Hebeloma pallidoluctuosum - A non-current Hebeloma species

According to our data Hebeloma pallidoluctuosum is not the name of a current valid species of Hebeloma. Our database has records for the following similar names

Full name: Hebeloma pallidoluctuosum Gröger & Zschiesch. (1984)
Published: Wissenschaftliche Zeitschrift der Friedrich-Schiller-Universität Jena/Thüringen. Mathematisch-naturwissenschaftliche Reihe 33 (6): 815 (1984)
Taxonomic status: Heterotypic synonym of H. sacchariolens
Notes: Replacement name for: Hebeloma latifolium Gröger & Zschiesch., Z. Mykol, 47: 198 (1981), non Hebeloma latifolium P. Karst., Krit. Öfvers. Finlands Basidsvamp. 3: 7 (1898).

Is basionym of: Hebeloma sacchariolens var. pallidoluctuosum (Gröger & Zschiesch.) Quadr. (1987)

Types: GERMANY: Thuringia, See-ecke near Ballstadt (approx. 51.0416°N, 10.7447°E, alt. approx. 330 m a.s.l.) on calcareous soil in deciduous woodland under Carpinus sp., Corylus sp., Quercus sp. and Tilia sp., 18 Sep. 1978, F. Gröger, det: Groger (Holotype. held at herbarium JE, HJB1000149).

Homotypic synonyms: Hebeloma latifolium Gröger & Zschiesch. (1981)

Original diagnosis: Locus typi: Thuringia, in silva frondosa mixta “See-Ecke”, near Ballstädt (near Goha), ad terram super formatione geologica (Muschelkalk). Leg. F. Gröger. (Holotypus in JE). Quoad odorem Hebelomati sacchariolenti. H. tomentoso, H. gigaspermo et H. fusisporo simile. Sed H. sacchariolens est species acidophila, quae manet laetiore colore usque ad summam senectutem et differ sporis laetioribus. H. tomentosum differt pileo tomentoso et habitu maiore. H. gigaspermum differ sporis maioribus et cheilocystidiis capitatis. H. fusisporum differt cheilocystidiis longioribus et sporis. Cortina nulla. Pileo albido, pallide ochraceo-griseo, fulvescente, in media parte sordide fusco-ochraceo, convexo, hemisphaerico, cum margine diu deorsum recundata, glabro. 2-4.5(6) cm. Lamellis instar coffeae cum lacte mixtae coloratis, brunneo-ochraceis, postremo valde obscuris, fere umbrinis, distantibus, latissimis, ventricosis, sinuatis, vix albomarginatis, sed mox undulatis usque crenato-serratis, non lacrimantibus. Stipite primo albido, cito fuscescente vel nigrescente (primo ad basim), sub lamellis minutissime albo-floccoso, ad basim leviter angustata sed non radicante, 2,5-4,5(6) x 0,3-0,7(1) cm. Carne primo laeta, deinde (primo ad basim) fuscescente, postea (praecipue in exsiccates) nigrescente. Odore intenso, Hebelomati sacchariolenti simili, sapore leviter amaro. Sporis 11-14,5 x 5,5-8 μm, intense luteo-fuscis, latius amygdaliformibus vel citriformibus, distincte verrucosis: pulvere brunneo. Cheilocystidiis fere lageniformibus. utriformibus usque subclaviformibus (numquam capitatis!), 33-50 x 5-12 μm.

English translation: In odour similar to H. sacchariolens, H. tomentosum, H. gigaspermum and H. fusisporum. But H. sacchariolens is an acidophilous species, which remains paler coloured to extreme old age, and differs in having more brightly coloured spores. Hebeloma tomentosum differs by the tomentose pileus and larger basidiomes. Hebeloma gigaspermum differs by larger spores and capitate cheilocystidia. Hebeloma fusisporum differs by longer cheilocystidia and spores. Cortina absent. Pileus whitish, pale ochre-grey, turning brown, at centre sordid brownochre, convex, hemispherical, with long-time involute margin, glabrous, 2–4.5(–6) cm. Lamellae with the same colour as milky coffee, brown-ochre, finally much darker, almost umber, distant, very broad, ventricose, sinuate, hardly white margin, but soon undulate then crenulate-serrate, not weeping. Stipe white at first, then turning brown or blackening (first at base), between the lamellae minutely white floccose, at base slightly narrowed and not rooting. Odour intense, like Hebeloma sacchariolens, taste slightly bitter. Spores 11–14.5 × 5.5–8 μm, intense yellow-brown, broadly amygdaloid or citriform, distinctly verrucose, in mass brown. Cheilocystidia more or less lageniform, utriform to subclaviform (never capitate), 33–50 × 5–12 μm.

Commentary: We have studied many collections of Hebeloma sacchariolens, from both base-poor and base-rich soils. We have also seen a range of pileus colours and H. sacchariolens normally has distinct buff or honey or brown tones at least in the centre of the pileus. We have studied the holotype of this species and, although we were unsuccessful in obtaining an ITS sequence, based on our analysis we have no doubt this taxon is: = Hebeloma sacchariolens Quél.