Asclepias curassavica
{{Short description|Species of flowering plant}}
{{Speciesbox
|image = Asclepias curassavica-Thekkady-2016-12-03-001.jpg
|status = {{TNCStatus}}
|status_system = TNC
|genus = Asclepias
|species = curassavica
|authority = L.
|synonyms = Asclepias nivea var. curassavica (L.) Kuntze
}}
Asclepias curassavica, commonly known as tropical milkweed, is a flowering plant species of the milkweed genus, Asclepias.{{ cite web | title=ITIS Standard Report Page: Asclepias curassavica | url=https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=30258 | work=Integrated Taxonomic Information System | accessdate=2014-03-22 }} It is native to the American tropics and has a pantropical distribution as an introduced species. Other common names include bloodflower or blood flower, cotton bush,{{GRIN | accessdate=5 September 2014}} hierba de la cucaracha, Mexican butterfly weed, redhead, scarlet milkweed, and wild ipecacuanha.{{ cite encyclopedia | title = Common Names for Tropical Milkweed (Asclepias curassavica) | encyclopedia = Encyclopedia of Life | url = http://eol.org/pages/581283/names/common_names | accessdate=2014-03-22 }}
It is grown as an ornamental garden plant and as a food source for some butterflies, however it may be harmful to the migration patterns of monarch butterflies when used in gardens outside of its native tropical range.{{cite journal |last1=Howard |first1=Elizabeth |last2=Aschen |first2=Harlen |last3=Davis |first3=Andrew K. |title=Citizen Science Observations of Monarch Butterfly Overwintering in the Southern United States |journal=Psyche: A Journal of Entomology |date=2010 |volume=2010 |pages=1–6 |doi=10.1155/2010/689301 |doi-access=free }} Though public concern for the rapidly declining monarch population increased the demand and commercial availability of milkweed among nurseries in the US, the results have been mixed. While tropical milkweed may effectively sustain monarch larvae, the perennial growth of the plant takes ill effect on the monarchs' migratory patterns and may have other physiological effects.{{cite journal |last1=Majewska |first1=Ania A. |last2=Altizer |first2=Sonia |title=Exposure to Non-Native Tropical Milkweed Promotes Reproductive Development in Migratory Monarch Butterflies |journal=Insects |date=16 August 2019 |volume=10 |issue=8 |page=253 |doi=10.3390/insects10080253 |pmid=31426310 |pmc=6724006 |doi-access=free }} Use of the tropical milkweed in gardens has disrupted monarch migrations notably in California, Texas, Florida, and South Carolina.{{Cite web | url=http://www.fort-worth-metropolitan-area.com/nativeplantwildlifegardencom/can-milkweed-be-bad-for-monarchs/ |title = Can Milkweed be Bad for Monarchs|date = 12 January 2013}} Unlike the milkweed species native to these locations, the tropical milkweed does not go dormant in the winter causing non-migratory groups of butterflies to form. Planting Asclepias curassavica in nonnative regions therefore remains controversial and criticized. Alternatively, native milkweed species (such as showy milkweed, narrowleaf milkweed, and desert milkweed for California{{Cite news|last=Fahy|first=Claire|date=2021-06-01|title=California's Monarch Butterflies Are Down 99%. Can This Plant Help?|language=en-US|work=The New York Times|url=https://www.nytimes.com/2021/06/01/science/butterfly-habitat-california.html|access-date=2021-06-04|issn=0362-4331}}) are suggested for butterfly gardens.{{cite news |last1=Clarke |first1=Chris |title=Gardening to Help Monarch Butterflies? Plant Natives. |url=https://www.kcet.org/redefine/gardening-to-help-monarch-butterflies-plant-natives |work=KCET |date=9 January 2015 }}
It also attracts other members of the Danainae subfamily, such as the queen.
