The taxonomy of species previously assigned to Omphalina sensu lato or Clitocybe is reevaluated in light of recent molecularly-based phylogenetic hypotheses. Nomenclatural complications involving generic and specific names, lectotypifications and changes to the Code are analysed. Lichenomphalia gen. nov. (type Hygrophorus hudsonianus, syn. Omphalina hudsoniana) is proposed for lichenized former omphalinas. Ampulloclitocybe gen. nov. (type Agaricus clavipes, syn. Clitocybe clavipes) is erected for its type species. Arrhenia is emended to include greyish species formerly included in Omphalina, but excluding reddish brown species related to Omphalina pyxidada, the conserved lectotype for Omphalina. The genera Cantharellula, Chrysomphalina, Gerronema, Glabrocyphella, Gliophorus, Haasiella, Hygrophorus, Hygrocybe, Pseudoarmillariella, and Rickenella, and the generic names Botrydina, Coriscium, Leptoglossum, Phaeotellus, Phytoconis, and Semiomphalina are discussed.