Thunbergia grandiflora
(Bengal trumpet)

Identity

Preferred Scientific Name

• Thunbergia grandiflora Roxb.

Preferred Common Name

• Bengal trumpet

Other Scientific Names

• Flemingia grandiflora Rottler
• Thunbergia adenophora W.W. Sm.
• Thunbergia chinensis Merr.
• Thunbergia cordifolia Nees
• Thunbergia lacei Gamble

International Common Names

• English: Bengal clock vine; Bengal trumpet vine; blue thunbergia; blue trumpet vine; large thunbergia; sky vine; skyflower vine; trumpet vine
• Spanish: brisa de la mañana; corona de rey; faurestina; fausto; pompeya; tumbergia azul
• French: liane de chine; liane mauve

Local Common Names

• Australia: blue sky vine; blue trumpet
• Dominican Republic: ristra de ajo
• Micronesia, Federated states of: iolen pengkal (Pohnpei)
• Palau: bung el etiu
• Samoa: palulu

Summary of Invasiveness

T. grandiflora is a woody vine included in the Global Compendium of Weeds and it is listed as a very aggressive weed impacting tropical and subtropical ecosystems (Randall, 2012). This species has been repeatedly introduced as an ornamental plant in many countries around the world, but it has become a serious environmental problem when it has escaped from cultivated areas and rapidly colonized natural habitats (ISSG, 2012). The rapid colonization of new habitat by this vine is mainly due to its capability to reproduce sexually by seeds and vegetatively by cuttings, fragments of stems and roots (USDA-NRCS, 2012). Once established, T. grandiflora completely smothers native vegetation by killing host-trees, out-competing understory plants, and negatively affecting the germination and establishment of seedlings of native species (Starr et al., 2003). Currently, T. grandiflora is classified as a “noxious weed” in Australia (Queensland Department of Primary Industries and Fisheries, 2007), and as an invasive species in Central America, the West Indies, Africa, and numerous islands in the Pacific including Hawaii, Fiji, French Polynesia, Palau, and Samoa (see distribution table for details; Acevedo-Rodríguez and Strong, 2012; ISSG, 2012; PIER, 2012).

Taxonomic Tree

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

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. Many species within the family are commonly used as ornamentals including species in the genera Justicia, Peristrophe, Ruellia, and Thunbergia (Liogier, 1988; Stevens, 2012). The genus Thunbergia includes about 90 species of herbaceous or woody vines, and less often shrubs of paleotropical origin (Stevens, 2012). The species T. alata, T.fragrans, and T. laurifolia have also been described as invasive species in tropical and subtropical regions of the world (PIER, 2012; Randall, 2012).

Description

Perennial, woody vine, 10-20 m in length. Stems are cylindrical, up to 2.5 cm in diameter, striate, puberulous; cross section of the stem with the pith hollow and the xylem tissue with wide rays. Leaves are opposite; blades 15-26 × 13-30 cm, ovate or broadly ovate, chartaceous, the apex acute or acuminate, the base cordiform, the margins lobate-dentate, ciliate; upper surface is dark green, shiny, puberulous, with slightly prominent venation; lower surface is light green, dull, glabrous or puberulous, with prominent venation; petioles 6-12 cm long. Flowers are arranged in axillary cymes; pedicels robust, cylindrical, 4-6 cm long; bracts light green, ovate, approximately 4 cm long, covering the calyx and the corolla tube. The calyx is green with the form of a ring, 4-5 mm long; corolla lilac-blue or white, with 5 lobes, the tube 6-7 cm long, light yellow inside, narrow at the base, the limb 6-7 cm in diameter. Fruits are capsules, approximately 3 cm long, subglobose at the base, the upper half in the form of a beak, explosively dehiscent in two halves (Acevedo-Rodríguez, 2005).

Plant Type

Distribution

T. grandiflora is native to India, parts of China and south Asia, but widely cultivated and naturalized in tropical and subtropical regions. Currently it can be found in Mexico, Central America, the West Indies, South America, tropical Africa, Southeastern Asia, Australia, and the Pacific Islands (USDA-ARS, 2012; PIER, 2012).

