambering; 1-3 m in length. Stems quadrangular. Leaves opposite; blades simple, with numerous linear cystoliths on the upper surface, the secondary veins conspicuous; stipules absent. Flowers bisexual, zygomorphic, arranged in spikes on axillary branches. Calyx green, 5-7 mm long, the sepals lanceolate; corolla asymmetrically funnel-shaped, light yellow or pale violet, 2.3-5 cm long, with glandular hairs on the outer surface; stamens and pistil inserted on the floral tube. Capsules ellipsoid or club-shaped, 2-2.5 cm long, light brown when ripe, densely covered with glandular hairs; seeds 2-4 light brown, with irregular margins, lenticular (Acevedo-Rodríguez, 2005).

Distribution

The species A. gangetica is native to tropical Malaysia, India, and Africa, but has been introduced into tropical areas in North, Central and South America, Hawaii, West Indies, and Australia as an ornamental herb and eventually escapes into natural and disturbed areas.

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

History of Introduction and Spread

A. gangetica was introduced as an ornamental plant into the Caribbean islands of Martinique, Guadalupe, St. Vincent and Barbados as early as 1898. Ignaz Urban, in the Symbolae Antillanae reported this species as a “culta et quasi spontanea” for these islands. This species was reported for Puerto Rico for the first time by Liogier and Martorell in 1982 (although collected in 1963) as “cultivated and escaped in moist districts” and for the Virgin Islands by Acevedo-Rodríguez in 1996 as “in gardens or escaped in disturbed areas”. In Puerto Rico, this species is known from the northern half of the island where it is considered as “quite common” (Acevedo-Rodríguez, 2005). A. gangetica was also introduced in Hawaii and in French Polynesia where it has been classified as a “potential problematic species” and by 2002 this species was included in the Global Compendium of Weeds (http://www.hear.org/gcw/). In Australia since 1998 the subspecies A. gangetica micrantha is on the National Environmental Alert List (Ismail and Shukor, 1998) and must be reported when found. In Florida it has been listed as an invasive and noxious weed since 1999 (USDA-NRCS, 2012).

Risk of Introduction

The risk of introduction of A. gangetica is high, mainly because this species is still used as an ornamental herb in many countries. The species is dispersed by seeds and rhizomes. The seeds are dispersed from explosive capsules, but long-distance dispersal is effected by man. The risk of introduction of rhizome material as a contaminant of soil and compost remains high in those countries where the plant is well established.

Habitat

A. gangetica is a rapidly growing perennial, shrubby herb which grows to 1 m height and can be found along roadsides, altered natural areas, cultivated areas and riverbanks as well as in semi-waterlogged areas. In Hawaii, Pacific Islands, Puerto Rico and the Virgin Islands this species has been recorded in cultivated areas, urban areas, and disturbed habitats (PIER, 2012).

Habitat List

Biology and Ecology

Genetics

Recent work with A. gangetica in Singapore, showed that for this species the gametic chromosome number is n=13. The somatic chromosome number for the species is therefore 2n=26, and the chromosomes generally form ring bivalents (Pandit et al., 2006).

Physiology and Phenology

A. gangetica has been collected in flower and fruit throughout the year in the West Indies (Acevedo-Rodríguez, 2005).

Longevity

A. gangetica is a rapidly growing perennial.

Climate

Means of Movement and Dispersal

A. gangetica is dispersed by seeds and by rhizomes. Seeds are dispersed from explosive capsules.

Impact Summary

Environmental Impact

A. gangetica has been identified as a weed which can smother native plants where it has been introduced. This is possibly due to the fact that this species is a facultative climber and forms dense colonies. Further studies are needed to identify the mechanisms.

Threatened Species

Risk and Impact Factors

• 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
• Tolerant of shade
• Benefits from human association (i.e. it is a human commensal)
• Long lived
• Fast growing
• Reproduces asexually

• Ecosystem change/ habitat alteration

• Highly likely to be transported internationally deliberately

Uses

In Africa (South Africa, Nigeria, Kenya, and Tanzania) the leaves are eaten as a vegetable (e.g. Mepba et al., 2007) and used as an herbal remedy in traditional medicine. The leaves are used in Nigeria for the treatment of asthma (Akah et al., 2003). It is also used as an ornamental plant in countries of the Neotropics.

