Guy Richard Bisby (1889–1958) was an American Canadian mycologist and botanist in plant pathology. He spent his early career working as a professor at the University of Minnesota and University of Manitoba in plant pathology, and his late career as Senior Assistant Mycologist at the Imperial Mycological Institute in Kew, England. He published around fifty books and papers in mycology that extensively contributed to the taxonomy and nomenclature of fungi.[1][2]