Description
Typical plants are evergreen perennial subshrubs that grow up to {{convert|1|m|ft|abbr=on}} tall and have pale gray stems. The leaves are arranged oppositely on the stems and are lanceolate or oblong-lanceolate shaped ending in acuminate or acute tips. Like other members of the genus, the sap is milky. The flowers are in cymes with 10-20 flowers each. They have purple or red corollas and corona lobes that are yellow or orange. Flowering occurs nearly year-round.{{ cite web | title=Asclepias curassavica in Flora of China | work=Flora of China @ eFloras.org | publisher=Missouri Botanical Garden | volume=23 | url=http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=200018502 | accessdate=2014-03-22 }} The {{convert|5|-|10|cm|in|abbr=on|adj=on}} long, fusiform shaped fruits are called follicles. The follicles contain tan to brown seeds that are ovate in shape and {{convert|6|-|7|mm|in|abbr=on}} long. The flat seeds have silky hairs that allow the seeds to float on air currents when the pod-like follicles dehisce (split open).{{cite web | first=Steve | last=Christman | date=2004-01-21 | accessdate=2014-03-22 | title=Asclepias curassavica: Floridata | publisher=Floridata | url=http://www.floridata.com/ref/A/ascl_cur.cfm }}
Cultivation
There are a number of different cultivars with improved flower colors and shorter habit; some have bright red, yellow or orange colored flowers. Asclepias curassavica is sometimes used in butterfly gardens (see above for concerns for monarchs) or as a cut flower. However, when the stems or leaves are broken, a poisonous milky sap exudes which can cause eye injury.{{cite journal | last1=Hsueh | first1=Kuo-Fang | last2=Lin | first2=Pei-Yu | last3=Lee | first3=Shui-Mei | last4=Hsieh | first4=Chang-Fu | title=Ocular injuries from plant sap of genera Euphorbia and Dieffenbachia | journal=Journal of the Chinese Medical Association | volume=67 | issue=2 | pages=93–98 | date=February 2004 | pmid=15146906 | url=http://homepage.vghtpe.gov.tw/~jcma/67/2/93.pdf | access-date=2011-05-01 | archive-date=2014-06-11 | archive-url=https://web.archive.org/web/20140611050731/http://homepage.vghtpe.gov.tw/~jcma/67/2/93.pdf | url-status=dead }}
Distribution
Asclepias curassavica is described by NatureServe as a "widespread species, ranging from southern North America through Central America and into South America."{{cite encyclopedia | title=Comprehensive Report Species – Asclepias curassavica | url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.129369/Asclepias_curassavica | encyclopedia=NatureServe Explorer: An online encyclopedia of life [web application] | version=7.1 | publisher=NatureServe Inc. | location=Arlington, Virginia | accessdate=2014-03-22 | last=Raker | first=C | year=1995}}
It is an introduced species in the US states of California, Florida, Hawaii, Louisiana, Tennessee, and Texas, as well as the US unincorporated territories of Puerto Rico and the United States Virgin Islands.{{cite web | title=Plants Profile for Asclepias curassavica (Bloodflower) | work=Plants Database | publisher=USDA Natural Resources Conservation Service | url=http://plants.usda.gov/core/profile?symbol=ASCU | accessdate=2014-03-22 }}
It has been introduced and naturalized in the Chinese provinces of Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangsu, Jiangxi, Qinghai, Sichuan, Xizang, Yunnan, and Zhejiang, as well as in Taiwan.
