Smodingium
African poison ivy | |
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Sprig in the Pretoria N.B.G., and a close-up view of the compound leaf | |
Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Eudicots |
Clade: | Rosids |
Order: | Sapindales |
Family: | Anacardiaceae |
Subfamily: | Anacardioideae |
Genus: | Smodingium E.Mey. ex Sond. in Harv. & Sonder (1860) |
Species: | S. argutum
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Binomial name | |
Smodingium argutum | |
species range[1]
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Smodingium argutum, the African poison ivy or pain bush,[2] is a southern African shrub or medium-sized tree in the Anacardiaceae, which has properties comparable to the American poison ivy,[3] as its sap contains heptadecyl catechols that are toxic to the skin.[1]
An immuno-chemical reaction is suspected as in other toxic anacardiaceous species.[3] It is monotypic in the genus Smodingium,[3] and was discovered in Pondoland by J. F. Drège during an 1832 expedition with the zoologist Andrew Smith.[3]
Description
[edit]It resembles Rhus species in habit and foliage. It is very variable in size, sometimes a woody shrub barely 1–2 feet high, or otherwise a tree of up to 6m. During summer it produces small, creamy green flowers arranged in large sprays.[1] The Greek generic name, meaning "durated mark",[3] alludes to its hard, flattened seeds, which are fitted with papery wings.[1] The margins of the alternately arranged, trifoliolate leaves are toothed, as suggested by its specific name, argutum, which means "sharp".[3] The foliage assumes attractive autumn colours. When damaged the twigs exude a creamy, poisonous sap, which turns black when the catechols contained in it polymerize to a melanin.[3]
Range
[edit]It occurs along the Mpumalanga escarpment, the uplands of Eswatini, the KwaZulu-Natal midlands, Pondoland and Transkei, southern Lesotho and the southern Free State.[1]
References
[edit]- ^ a b c d e "Smodingium argutum". Slide Collection (Paraclinical Sciences - Pharmacology & Toxicology). University of Pretoria.
- ^ Melissa Petruzzelloa. "7 Dangerous Plants You Should Never Touch". ENCYCLOPÆDIA BRITANNICA.
- ^ a b c d e f g Findlay, G.H. (31 August 1963). "Dermatitis of 'Poison Ivy' type from an indigenous South African plant - Smodingium argutum". S.A. Tydskrif vir Geneeskunde: 883–888.