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

T. grandiflora was probably introduced as an ornamental in the Caribbean Region late in the nineteenth century. It appears in an 1892 herbarium collection made by A. Duss on Guadeloupe Island (Smithsonian Herbarium Collection). Later, Ignaz Urban in his book Symbolae Antillanae reported this species as “cultivated in gardens and escaped” for the islands of Cuba, Guadeloupe, Dominica, Martinique, and St. Vincent (Urban, 1901). T. grandiflora was also reported as commonly planted in gardens by N.L. Britton in Bermuda in 1918 (Britton, 1918) and in Puerto Rico and Virgin Islands in 1925 (Britton and Wilson, 1925). During the 1990s this species has been collected in Puerto Rico from naturalized individuals from widespread localities (Acevedo-Rodríguez, 2005). In Hawaii, T. grandiflora was first collected in 1937 on O'ahu and it is now spreading along hiking trails or margins of urban areas, at least on Kaua'i, O'ahu, Maui, and Hawaii (Wagner et al., 1999; Starr et al., 2003).

Risk of Introduction

T. grandiflora has been intentionally planted as an ornamental and it has escaped from gardens and spread rapidly into natural forests, climbing into the canopy of mature trees and forming dense monoculture stands (Starr, 2003; ISSG, 2012). In addition, it has a natural great dispersal capability by seeds, fragments of stems and roots (PIER, 2012). In consequence, the probability of invasion of this species remains high.

Habitat

T. grandiflora can be found growing in moist areas from sea level to middle elevations. It is especially common in disturbed areas, urban forests near human settlements, riparian forests, forest gaps, forest edges and along roadsides (ISGG, 2012; PIER, 2012). In Australia, this species has been reported growing in areas from sea level to 750 metres in riparian areas, rainforest margins, roadsides, disturbed sites and old gardens (Queensland Department of Primary Industries and Fisheries, 2007). In Hawaii, T. grandiflora grows in lowland moist areas, disturbed forests, and urban areas (Starr et al., 2003).

Habitat List

Biology and Ecology

Genetics

The chromosome number estimated for T. grandiflora is 2n=28 (Daniel and Chuang, 1989). 

Reproductive Biology

For species in the genus Thunbergia, flowers are bisexual, zygomorphic, axillary, usually solitary, with long pedicels and a pair of foliaceous bracts covering the lower portion of the corolla (Acevedo-Rodríguez, 2005). In the case of T. grandiflora, pollinators are unknown, but based on floral traits, this species could be considered entomophilous.  

Physiology and Phenology

In Puerto Rico, T. grandiflora has been recorded flowering throughout the year and fruiting sporadically from May to July (Acevedo-Rodríguez, 2005). In Australia, it produces flowers and fruits throughout the year (Queensland Department of Primary Industries and Fisheries, 2007). 

Environmental Requirements

T. grandiflora grows best on fertile soils with good drainage in areas with warm temperatures at low elevation (i.e., from sea level to about 750 metres; Queensland Department of Primary Industries and Fisheries, 2007). This species does not tolerate shaded conditions and climbs over trees and shrubs looking for sunny areas in the canopy of the forests.

Climate

Rainfall

Rainfall Regime

Soil Tolerances

Soil drainage

• free

Soil reaction

• alkaline
• neutral

Soil texture

• heavy
• light
• medium

Special soil tolerances

• shallow

Notes on Natural Enemies

Thunbergia species are susceptible to spider mites, whiteflies, and scale insects (Brickell and Zuk, 1997).

Means of Movement and Dispersal

T. grandiflora reproduces sexually by seeds and vegetatively by stem fragments, tubers, and roots (Starr et al., 2003; ISSG, 2012; PIER, 2012). Seeds are catapulted several metres when ripe pods open and they can also be dispersed by rivers, streams and on waterways after rain storms (Queensland Department of Primary Industries and Fisheries, 2007). T. grandiflora also spreads by underground tubers and roots that easily re-spread producing new plants. Fragments of stems and roots may be dispersed to new locations by humans, livestock, vehicles, and/or floodwaters. Tubers and roots can also be spread by the movement of soil (Starr et al., 2003; BioNET-EAFRINET, 2011; ISSG, 2012; PIER, 2012).

Pathway Causes

Pathway Vectors

Impact Summary

Environmental Impact

T. grandiflora has an extensive tuberous root system, which can weigh up to 70 kg and can damage river banks, paths, fences and building foundations (Motooka et al., 2003). This fast-growing vine forms dense colonies that engulf native vegetation, climbing high into forest canopies and shading-out vegetation in the understory of native forests. For example, in some areas in Australia this species can cover 100% of the vegetation (Queensland Department of Primary Industries and Fisheries, 2007). It also impacts negatively on the germination and establishment of seedlings of native plants and the weight of the stems can kill host- trees (BioNET-EAFRINET, 2011; ISSG, 2012). In Australia, T. grandiflora is a serious environmental problem. It is affecting agricultural lands and it is a serious danger to the survival of small remnants of the threatened lowland tropical rainforest in the areas of Queensland that have been fragmented by agricultural and urban development (Queensland Department of Primary Industries and Fisheries, 2007).

