A Review on Fungal Isolates Reported as Anamorphs of Ophiocordyceps sinensis

This brief review presents current developments on Ophiocordyceps sinensis and fungal strains which have been reported as its anamorphs. A survey of literature has shown that Hirsutella sinensis is currently receiving general acceptance as a true anamorph of O. sinensis. This isolate has been confirmed as the true anamorph by both morphological and molecular methods. The other isolates such as Paecilomyces sinensis, Scytalidium hepiali, Tolypocladium sinensis, Chrysosporium sinensis, Synnematium sinensis, Paecilomyces hepiali, Mortierella hepiali, and Scytalidium hepiali have been discarded as anamorphs of O. sinensis. The review also discusses various methods used to determine or confirm anamorphs of O. sinensis. Considering that the methods have strengths and weaknesses of varying magnitudes, a collective use of various methods is recommended for more reliable conclusions. 1. Introduction Jennings and Lysek [1] define anamorph as a term for the vegetative form of reproduction (giving the conidial or imperfect state) and also the taxonomic name of the species with this form of reproduction. They describe the term teleomorph as a sexual form of reproduction and also the taxonomic state of the species with this form of reproduction. Ophiocordyceps sinensis has a sexual stage (teleomorph) and an asexual stage (anamorph). It is generally seen in the sexual stage with a stalked fruit body [2]. Ophiocordyceps sinensis is most probably a macro fungus with, by far, the highest number of isolates reported as its possible anamorphs. The question would be “how come a single species could have so many associated anamorphs with significantly varying genetic makeup, chemical profile, morphology, and growth characteristics?” Certainly, this is an indication that there is something wrong. Some mycologists have suggested that the remarkable variations within isolates from this mushroom could mean that it is not a single species but rather an association of a number of fungi. There is debate among many scientists at present whether the species of the genus Cordyceps are in fact single organisms or if they are symbiotic colonies of more than one organism. Perhaps what we are calling Cordyceps sinensis today will one day be known as a fungal/bacterial symbiosis. (Holliday et al. [3]) Zhu et al. [4] demonstrated that Paecilomyces hepiali and Hirsutella sinensis do coexist in O. sinensis. They found DNA of these fungi in both the caterpillar and fruiting bodies of natural O. sinensis. They, therefore, concluded that their results provided strong support on the multifungi