Cordyceps sinensis

Cordyceps is a genus of ascomycete fungi that includes about 600 worldwide species. Diverse variants of cordyceps have had more than 1,500 years of use in Chinese medicine. Most Cordyceps species are end parasitoids, parasitic mainly on insects and other arthropods; a few are parasitic on other fungi. When Cordyceps attacks a host, the mycelium invades and eventually replaces the host tissue, while the elongated fruit body (ascocarp) may be cylindrical, branched, or of complex shape. The ascocarp bears many small, flask-shaped perithecia containing asci. These, in turn, contain thread-like ascospores, which usually break into fragments and are presumably infective.[