Psalliota nigricans Velenovský 1921, described from specimens found near Veltrusy in 1915, was in 1951 identified by the author with material collected in Prague-Střešovice in 1934 and published as Agaricus meleagris var. nigricans (Velen.) Pilát. Dr. V. Denkstein found many beautiful specimens of this fungus in 1967 at Budeč hill near Zákolany (Central Bohemia), which are identical with the Střešovice material but differ in several characters from the original description of Psalliota nigricans. Therefore the author describes these specimens as a new species, Agaricus velenovskyi Pilát, close to A. meleagris but distinct. It might be very similar or identical with Psalliota grisea (Pearson) Essette.
Pilát A. (1968): De Agarico velenovskyi sp. nov. [= Agaricus meleagris var. nigricans (Velen?) Pilát 1951]. – Česká Mykologie 22(2): 81–86.
