Three substrata, dung of Sylvilagus fioridanus, leaf mulch and rotting logs, from wooded areas in central Iowa are investigated for nematode-destroying fungi. Fifteen species are newly recorded for Iowa as follows: Acrostalagmus bactrosporus, Arthrobotrys cladodes var. macroides, A. dactyloides, A. robusta, Cystopage lateralis, Dactylaria candida, D. haptotyla, Dactylella bembicoides, D. ellipsospora., Harposporium helicoides, Meristacrum asterospermum, Nematoctonus haptocladus, N. leiosporus, N. robusta, and Stylopage hadra. Eight previously reported species are isolated. A species resembling Nematoctonus leiosporus but with shorter spores which were often hooked at the terminal end was found. All three substrata proved highly productive
