Eryngium's a genus of about 230 species of annuals and perennials with hairless and usually spiny leaves, and dome-shaped umbels of flowers resembling those of thistles. The genus has a cosmopolitan distribution, with the centre of diversity in South America. Some species are native to rocky and coastal areas, but the majority are grassland plants. Common names include Sea-holly and Eryngo, the former typically being applied to coastal species, and the latter to grassland species. The flowers a… (More on Eryngium)