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
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Pioneering in disturbed areas
• Highly mobile locally
• Long lived
• Fast growing
• Has high reproductive potential
• Reproduces asexually

• Ecosystem change/ habitat alteration
• Host damage
• Infrastructure damage
• Monoculture formation
• Reduced native biodiversity
• Threat to/ loss of native species

• Competition - monopolizing resources
• Competition - shading
• Competition - smothering
• Competition - strangling
• Rapid growth
• Rooting

• Highly likely to be transported internationally deliberately

Uses

T. grandiflora is an economically important species widely cultivated as an ornamental and as a hedge plant in tropical and subtropical regions (Starr et al., 2003). This species is still sold in nurseries and is commonly planted to cover fences and walls in gardens in warm climates. In addition, T. grandiflora is used as a medicinal plant in traditional medicine in Asia and Africa. In Tropical Africa (Tanzania and Uganda), it has been used as a source of green manure and for fuelwood (Bio-NET-EAFRINET, 2011).

Uses List

General

• Ornamental

Materials

• Green manure

Medicinal, pharmaceutical

• Traditional/folklore

Ornamental

• Propagation material

Similarities to Other Species/Conditions

T. laurifolia is very similar in appearance and habit to T. grandiflora. It has similar flowers; leaves are of similar size but with a different shape and texture, being oval and narrowing to a pointed tip (Queensland Department of Agriculture and Fisheries, 2007).

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.

Physical/Mechanical Control

Small plants as well as small infestations should be removed manually. All plant segments and roots have to be removed in order to avoid re-sprouts. Large mature plants have extensive underground root systems, thus specialized machinery is necessary. In addition to mechanical control, the use of this species as an ornamental should be discouraged, especially in areas near natural forests (Queensland Department of Agriculture and Fisheries, 2007). 

Chemical Control

Spraying or painting cut stumps with herbicides such as glyphosate is an effective control method (Bio-NET-EAFRINET, 2011). Imazapyr is very effective in killing thunbergia, and does not drastically affect surrounding vegetation (Queensland Department of Agriculture and Fisheries, 2007). Good application technique should result in few non-target plants being killed. 

Control recommendations suggest that chemical control of T. grandiflora should include mechanical cutting followed by applications of herbicides such as glyphosate, triclopyr or 2.4-D to the cut stems. Follow-up treatments are recommended until control is completed (Motooka et al., 2003; Queensland Department of Agriculture and Fisheries, 2007).

References

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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

Balick MJ, Nee M, Atha DE, 2000. Checklist of the vascular plants of Belize. Memoirs of the New York Botanical Garden, 85:1-246

BioNET-EAFRINET (The East African Network for Taxonomy), 2011. Thunbergia grandiflora (Blue Thunbergia). Keys and Fact Sheets for Invasive Plants. http://keys.lucidcentral.org/keys/v3/eafrinet/weeds/key/weeds/Media/Html/Thunbergia_grandiflora_%28Blue_Thunbergia%29.htm

Brickell C, Zuk JD, 1997. The American Horticultural Society A-Z Encyclopedia of Garden Plants. New York, USA: Dorling Kindersley Publishing, 1104 pp

Britton NL, 1918. Flora of Bermuda. New York, USA: Charles Scribner's Sons. 585 pp

Britton NL, Wilson P, 1925. Botany of Porto Rico and the Virgin Islands. Scientific Survey of Porto Rico & Virgin Islands, Volume 6

Broome R, Sabir K, Carrington S, 2007. Plants of the Eastern Caribbean. Online database. Barbados: University of the West Indies. http://ecflora.cavehill.uwi.edu/index.html

Chacón E, Saborío G, 2012. Red Interamericana de Información de Especies Invasoras, Costa Rica ([English title not available]). San José, Costa Rica: Asociación para la Conservación y el Estudio de la Biodiversidad. http://invasoras.acebio.org

Chong KY, Tan HTW, Corlett RT, 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species. Singapore: Raffles Museum of Biodiversity Research, National University of Singapore, 273 pp. http://lkcnhm.nus.edu.sg/nus/pdf/PUBLICATION/LKCNH%20Museum%20Books/LKCNHM%20Books/flora_of_singapore_tc.pdf

