What is "harpagophytum"

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Plate from "Icones selectae plantarum", vol. 5: t. 94 (1846)]] Harpagophytum, also called grapple plant, wood spider and most commonly devil's claw, is a genus of plants in the sesame family, native to southern Africa. Plants of the genus owe their common name "devil's claw" to the peculiar appearance of their hooked fruit. Several species of North American plants in genus Proboscidea and certain species of Pisonia are however also known by this name. Devil's claw's tuberous roots are used in folk medicine to reduce pain.