Asclepias curassavica was introduced to Australia prior to 1869 and is widespread in parts of Queensland.{{Cite web |title=Asclepias curassavica (bloodflower) |url=https://www.cabi.org/isc/datasheet/7248#tosummaryOfInvasiveness |access-date=2022-05-06 |website=www.cabi.org |language=en}} It is considered an exotic plant, and a weed, at the Meteor Downs South Project near Rolleston, Queensland, Australia.{{cite journal|title=Flora, fauna and freshwater biota assessment of the Meteor Downs South Project, near Rolleston, Central Queensland|first1=Kevin|last1=Wormington|first2=Gail |last2=Tucker |first3=Robert |last3=Black |first4=Lorelle |last4=Campbell | year=2012 | page=28 | url=http://www.goldcoastquarry.com/assets/Documents/X%20-%20Flora%20and%20Fauna%20Technical%20Report/Appendix%20X%20-%20Flora%20and%20Fauna%20Technical%20Report%20-%20Part%205.pdf | journal=EIS and Technical Reports | publisher=Gold Coast Quarry | accessdate=2014-03-30 }}
Chemistry
Asclepias curassavica contains several cardiac glycosides,{{cite journal |last1=Singh |first1=Bhagirath |last2=Rastogi |first2=R.P. |title=Cardenolides—glycosides and genins |journal=Phytochemistry |date=February 1970 |volume=9 |issue=2 |pages=315–331 |doi=10.1016/S0031-9422(00)85141-9 }} including asclepin,{{cite journal |last1=Singh |first1=B. |last2=Rastogi |first2=R.P. |title=Structure of asclepin and some observations on the NMR spectra of Calotropis glycosides |journal=Phytochemistry |date=February 1972 |volume=11 |issue=2 |pages=757–762 |doi=10.1016/0031-9422(72)80044-X }} calotropin, uzarin and their free genins, calactin, coroglucigenin and uzarigenin.{{cite journal |last1=Singh |first1=Bhagirath |last2=Rastogi |first2=R. |year=1969 |title=Chemical investigation of Asclepias curassavica Linn |journal=Indian Journal of Chemistry |volume=7 |pages=1105–1110 |url=https://www.researchgate.net/publication/285376965 }} It also contains oleanolic acid, β-sitosterol, and glycosides of asclepin. The most abundant cardiac glycoside present in Asclepias curassavica leaves is voruscharin, which comprises around 40% of the total cardiac glycoside content in leaves.{{Cite journal |last1=Agrawal |first1=Anurag A. |last2=Böröczky |first2=Katalin |last3=Haribal |first3=Meena |last4=Hastings |first4=Amy P. |last5=White |first5=Ronald A. |last6=Jiang |first6=Ren-Wang |last7=Duplais |first7=Christophe |date=2021-04-20 |title=Cardenolides, toxicity, and the costs of sequestration in the coevolutionary interaction between monarchs and milkweeds |journal=Proceedings of the National Academy of Sciences |language=en |volume=118 |issue=16 |pages=e2024463118 |doi=10.1073/pnas.2024463118 |issn=0027-8424 |pmc=8072370 |pmid=33850021|bibcode=2021PNAS..11824463A }}
Gallery
Asclepias curassavica234.jpg|Flower from flower biew
Image:Asclepias_curassavica_002.JPG|Fruits
Image:Asclepias_curassavica_003.JPG|Seeds
File:Seeds of Asclepias curassavica (Family Apocynaceae).jpg |Seed with parachute
File:Asclepiascurassavica.jpg|Seeds close up
Image:Asclepias curassavica 1854.jpg|Flower closeup
Image:Mexican Butterfly Weed Asclepias curassavica Ants 2000px.jpg|Flowers with ants feeding on the nectar
File:Danaus_plexippus-caterpillars.jpg|Monarch caterpillars feeding on milkweed.
Image:Milkweed Asclepias curassavica 'Silky Gold' Flowers 2400px.jpg|Asclepias curassavica 'Silky Gold'
File:Scarlet Milkweed with caterpillar.jpg|Scarlet milkweed with a Monarch caterpillar and large milkweed bugs
References
{{Reflist}}
External links
{{Commons category|Asclepias curassavica}}
{{Wikispecies|Asclepias curassavica L.|Asclepias curassavica}}
- [http://ucjeps.berkeley.edu/cgi-bin/get_JM_treatment.pl?583,586,592 Jepson Manual (1993)]—description of introduced species and non-native California distribution
{{Taxonbar|from=Q939991}}
{{Authority control}}
Category:Butterfly food plants
Category:Flora of Southern America
Category:Garden plants of South America