INDEPENDENT ORIGINS OF THE SYNNEMATOUS PENICILLIUM SPECIES, P-DUCLAUXII, P-CLAVIGERUM, AND P-VULPINUM, AS ASSESSED BY 2 RIBOSOMAL DNA REGIONS

Nucleotide sequences from the mitochondrial small rRNA gene and the nuclear rDNA region containing the internal transcribed spacers and 5.8S rRNA gene were determined for three synnematous Penicillium species, P. clavigerum, P. duclauxii and P. vulpinum. Trees were generated from aligned sequence data of each rDNA region using parsimony methods. The tree topologies for each rDNA region, and for the combined data set, were identical in all statistically significant branches as assessed by bootstrap analysis. Both rDNA regions support the separation of the two meiotic genera with mitotic Penicillium states, Talaromyces and Eupenicillium, into two distinct evolutionary lineages within the Eurotiales. Phylogenetic analysis demonstrated that two distinct phylogenetic origins account for the evolution of the synnematous Penicillium species examined. Penicillium clavigerum, and P. vulpinum have phylogenetic affinities with the meiotic genus Eupenicillium, while P. duclauxii is related to the meiotic genus Talaromyces and the mitotic genus Penicillium subgenus Biverticillium.