The world's most expensive medicinal fungus is in serious decline, researchers warn in a study in the journal Biological Conservation.
Known as "Himalayan Viagra" because of its supposed libido-boosting powers, the fungus can fetch as much as USD 100 per gramme on the Chinese market, making it pricier than gold.
"There is a similar trend in other Himalayan countries, such as China, India and Bhutan," says Liu Xingzhong, a mycologist in the Chinese Academy of Sciences' Institute of Microbiology in Beijing.
On the Tibetan plateau, for instance, the fungus harvest per unit area has dropped by 10
