 In the early decades of his careers , Moser sought to clarify the taxonomic identity of European fungi by collecting specimens to be described as <unk> in the localities studied by Elias Magnus Fries , but this was no longer necessary after changes to nomenclatural rules that took effect in 1981 . Among the Agaricales , Moser 's interest was primarily in the complex genus Cortinarius . He published book @-@ length works addressing Cortinarius taxa found in Europe and , co @-@ writing with Horak , South America . Moser , working with Joe Ammirati , contributed to research on the genus in North America , and also examined Asian and Australasian taxa . He had a particular interest in Arctic – alpine habitats , and he documented , painted and published on his collections in these and other sites around the world . Moser initially doubted the usefulness of molecular phylogenetic analysis of the Agaricales , but later contributed to research in this area . 
