nematophagous fungi have been found throughout the world in a wide range of habitats and climates, but few from extreme environments. most studied have been the species that attack the nematodes of interest to farmers, horticulturists and foresters, but there are large numbers of species as yet undescribed. the sexual stage of "orbilia" occurs on rotting wood on land or in fresh water, while the asexual stage occurs in marine, fresh water and terrestrial habitats. "arthrobotrys dactyloides" was the first species to be discovered in brackish water, and other species have been found on mangroves.