Over the course of his career, Moser collected more than 25,000 mycological specimens. He first described around 420 Cortinarius species and around 80 other species, including both agarics and boletes. He circumscribed three new genera: Singeromyces (1966), Stephanopus (1975), and Anamika (2002).Horak et al. 2003b, p. 5 Much of his research concerned the Agaricales – including the classical morphotaxonomy and the chemotaxonomy of the order, as well as the toxicity of the chemical constituents of the order's members – though a further key research concern was the ecology of ectomycorrhizal symbiosis.Horak et al. 2003b, pp. 3–7
