clausena lansium (wampi) 黄皮

Yes! Your right! :)

We also have this fruit in Florida. People eat it here. It grows very easy with the large seed inside the fruit. The plant is native to south Asia and the Asia-Pacific. The earliest historical reference to kumquats appears in literature of China in the 12th century. They have long been cultivated in Japan, Taiwan, the Philippines and southeast Asia. They were introduced to Europe in 1846 by Robert Fortune, collector for the London Horticultural Society, and shortly thereafter into North America.