Phylogeny of mitosporic entomopathogenic fungi: Is the genus Paecilomyces polyphyletic?

We analyzed sequences of the divergent domain at the 5' end of the large su bunit rRNA gene from the mitosporic entomopathogenic fungi Paecilomyces sp. , Paecilomyces fumosoroseus, Paecilomyces farinosus, Paecilomyces lilacinus , Verticillium lecanii, Verticillium psalliotae, Beauveria bassiana, Ascher sonia sp., Aschersonia placenta, ascomycetous Cordyceps sp., and Cordyceps militaris. Phylogenetic analysis showed P. fumosorseus as the best characte rized out of the analyzed species with the B. bassiana clade as its sister group. Two of the P. farinosus isolates were invariably placed within the V erticillium cluster, which also contained C. militaris. The only analyzed P . lilacinus isolate appeared on the root of the hyphomycetous fungi and was characterized as the most distinct from all the hyphomycetous fungi tested . Polyphyly of the genus Paecilomyces was well supported by the Kishino-Has egawa test. In all trees based on the small subunit rRNA gene sequences obt ained from the GenBank(tm), V. lecanii, V. psalliotae, P. fumosoroseus, P. tenuipes and B. bassiana form, together with that of C. militaris, the best supported cluster in the tree. The rest of Cordyceps spp. constitute a dis tinct clade. Phylogenetic relationships derived from both tested DNA region s show polyphyly of the genus Paecilomyces and close relationships among en tomopathogenic species of the genera Verticillium, Paecilomyces, and Beauve ria.