Peanut is a 1 species of Arachis in Leguminosae, commonly known as peanut. There are about 20 species of this genus, which are generally believed to be native to eastern South America and introduced to China in the16th century. Peanut originated in Brazil and is now widely introduced all over the world. In 2007, it was confirmed by experts from Xi 'an Cultural Protection Center that peanuts had appeared in the crops unearthed from the burial pit in Hanyang Mausoleum 2 100 years ago.