 In the 19th and 20th centuries, thousands of species and infrasprecific taxa were described in the genus "Sphaerella", only to have the entire genus and about 1000 additional species redescribed into the genus "Mycosphaerella" at the end of the 20th century.The identification of "Mycosphaerella" species by morphological means is extremely difficult as these taxa produce very small fruiting structures with highly conserved morphologies, tending to grow and sporulate poorly in culture and for over 120 years, identification was based on morphology alone.These identification difficulties are amplified by the fact that up to six different species can inhabit the same lesion as either a primary or secondary pathogen, making even host-specific species difficult to identify.