Correa A, Galdames MDC, Stapf MNS, 2004. Catalogue of vascular plants of Panama (Catalogo de Plantas Vasculares de Panama.), Panama: Smithsonian Tropical Research Institute, 599 pp

Daniel TF, 2001. Catalog of Acanthaceae in El Salvador. Contributions from the University of Michigan Herbarium, 23:115-137

Daniel TF, 2005. Catalog of Honduran Acanthaceae with taxonomic and phytogeographic notes. Contributions from the University of Michigan Herbarium, 24:51-108

Daniel TF, Chuang TI, 1989. Chromosome numbers of some cultivated Acanthaceae. Baileya, 23:86-93

Dawson W, Mndolwa AS, Burslem DFRP, Hulme PE, 2008. Assessing the risks of plant invasions arising from collections in tropical botanical gardens. Biodiversity and Conservation, 17(8):1979-1995. http://www.springerlink.com/content/7653v67635014234/?p=8183fb2c7dcf468ba31ce33f67c6bec3&pi=11

Englberger K, 2001. Piper auritum. Pest Alert, 19. Kolonia, Pohnpei, Federated States of Micronesia: SPC, Plant Protection Micronesia

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

Florence J, Chevillotte H, Ollier C, Meyer JY, 2011. [English title not available]. (Base de données botaniques Nadeaud de l'Herbier de la Polynésie Française (PAP).) . http://www.herbier-tahiti.pf

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

Gibson DN, 1974. Acathanceae. Fieldiana, Botany, 24(10/4):328-462. [Flora of Guatemala.]

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

Graveson R, 2012. Plants of Saint Lucia. http://www.saintlucianplants.com

Hancock IR, Henderson CP, 1988. Flora of the Solomon Islands. Research Bulletin No. 7. Honiara, Solomon Islands: Dodo Creek Research Station

Herrera K, Lorence DH, Flynn T, Balick MJ, 2010. Checklist of the vascular plants of Pohnpei with local names and uses. Lawai, Hawaii, USA: National Tropical Botanical Garden, 146 pp

Idárraga-Piedrahita A, Ortiz RDC, Callejas Posada R, Merello M, 2011. Flora de Antioquia. Catálogo de las Plantas Vasculares, vol. 2. Listado de las Plantas Vasculares del Departamento de Antioquia ([English title not available]). 939 pp

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

Jørgensen PM, León-Yànez S, 1999. Catalogue of the vascular plants of Ecuador. Monogr. Syst. Bot. Missouri Bot. Gard, 75. i-viii, 1-1182

Liogier AH, 1988. Flora of Puerto Rico and Adjacent Islands: A Systematic Synopsis. Rio Piedras, Puerto Rico: Editorial de la Universidad de Puerto Rico

MacKee HS, 1994. Catalogue of introduced and cultivated plants in New Caledonia. (Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie.) Paris, France: Muséum National d'Histoire Naturelle, unpaginated

Mori SA, Buck WR, Gracie CA, Tulig M, 2007. Plants and Lichens of Saba. [Virtual Herbarium of The New York Botanical Garden.] http://sweetgum.nybg.org/saba/

Motooka P, Castro L, Nelson D, Nagai G, Ching L, 2003. Weeds of Hawaii's Pastures and Natural Areas; an identification and management guide. Manoa, Hawaii, USA: College of Tropical Agriculture and Human Resources, University of Hawaii

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

Queensland Department of Primary Industries and Fisheries, 2007. Thunbergia species fact sheet. Special edition of Environmental Weeds of Australia for Biosecurity Queensland., Australia: The University of Queensland and Department of Primary Industries and Fisheries. http://www.daff.qld.gov.au/documents/Biosecurity_EnvironmentalPests/IPA-Thunbergia-PP23.pdf

Randall RP, 2012. A global compendium of weeds, 2. Western Australia: Department of Agriculture and Food Western Australia, 1124 pp

Smith AC, 1981. Flora Vitiensis nova: a new flora of Fiji (spermatophytes only). Volume 2. 1981, 818 pp.; many pl. (8 col.)