Similarities to Other Species/Conditions

Asystasia resembles the genus Dyschoriste but can be differentiated by their inflorescences. Dyschoriste has flowers arranged in cymose fascicles or singly at the axils while those of Asystasia are arranged in distal spikes or racemes (Durkee, 1986).

Prevention and Control

Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.

Work with A. gangetica in Hawaii suggests that this species is probably sensitive to hormone-type herbicides (Motooka et al., 2003).

Gaps in Knowledge/Research Needs

More information is needed on reproductive biology of this species, and on environmental requirements for germination and establishment of seedlings and juvenile plants. Studies to evaluate the impact of the plant on native species in areas where it has been introduced, and recommendations for management and control in natural areas invaded by this species, are also needed.

References

Acevedo-Rodríguez P, 1996. Flora of St. John, U.S. Virgin Islands. Memoirs of the New York Botanical Garden, 78:1-581

Acevedo-Rodríguez P, 2005. Vines and climbing plants of Puerto Rico and the Virgin Islands. Contributions from the United States National Herbarium, 51:483 pp

Acevedo-Rodríguez P, Strong MT, 2012. Catalogue of the Seed Plants of the West Indies. Smithsonian Contributions to Botany, 98:1192 pp. Washington DC, USA: Smithsonian Institution. http://botany.si.edu/Antilles/WestIndies/catalog.htm

Adams CD, 1972. Flowering Plants of Jamaica. University of the West Indies, 267

Akah PA, Ezike AC, Nwafor SV, Okoli CO, Enwerem NM, 2003. Evaluation of the anti-asthmatic property of Asystasia gangetica leaf extracts. Journal of Ethnopharmacology, 89(1):25-36

Daniel TF, 1997. Catalog of the Acanthaceae of Belize with taxonomic and phytogeographic notes. Contributions of the University of Michigan Herbarium, 21:161-174

Durkee LH, 1986. Family Acanthaceae. Fieldiana, 18:1-87. [Flora Costaricensis.]

Flora of China Editorial Committee, 2012. Flora of China Web. Cambridge, USA: Harvard University Herbaria. http://flora.huh.harvard.edu/china/

Forzza RC, Leitman PM, Costa AF, Carvalho Jr AA, et al. , 2012. List of species of the Flora of Brazil (Lista de espécies Flora do Brasil). Rio de Janeiro, Brazil: Rio de Janeiro Botanic Garden. http://floradobrasil.jbrj.gov.br/2012/

Funk V, Hollowell T, Berry P, Kelloff C, Alexander SN, 2007. Checklist of the plants of the Guiana Shield (Venezuela: Amazonas, Bolivar, Delta Amacuro; Guyana, Surinam, French Guiana). Contributions from the United States National Herbarium, 584 pp

Gibbs Russell GE, Welman WG, Reitief E, Immelman KL, Germishuizen G, Pienaar BJ, Wyk Mvan, Nicholas A, 1987. List of species of southern African plants. Memoirs of the Botanical Survey of South Africa, 2(1 & 2):1-152 & 1-270

González-Torres LR, Rankin R, Palmarola A (eds), 2012. Invasive plants of Cuba. (Plantas Invasoras en Cuba.) Bissea: Boletin sobre Conservacion de Plantad del Jardin Botanico Nacional, 6:1-140

Hedberg I, Edwards S, eds, 1989. Flora of Ethiopia, Volume 3 : Pittosporaceae to Araliaceae. National Herbarium, Addis Ababa University, Ethiopia and Department of Systematic Botany, Uppsala University Sweden. 670 pp

Idárraga-Piedrahita A, Ortiz RDC, Callejas Posada R, Merello M, 2011. Flora of Antioquia. (Flora de Antioquia.) Catálogo de las Plantas Vasculares, vol. 2. Listado de las Plantas Vasculares del Departamento de Antioquia:939 pp

Idu M, Onyibe HI, 2007. Medicinal plants of Edo State, Nigeria. Research Journal of Medicinal Plant, 1(2):32-41. http://academicjournals.net/2/c4p.php?id=2&theme=2&jid=rjmp

Ismail S, Shukor A, 1998. Effects of water stress, shading and clipping on growth and development of Asystasia gangetica. Plant Protection Quarterly, 13:140-142

ISSG, 2012. Global Invasive Species Database (GISD). Global Invasive Species Database (GISD). Auckland, New Zealand: University of Auckland . http://www.issg.org/database

