Researchers in Korea discovered four species of Penicillium fungi that had never been reported in the country before, all isolated from freshwater environments. Using both traditional microscopic examination and modern DNA analysis, they confirmed these were new to Korea: P. contaminatum, P. jinfoshanicum, P. xuanhanense, and P. soppii. These findings suggest that Korean freshwater environments contain more fungal diversity than previously documented and may be important sources for studying fungi with potential medical and industrial applications.