Nematode trapping fungi activity
About 150 species of fungi attack, kill, and digest small organisms including bacteria and nematodes. Examples:
Pleurotus ostreatus (oyster mushroom, basidiomycete). This edible mushroom that you can buy in many supermarkets has helped the human animal by providing cholesterol lowering drugs called statins, but some animals aren't so lucky. The oyster mushroom is primarily a wood decay fungus (white rot), but it also traps nematodes (roundworms) using droplets of toxin that paralyze the animal. The worms are then digested in place and nutrients absorbed by the fungal hyphae. The nematodes may provide a nitrogen supplement in the wood environment which is nitrogen poor. Pleurotus and many other wood-decay fungi will also attack and digest colonies of bacteria in agar cultures.
Arthrobotrys and Dactyllella spp. (ascomycetes). These fungi trap nematodes by diverse mechanisms, including constricting and non-constricting rings of hyphae that snare nematodes. Some of these have been shown to be anamorphs of the sexual ascomycete Orbilia, which grows on wood.
Catenaria (chytridiomycete) infects nematodes by means of swimming spores.