Full name: Hebeloma aberrans Singer (1949)
Published: Izvestiya Karelo-Finskogo Filiala Akademii Nauk SSSR 4: 96 (1949)
Taxonomic status: This is a Hebeloma but we have not been able to unambiguously determine the species.
Types: Not located. Described from Czezkin River under Alnus, Populus and Picea, Aug. 1936.

Original diagnosis: Pileo fulvidogilvo, centro atrofusco vel atrocastaneo, margine pallido, subtiliter fibrilloso e velo, viscido, centro depresso, margine convexo, dein in parte exterior plano, levi, 22-24 mm. Lamellis argillaceis, confertis, adnatis, haud lacrimantibus. Spores sordide brunneolis s.m. dilute melleis, amygdaliformi-subtriangularibus, subtiliter punctato-rugulosis, 11,5-15,8/5-8,5 μm. Cheilocystidiis c.c. 75/3,5 μm (ad apicem longissimam cylindraceam-ampulliformibus, ad basin inflatis, hyalinis). Stipite pallido, basin versus fusco, ad apicem haud farinoso sed in parte media paulum armillato-fibrilloso, apicem versus subattenuato, 60-65/4-5 mm. Carne pallida, in basi stipities fuscata rediolente. In dumetis ripae riv. Czezkin sub Alnis, Populis et Picea excels. Augusta mens. 1936.

English translation: Pileus tawny-yellow, blackish brown or blackish-chestnut brown at centre, paler at margin, subtly fibrillose from veil remnants, viscid, depressed at centre, with marginal zone convex, but in outermost part paler, smooth, 22–24 mm broad. Lamellae clay-coloured, crowded, adnate, not weeping. Spores sordid brownish, dilute honey-coloured under microscope, amygdaloid-almost triangular, subtly punctate-rugulose, 11.5–15.8 × 5.0–8.5 μm. Cheilocystidia about 75 × 3.5 μm (at apex, long-cylindrical-ampulliform, at base inflated, hyaline). Stipe pallid, brown towards base, at apex not farinose, but in middle part slightly fibrillose-girdled; slightly attenuate towards apex, 60–65 × 4–5 mm. Context pallid, in base of stipe brown, 568 with radish odour. In riverside bushes along the Czezkin river under Alnus, Populus and Picea excelsa. August 1936.

Commentary: Based on the description of the cheilocystidia and spores, this does appear likely to be a species from H. sect. Hebeloma with amygdaloid spores. The crowded lamellae and narrow cheilocystidium apex would lead towards Hebeloma sordescens or H. monticola. While H. sordescens is perhaps the most likely, it is difficult to make such an identification without seeing original material.