The evergreen soursop tree is native to West Indies, Brazil, Mexico, Venezuela, and many other African countries that lie within the tropics. Soursop or Annona muricata is a member of chirimoya and pawpaw families. It is recognized by various other names such as graviola in Portugal, guanábana in Spain, and Mullaatha in South India. It looks like a custard apple, but it has a thorny skin.