Cordyceps sinensis is a medicinal mushroom classified as entomopathogenic, because it lives off insects. It is known as the "caterpillar fungus" because it invades and eventually replaces the caterpillar tissue.
It was first recorded to be used in Tibet in the 15th Century, where it was known as yartsa gunbu. There is a growing body of literature indicating it has profound potential as a therapeutic agent in disease prevention and treatment. These studies are freely available to view below.