EN
Mycoflora developing on some fish species, recently introduced to Polish waters, has not been known. The authors incubated muscles of four fish species (monkey goby, Neogobius fluviatilis; racer goby, N. gymnotrachelus; Chinese sleeper, Perccottus glenii; and stone moroko, Pseudorasbora parva caught in the drainage area of the Bug River) in water taken from 6 different places. A total of 59 fungus species were found to grow on fish muscles studied: Achlya ambisexualis, A. americana, A. caroliniana, A. crenulata, A. debaryana, A. diffusa, A. dubia, A. intricata, A. klebsiana, A. oblongata, A. oligacantha, A. orion, A. polyandra, A. prolifera, A. proliferoides, A. radioasa, A. rodrigueziana, A. treleaseana, Aphanomyces irregularis, A. stellatus, Blastocladiella britannica, Blastocladiopsis parva, Catenaria verrucasa, Cladolegnia unispora, Dictyuchus monosporus, Isoachlya monilifera, Leptolegnia caudata, Leptomitus lacteus, Phlyctochytrium aureliae, Pythium afertile, P. aquatile, P. arrhenomanes, P. butleri, P. dissotocum, P. hemmianum, P. intermedium, P. myriotylum, P. ostracodes, P. periplocum, P. tenue, Rheosporangium aphamidermatus, Rhizophlyctis hirsutus, Rhizophydium laterale, R. macrosporum, Saprolegnia asterophora, S. diclina, S. eccentrica, S. ferax, S. hypogyna, S. litoralis, S. mixta, S. monoica, S. parasitica, S. pseudocrustosa, S. shikotsuensis, S. torulosa, S. uliginosa, Thraustotheca clavata, Zoophagus insidians. The results obtained may be important to ichthyopathologists, because 25 of the above-mentioned fungi are known as necrotroph or parasites of fishes.