Pretty interesting. The reasoning is basically because people like to categorize fungi based on their morphology, which varies wildly depending on conditions and life stage:

> The morphology of a colony growing on a leaf or an agar surface is a snapshot of an organism at a particular stage of development. The organization of mycelia and the shapes and sizes of spores are modified by temperature, water and nutrient availability, acidity, and other environmental variables (Slepecky & Starmer 2009). This means that mycologists employ a lot of subjectivity in determining which features of phenotype are the ones that segregate species.