Cordyceps militaris (Fr.) Link: Beobachtungen und Versuche anläßlich eines Fundes auf Tipula paludosa Meig. (Dipt., Tipul.)

Summary Cordyceps militaris was found, apparently for the first time, on a Diptera, a larva of Tipula paludosa. The coremia of the fungus on this host were not very typical and relatively small. Conidia of the isolated and cultivated fungus were injected into pupae of Hyloicus pinastn. The fungus developed on these pupae its perfect stage, in which the coremia and perithecia showed the typical shape and size of C. militaris. Reisolation on culture media yielded again the imperfect stage. It was confirmed that this conidial stage of the fungus is not identical with Paecilomyces farinosus. — The question arises now if one should compare by isolation and crossinfection (using hosts of different size) the identity of Cordyceps species which especially differ by size of coremia, and perhaps perithecia. — Strains of C. militaris cultivated for a long time (our strain 3 years, another one 6 years) were unable to produce coremia on pupae of H. pinastri inoculated by injection of conidia. — Perithecia were not produced on media with plenty of protein, i. e., on inoculated hens' eggs or media prepared with egg yolk or milk. — Trials to infect larvae and pupae of T. paludosa and Tenebrio molitor and pupae of Pieris brassicae were successful only with one larva of T. molitor. The fungus developed its mycelium and conidia on this larva kept after death in a moist chamber. After injection of conidia of C. militaris into the hemocoel of insects sometimes a higher mortality was observed compared to controls injected with sterile distilled water. However, infected dead specimens did not show typical growth of the fungus in moist chambers. Perhaps initial growth of the fungus is inhibited by excessive multiplication of the intestinal microflora of the host. Therefore, it would be advisable in further experiments to get evidence of the fungus infection by isolating the causative agent directly after the death of the host with the aid of isolation media.