Cordyceps brittlebankisoides, a new pathogen of grubs and its anamorph, Metarhizium anisopliae var. majus.

A survey of entomogenous fungi was undertaken in the reserve of Wawu Mountains, Sichuan, China in July 1997. The specimens of the genus Cordyceps and other entomogenous fungi collected included C. militaris (Vuill.) Fr., C. agriota Kawam, C. nutans Pat., C. tricentri Yasuda, C. sphecocephala (K1.) Sacc., Paecilomyces cacadae (Miquel) Samson, Paecilomyces farinosus (Wize) Brown & Smith, Beauveria bassiana (Bals.) Vuill, and an unknown species which attacked a subterranean grub of a beetle (Coleoptera: Scarabaeidae). This is described here as Cordyceps together with its anamorph. A single specimen (CGAC 9728) was collected from soil in a humid forest. To obtain ascospores, the selerotium of the fresh specimen was wiped with a moist tissue and its fertile head was suspended over a sterile glass slide so that the ascospores were ejected onto the slide. The ascospores released onto the glass slide were then transferred to potato dextrose agar (PDA) tubes with a metal needle. Pieces of abdominal hyphal body (sclerotia) and stromal tissue were also transferred into PDA tubes. The same cultures from three different isolations were considered cultures of the fungus after the tubes were incubated at 23°C for 20 days. Then the specimen was air-dried and stored at 4°C. Morphological characteristics of cultures incubated on PDA and Czapek Dox agar at 23°C for 14 and 21 days were recorded. A portion of a culture exiting conidiation was fixed at room temperature in 2.5% aqueous glutaraldehyde for 12 h, followed by two washings with phosphate buffer and treatment with 2% osmium tetroxide for 2 h. Fixed material was then washed in distilled water twice and dehydrated with the following series of acetone concentrations: 30, 50, 70, 80, 90, 95, and 100% (each stage lasted about 15 min). Then the sample was criticalpoint-dried at 37°C and 1200 bar in liquid CO2. The dried sample was placed on stubs and coated with gold for 5 min. The material was examined by scanning electron microscopy and photographed. Air-dried specimens of the new collection were stored at 4°C until examination under a dissecting microscope. Contaminating debris and surface stains were removed with a fine brush and dissecting knife. Samples (0.002–0.01 g) were placed in a 1.5-ml Eppendorf