Caterpillar fungus (Yartsa gunbu)

Yartsa gunbu is the most expensive fungus in the world. Also known as Himalayan Viagra and many other names (such as summer grass, winter worm in Tibetan), this fungus is a parasite that infects ghost moth caterpillars, which live at altitudes between 3,000 and 5,000 m.

In the late summer, the caterpillars shed their skin, making them vulnerable to the fungus, which digests the inside of the larvae and kills/mummifies it. In the spring, the body shoots out of the caterpillar's head. The fungus supposedly has numerous benefits – it can treat asthenia, arrhytmia, night sweats, hyperlipidemia, erectile dysfunction, asthma, bronchitis, coughs, and tumors, among others.

Harvesting this fungus nets a nice salary for the locals, who harvest it during the summer. Yartsa gunbu is often used in the Chinese gift exchange culture, so it also has a significant cultural and social impact. The Chinese use the fungus as a garnish, cook it in soups, drink it with tea, or grind it up and then sell it in powder form.