The three genera included by Donk unaccounted for elsewhere are those in which the fruitbody is strictly effused: Tomentella (including Pseudotomentella and Tomentellastrum) and Kneiffiella P. Karst. (nymenophore smooth or warty, K. being distinguished from T. by the protruding hyphaelike cystidia) and Caldesiella (hymenophore has teeth with sterile tips).
Source: wiktionary