Ophiocordyceps sinensis

Ophiocordyceps sinensis, (synonym Cordyceps sinensis), the "vegetable caterpillar," "caterpillar fungus,"  dōng chóng xià cǎo (Chinese: 冬虫夏草), or yartsa gunbu (Tibetan: དབྱར་རྩྭ་དགུན་འབུ་) is a species of parasitic fungus that attacks Tibetan and Himalayan species of the ghost moth family, Hepialidae. The Chinese and Tibetan names refer to how the fruiting body of the fungus emerges from the burrow and body of its host caterpillar during the summer time.

O. sinensis, and several other species of Ophiocordyceps are used extensively in Traditional Chinese Medicine, though O. sinensis is the best known and most commonly used.

O. sinensis is normally consumed in the form of a tisane or honey-based capsule. One Imperial recipe calls for an ounce or so placed into a small duck to be roasted.