Abstract
2036 Hieracium specimens of the herbarium of Walter Gutermann (1935–2023) kept separately at WU were revised. Six specimens were identified as belonging to previously unknown taxa, which are described as new to science here: Hieracium vilinacense, H. benzianum subsp. sveti-lovrencii, H. bifidum subsp. nudescens, H. caesium subsp. austrovelebiticum, H. cavillieri subsp. risovacense and H. oxyodon subsp. gutermannii. Hieracium fritzei, H. nigrescens subsp. nigrescens and Pilosella mirabilis are newly recorded for Austria, H. trichopsis for Italy, Pilosella schultesii for the Velebit (Croatia). P. subrubens is reported for Switzerland for the first time since 50 years.Nomenclatural and taxonomic problems in connection with the names H. atrocrinitum, H. sinuosum and H. „tiltophyllum“ are discussed. Hieracium incisum subsp. subdentatiforme is combined to H. pallescens subsp. subdentatiforme. H. cruentum subsp. naegelii is combined to Pilosella multiflora subsp. naegelii and H. schultesii subsp. tiltophyllum is raised to species rank as Pilosella tiltophylla.