Liogier HA, Martorell LF, 1982. Flora of Puerto Rico and adjacent islands: a systematic synopsis. Río Piedras, Puerto Rico: Editorial de la Universidad de Puerto Rico

Long RW, Lakela OK, 1971. A Flora of Tropical Florida: A Manual of the Seed Plants and Ferns of Southern Peninsular Florida. Coral Cables, USA: University of Miami Press

Mepba HD, Eboh L, Banigo DEB, 2007. Effects of processing treatments on the nutritive composition and consumer acceptance of some Nigerian edible leafy vegetables. African Journal of Food, Agriculture, Nutrition and Development, 7(1):1-18. http://www.ajfand.net/Issue-XII-files/PDFs/MEPBA_1855.pdf

Mori S, Buck B, Gracie C, Tulig M, 2008. Plants and Lichens of Saba. New York, USA: New York Botanical Garden. http://sweetgum.nybg.org/saba/

Motooka P, Ching L, Nagai G, 2002. Herbicidal weed control methods for pastures and natural areas of Hawaii. Weed Control Nov. 2002 - WC-8. p1-35. http://www2.ctahr.hawaii.edu/oc/freepubs/pdf/WC-8.pdf

ORSTOM, 1988. List of vascular plants of Gabon

Pandit MK, Tan HTW, Bisht MS, 2006. Polyploidy in invasive plant species of Singapore. Botanical Journal of the Linnean Society, 151(3):395-403. http://www.blackwell-synergy.com/doi/abs/10.1111/j.1095-8339.2006.00515.x

PIER, 2012. Pacific Islands Ecosystems at Risk. Honolulu, USA: HEAR, University of Hawaii. http://www.hear.org/pier/index.html

Smithsonian Institution, 2012. Flora of the West Indies. Flora of the West Indies., USA: Smithsonian Institution. http://botany.si.edu/antilles/westindies/

Urban I, 1898. Symbolae Antillanae Seu Fundamenta Florae Indiae Occidentalis, vol. 1. Berolini, Fratres Borntraeger. http://www.biodiversitylibrary.org/item/23192#page/7/mode/1up

US Fish and Wildlife Service, 2014. U.S. Fish and Wildlife Service species assessment and listing priority assignment form: Hylaeus assimulans. In: U.S. Fish and Wildlife Service species assessment and listing priority assignment form: Hylaeus assimulans : US Fish and Wildlife Service.33 pp. http://ecos.fws.gov/docs/candidate/assessments/2014/r1/I0GQ_I01.pdf

US Fish and Wildlife Service, 2014. U.S. Fish and Wildlife Service species assessment and listing priority assignment form: Hylaeus facilis. In: U.S. Fish and Wildlife Service species assessment and listing priority assignment form: Hylaeus facilis : US Fish and Wildlife Service.32 pp. http://ecos.fws.gov/docs/candidate/assessments/2014/r1/I0GY_I01.pdf

US Fish and Wildlife Service, 2014. U.S. Fish and Wildlife Service species assessment and listing priority assignment form: Hylaeus hilaris. In: U.S. Fish and Wildlife Service species assessment and listing priority assignment form: Hylaeus hilaris : US Fish and Wildlife Service.31 pp. http://ecos.fws.gov/docs/candidate/assessments/2014/r1/I0HT_I01.pdf

USDA-ARS, 2012. Germplasm Resources Information Network (GRIN). Online Database. Beltsville, Maryland, USA: National Germplasm Resources Laboratory. https://npgsweb.ars-grin.gov/gringlobal/taxon/taxonomysearch.aspx

USDA-NRCS, 2012. The PLANTS Database. Baton Rouge, USA: National Plant Data Center. http://plants.usda.gov/

Varnham K, 2006. Non-native species in UK Overseas Territories: a review. Peterborough, UK. [JNCC Report 372.] http://www.jncc.gov.uk/page-3660

Wagner WL, Herbst DR, Sohmer SH, 1990. Manual of Flowering Plants of Hawaii. Bernice Pauahi Bishop Museum Special Publication 83. Honolulu, Hawaii, USA: University of Hawaii

Links to Websites

Contributors

16/07/12 Original text by:

Julissa Rojas-Sandoval, Department of Botany-Smithsonian NMNH, Washington DC, USA

Pedro Acevedo-Rodríguez, Department of Botany-Smithsonian NMNH, Washington DC, USA

Distribution Maps