Filamentous fungi are frequently isolated from body surface of the patients with suspected dermatomycosis. They may act as human pathogens, but in numerous ca - ses the significance of isolated fungus must be verified by additional investigations. The medically important fungi form a highly diverse and heterogenous group. Our often only limited knowledge of their biology is rapidly expanding particularly due to the development of new and improved methods of molecular biology., Vít Hubka, Naďa Mallátová., and 8 barev. fot.