Space JC, Flynn T, 2002. Report to the Government of Samoa on invasive plant species of environmental concern. Hawaii, USA: USDA Forest Service, Institute of Pacific Islands Forestry, 80 pp

Space JC, Lorence DH, LaRosa AM, 2009. Report to the Republic of Palau: 2008 update on Invasive Plant Species. Hilo, Hawaii, USA: USDA Forest Service, 227. http://www.sprep.org/att/irc/ecopies/countries/palau/48.pdf

Starr F, Starr K, Loope L, 2003. Thunbergia grandiflora in Hawaii. Report from the U.S. Geological Survey, Biological Resources Division, Haleakala Field Station, Hawaii. Thunbergia grandiflora in Hawaii. Report from the U.S. Geological Survey, Biological Resources Division, Haleakala Field Station, Hawaii. http://www.hear.org/starr/hiplants/reports/pdf/thunbergia_grandiflora.pdf

Stevens PF, 2012. Angiosperm Phylogeny Website. http://www.mobot.org/MOBOT/research/APweb/

Thaman RR, Fosberg FR, Manner HI, Hassall DC, 1994. The flora of Nauru. Atoll Research Bulletin, 392:1-223

Tropical Biology Association, 2010. Invasive plants in the Usambara Mountains, Tanzania. Invasive plants in the Usambara Mountains, Tanzania. http://www.tropical-biology.org/research/dip/species.htm

Urban I, 1901. Symbolae Antillanae. Volumen II. Lipsiae, Germany: Fratres Borntraeger, 860 pp

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/

Vieria Silva VRMDa, 2002. [English title not available]. (Flora da Madeira Plantas Vasculares Naturalizadas No Arquipélago da Madeira.) Boletim do Museu Municipal do Funchal (História Natural) supplement, 8:5-281

Wagner WL, Herbst DR, Sohmer SH, 1999. Manual of the flowering plants of Hawaii. Revised edition. Honolulu, Hawaii, USA: University of Hawaii Press/Bishop Museum Press, 1919 pp

Witt, A., Luke, Q., 2017. Guide to the naturalized and invasive plants of Eastern Africa, [ed. by Witt, A., Luke, Q.]. Wallingford, UK: CABI.vi + 601 pp. http://www.cabi.org/cabebooks/ebook/20173158959 doi:10.1079/9781786392145.0000

Wu TL, 2001. Check List of Hong Kong Plants. Hong Kong Herbarium and the South China Institute of Botany. Agriculture, Fisheries and Conservation Department Bulletin 1 (revised):384 pp. http://www.hkflora.com/v2/flora/plant_check_list.php

Wunderlin RP, Hansen BF, 2008. Atlas of Florida Vascular Plants. Tampa, Florida, USA: University of South Florida. http://www.plantatlas.usf.edu/

Zuloaga FO, Morrone O, Belgrano MJ, 2008. Catálogo de las Plantas Vasculares del Cono Sur (Argentina, Sur de Brasil, Chile, Paraguay y Uruguay). Volumen 1: Pteridophyta, Gymnospermae y Monocotyledoneae (Catalogue of the vascular plants of the southern cone (Argentina, southern Brazil, Chile, Paraguay and Uruguay). Volume 1: Pteridophyta, Gymnospermae and Monocotyledoneae) [ed. by Zuloaga FO, Morrone O, Belgrano MJ]. St. Louis, USA: Missouri Botanical Garden Press, 983 pp

Distribution References

Acevedo-Rodríguez P, 2005. Contributions from the United States National Herbarium, Washington, USA: Department of Systematic Biology - Botany, National Museum of Natural History, Smithsonian Institution. 51, 483 pp.

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

Anon, 1999. Catalogue of the vascular plants of Ecuador. [ed. by Jørgensen P M, León-Yànez S]. Missouri, USA: Missouri Botanical Garden. viii + 1182 pp.

Balick MJ, Nee M, Atha DE, 2000. Checklist of the vascular plants of Belize. In: Memoirs of the New York Botanical Garden, 85 1-246.

Broome R, Sabir K, Carrington S, 2007. Plants of the Eastern Caribbean. Online database., Barbados: University of the West Indies. http://ecflora.cavehill.uwi.edu/index.htm

CABI, Undated. Compendium record. Wallingford, UK: CABI

CABI, Undated a. CABI Compendium: Status inferred from regional distribution. Wallingford, UK: CABI

CABI, Undated b. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI

Chacón E, Saborío G, 2012. [English title not available]. (Red Interamericana de Información de Especies Invasoras, Costa Rica)., San José, Costa Rica: Asociación para la Conservación y el Estudio de la Biodiversidad. http://invasoras.acebio.org

Chong KY, Tan HTW, Corlett RT, 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species., Singapore, Raffles Museum of Biodiversity Research, National University of Singapore. 273 pp. http://lkcnhm.nus.edu.sg/nus/pdf/PUBLICATION/LKCNH%20Museum%20Books/LKCNHM%20Books/flora_of_singapore_tc.pdf

Correa A, Galdames MDC, Stapf MNS, 2004. Catalogue of vascular plants of Panama. (Catalogo de Plantas Vasculares de Panama)., Panama: Smithsonian Tropical Research Institute. 599 pp.

