Despite commonly being called paraguayos in trade, there were no peaches of any variety in Paraguay before the early-mid 15th century, and today's flat peach probably originated in China – supposedly in the 19th century,[5] but this is merely the first time they came to widespread notice in Western countries.

Later on, Wukong eats most of the rarer species of fruit in the garden and gains eternal life.

[7] Al-Bīrūnī's work describes notable crops and medicinal plants focusing on the region between Mesopotamia and today's Pakistan, and considering how easily ripe peaches spoil in transport, this variety must have been local produce (while the kernel might still be recognizably different in a dried flat peach, the shape as described by al-Bīrūnī would not).

Though al-Bīrūnī does not discuss a wide range of Chinese pharmacopoeia in his book, the central section of the Silk Road ran immediately to the north of the region where al-Bīrūnī's flat peaches were grown, and if today's flat peaches are not produced by convergent evolution, flat-peach seeds or young trees must have been traded[8] between the Mideast and China for the fruit's novelty value more than a millennium ago already.

In this case, though the direction of this trade is not readily determinable, they would be a heirloom variety more than 1000 years old.