Cordyceps s.l. is a paraphyletic group of ascomycete fungi that exhibit multifunctional lifestyles, that is, as saprotrophs, endophytes, and pathogens of insects, spiders, fungi, and grasses. The family Cordycipitaceae includes macroscopically similar species that have been erroneously considered to be conspecific with Cordyceps militaris. In this study, we describe a new species within the C. militaris complex that is distributed in the Quercus-Pinus forests of central Mexico on the basis of its morphology, phylogenetic relationships, and life cycle. Phylogenetically, Cordyceps mexicana is a well-supported new sister species of the C. militaris complex. It is distinguished by the morphology of its conidiophore, host association, and geographic distribution. This species parasitizes pupae of Paradirphia sp. (Lepidoptera: Saturniidae: Hemileucinae) and might be macroscopically confused with C. militaris. Its stromata are large, can measure up to 10 cm in length, and the fertile part is always bright yellow. This species develops whitish mycelial cords that emerge from the stromata and grow toward the host. Microscopically, it develops asci with filiform ascospores disarticulating in part-spores. Its life cycle and geographic distribution are also discussed.
Keywords: 1 new taxon; Cordycipitaceae; diversity; lepidoptera; life cycle.