penicillium caseifulvum penicillium caseifulvum penicillium caseifulvum is a fungus species of the genus of penicillium which occurs on the surface of blue cheese and causes discoloration in form of brown spots. penicillium caseifulvum scientific classification kingdom: fungi division: ascomycota class: eurotiomycetes order: eurotiales family: trichocomaceae genus: penicillium species: p. caseifulvum binomial name penicillium caseifulvumfiltenborg & frisvad 1998 type strain cbs 108956, ibt 19782