Abstract
In this study, we describe four species of Cortinarius subgen. Telamonia sect. Bovini as new to science: Cortinarius acutipes, C. cepiformis, C. schistaceus and C. sericeovelatus. We also provide updated descriptions and synonymies for several known species in the section, including C. pachypus (formerly C. terribilis and C. pseudobulbosus), C. sordescens (neotypified here), C. turgidulus and C. urbis-veteris, as well as for C. hillieri, here supported as a genuine Bovini member. In addition, through DNA sequencing of its holotype, we fix here the interpretation of C. aprinus, the iconic member of a difficult group of large, fleshy, grey brown Telamonia species often referred to as Aprini or Sordescentes. We also update the taxonomy of C. diffractosuavis (sect. Sordescentes) and C. testaceomicaceus (sect. Exsulares), to yield a most comprehensive overview of phylogenetically supported "bovinoid" species from deciduous forests on calcareous soils of Europe. The habitat and distribution of all treated species are presented, and a tentative identification key is also proposed. Citation: Schmidt-Stohn G, Bellanger J-M, Brandrud TE, Bidaud A, Oertel B, Saar G, Ballarà J, Carteret X, Reyes García JdD, Dondl B, Ploch S, Thines M, Dima B (2025). The big brown Telamonia unlocked: four new species in Cortinarius section Bovini (Agaricales, Basidiomycota) and a revised taxonomy of bovinoid Cortinarii. Persoonia 55: 1-57. doi: 10.3114/persoonia.2025.55.01.