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Synnematal form of Beauveria bassiana from Hawkmoth

Image from MycoAlbum CD

Sometimes we are just lucky.   Some entomologists were working on a biocontrol project that involved rearing Hawkmoths.  During the experiments some of the larvae were killed and consumed by a remarkable fungus.  The fungus produced a tuft of yellow synnemata (fused conidiophores) with each synnema bearing an ellipsoid powdery white spore head at its tip.  There are not that many (hundreds!) synnematous Hyphomycetes so I made a mount to see if I could identify it.  I was amazed because the mount proved to be identical in all its microscopic features to Beauveria bassiana.   To confirm this I streaked some of the spores on several differend kinds of agar media.  In all cases, the fungud grew out as a typical Beauveria bassiana culture but never produced the synnemata on the petri dishes.  This is not surprising as many synnematous hyphomycetes do not produce the synnemata in culture. 

   I was impressed by all this so I sent a slide and a piece of the herbarium specimen to an authority on synnematous hyphomycetes and he didn't seem at all   surprised. Maybe he was just playing it cool.  At any rate I have never seen this remarkable form of Beauveria again nor have I chanced across anything in the literature.  

Students:  What should I have done to satisfy Koch's postulates regarding this isolate of Beauveria?