Ascosphaera torchioi sp nov., a pathogen of osmia lignaria propinqua cresson (hymenoptera)

Ascosphaera torchioi sp. nov. differs from other described Ascosphaera by h aving larger spores, and by having residual bodies that are present within and between the spore balls, and also on the inner wall of ascocysts. The f ungus was found in mummified larvae of Osmia lignaria propinqua, a pollinat or of orchard crops. The fungus induces symptoms characteristic of those As cosphaera species that form ascocysts beneath the integument. Experimentall y, A. torchioi was found to be pathogenic to O. lignaria and O. californica . Only germination of spores and minimal hyphal growth could be obtained on artificial culture media.