Daniel T F, 2001. Catalog of Acanthaceae in El Salvador. Contributions from the University of Michigan Herbarium. 115-137.

Daniel T F, 2005. Catalog of Honduran Acanthaceae with taxonomic and phytogeographic notes. Contributions from the University of Michigan Herbarium. 51-108.

Dawson W, Mndolwa A S, Burslem D F R P, Hulme P E, 2008. Assessing the risks of plant invasions arising from collections in tropical botanical gardens. Biodiversity and Conservation. 17 (8), 1979-1995. http://www.springerlink.com/content/7653v67635014234/?p=8183fb2c7dcf468ba31ce33f67c6bec3&pi=11 DOI:10.1007/s10531-008-9345-0

Englberger K, 2001. Piper auritum. In: Pest Alert, 19 Kolonia, Pohnpei, Federated States of Micronesia: SPC, Plant Protection Micronesia.

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

Florence J, Chevillotte H, Ollier C, Meyer JY, 2011. [English title not available]. (Base de données botaniques Nadeaud de l'Herbier de la Polynésie Française (PAP))., http://www.herbier-tahiti.pf

Funk V, Hollowell T, Berry P, Kelloff C, Alexander S N, 2007. Contributions from the United States National Herbarium, Washington, USA: Department of Systematic Biology - Botany, National Museum of Natural History, Smithsonian Institution. 55, 584 pp.

Gibson DN, 1974. Acathanceae. In: Fieldiana, Botany, Flora of Guatemala, 24 (10/4) 328-462.

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

Graveson R, 2012. Plants of Saint Lucia., http://www.saintlucianplants.com

Hancock I R, Henderson C P, 1988. Flora of the Solomon Islands. In: Research Bulletin - Dodo Creek Research Station, Honiara, Solomon Islands: ii + 203 pp.

Herrera K, Lorence DH, Flynn T, Balick MJ, 2010. Checklist of the vascular plants of Pohnpei with local names and uses., Lawai, Hawaii, USA: National Tropical Botanical Garden. 146 pp.

Idárraga-Piedrahita A, Ortiz RDC, Callejas Posada R, Merello M, 2011. [English title not available]. (Flora de Antioquia). In: Catálogo de las Plantas Vasculares, 2 Listado de las Plantas Vasculares del Departamento de Antioquia. 939 pp.

MacKee H S, 1994. Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie. Paris, France: Muséum National d'Histoire Naturelle. unpaginated.

Mori SA, Buck WR, Gracie CA, Tulig M, 2007. Plants and Lichens of Saba. In: Virtual Herbarium of The New York Botanical Garden, http://sweetgum.nybg.org/saba/

Smith A C, 1981. Flora Vitiensis nova: a new flora of Fiji (spermatophytes only). Volume 2. In: Flora Vitiensis nova: a new flora of Fiji (spermatophytes only). Volume 2. Kauai, Hawaii, USA: Pacific Tropical Botanical Garden. 818 pp.

Space JC, Flynn T, 2002. Report to the Government of Samoa on invasive plant species of environmental concern., Hawaii, USA: USDA Forest Service, Institute of Pacific Islands Forestry. 80 pp.

Space JC, Lorence DH, LaRosa AM, 2009. Report to the Republic of Palau: 2008 update on Invasive Plant Species., Hilo, Hawaii, USA: USDA Forest Service. 227. http://www.sprep.org/att/irc/ecopies/countries/palau/48.pdf

Thaman RR, Fosberg FR, Manner HI, Hassall DC, 1994. The flora of Nauru. In: Atoll Research Bulletin, 392 1-223.

Tropical Biology Association, 2010. Invasive plants in the Usambara Mountains, Tanzania. In: Invasive plants in the Usambara Mountains, Tanzania, http://www.tropical-biology.org/research/dip/species.htm

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

Vieria Silva VRMDa, 2002. [English title not available]. (Flora da Madeira Plantas Vasculares Naturalizadas No Arquipélago da Madeira). In: Boletim do Museu Municipal do Funchal (História Natural) supplement, 8 5-281.

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Links to Websites

Contributors

19/12/12 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