Cordyceps is a fungus that grow in the higher altitudes of the Himalayas and Tibetan plateau. It is a fungal parasite that infects ants and other insects like caterpillars . It uses the carcass of the insect as food, shooting out medusa-like stems that yield spores, ready to infect another host.
Cordyceps has been prized as a medicine for centuries in Tibet and China. A number of studies have shown it has potential for treating heart disease. Currently it is approved in China to treat arrhythmia. However before taking it as supplement, it is best to consult your doctor.