There are around 400 species of cordyceps, however they're scarce in the wild (and therefore considered unethical to harvest) and very difficult to cultivate in a laboratory, which ends up increasing the price on this sought after parasitic fungus. Today, it can cost as much as $20,000 per kilogram! Some manufacturers have developed ways to grow cordyceps on grain, referred to as cordyceps militaris. From this they create cordyceps mushroom extracts that have similar health benefits to cordyceps.