Twenty-four isolates of
Penicillium species are known, resulting in “considerable taxonomic confusion”. However, these strains are only antigenically related, having similarities in micromorphology, growth rates, toxin production, and the ability to grow in water and at low temperatures. These isolates can be grouped into nine subdivisions below the species level. There is some degree of disagreement on how to delimit
P. camemberti from closely related species, namely
P. biforme,
P. fuscoglaucum, and
P. caseifulvum. • In a traditional "lumping" scheme,
P. biforme and
P. fusoglaucum are united in
P. commune . • Ropars
et al. (2020) recognizes
P. fusoglaucum,
P. biforme, and
P. camemberti. They list two varieties under
P. camemberti: •
P. camemberti var. "camemberti", the lineage found in Camembert and Brie. White colonies, slow radial growth, fluffy mycelia. Produces cyclopiazonic acid (CPA), a mycotoxin. •
P. camemberti var. "caseifulvum", the lineage found in cheeses other than Camembert, such as St. Marcellin and Rigotte de Condrieu. Grey-green colonies, faster rate of growth on cheese (comparable to
P. biforme), unable to produce CPA. ==Toxic properties==