Cordyceps Caterpillar Fungus Powder 冬虫夏草粉Cordyceps is a fungus that lives on certain caterpillars in the high mountain regions of China. Most supplements are made with cordyceps grown in a laboratory. Cordyceps is most commonly used for kidney disorders and male sexual problems. It is also used after a kidney transplant. It is also used for liver problems, improving athletic performance, and many other conditions.