Hebeloma radicosoides (Photo: T. Fukiharu)

Taxonomy

Types: JAPAN: Kansai, foot of Mt. Sasama, Sekinotsu, Otsu City (approx. 35.1688°N, 138.136°E, alt. approx. 400 m a.s.l.) in mixed woodland under Pinus densiflora and Quercus serrata, 17 Oct. 1983, Y. Murakami (647) (Holotype. herbarium acc. no. TNSF 182343, HJB1000382).

• arrow_drop_downarrow_drop_upEtymology

• arrow_drop_downarrow_drop_upOriginal diagnosis
  Pileo 5-7 cm lato, obtuse conico-convexo, dein lale convexo vel applanato, frequenter obluse umbonato, margine primum in curvo, e viscido glutinoso, pallide lavo vel flavido, squamis brunneis appressis ± concentrice ornato; carne crassa, alba, sapore levi, odore debili; lamellis adnexis vel sinuatis, confertissimis, albidis dein subcinnamomeis, acie minute fimbriatis; stipitle 5-10 cm longo, 0.7-1 cm crasso, aequali vel e basi apicem versus leniter attenuato el subtus in pseudorhizam (6-9 cm) producto, pallide flavido, ad apicem pruinoso-squamuloso, sub annulo squamis brunneolis revolutis squarroso; annulo membranaceo, glulinoso, primum albo, demum brunneolo; sporis 8.7-12.6 x 4.6-6.4 μm, subamygdaliformibus, punctalis (light microscopy), irregulariter reticulalis vel rugulosis (SEM), pallide ochraceis, indexlrinoid; basidiis letrasporis; cheilocystidiis 20-28 x 5-10 μm, numerosis, clavatis vel subclavatis, hyalinis, tenuitunicatis; hyphis fibulatis.

• arrow_drop_downarrow_drop_upEnglish translation
  Pileus 5-7 cm broad, obtusely conical-convex, then broadly convex or applanate, frequently obtusely umbonate, margin at first incurved, viscid to glutinous, pale yellow to yellowish, with brown appressed scales more or less concentrically arranged; context thick, white, taste light (barely perceivable), smell faint; lamellae adnexed or sinuate, very crowded, whitish then pale cinnamon, with minutely fimbriate edge; stipe 5-10 cm long, 0.7-1 cm thick, equal or slightly tapered from the base to the apex and below lengthened (6-8 cm) into a taproot, pale yellowish, pruinose-squamulose at the apex, below the annulus rough with brownish incurved scales; annulus membranous, glutinous, white at first, then brownish; spores 8.7-12.6 x 4.6-6.4 μm, subamygdaliform, punctate (light microscopy), irregularly reticulate or rugulose (SEM), pale ochraceous, indextrinoid; basidia four-spored; cheilocystidia 20-28 x 5-10 μm, numerous, clavate or subclavate, hyaline, thin-walled; hyphae clamped.

Description

Description of Hebeloma radicosoides based on 8 collections

• arrow_drop_downarrow_drop_upMacroscopic description
  Pileus: (5) 10 (15) mm diameter; shape convex, broadly umbonate or weakly umbonate; characters often remains of universal veil; margin characters Not recorded; viscosity tacky when moist; colour variation Not recorded; colour at centre often cream or warm buff.

  Lamellae: attachment adnexed or emarginate; maximum depth not recorded; number of complete lamellae 100–120; presence of tears Not recorded; white fimbriate edge often weak, rarely absent or present.

  Cortina presence: yes.

  Stipe: (2) 6 (10) x 1 {median} x (1) 2 {basal} mm; stipe Q 2.5–6.7; base shape clavate or cylindrical; floccosity floccose at apex or pruinose at apex; rooting yes; thick rhizoids at base Not recorded;

  Context: Texture firm; stipe interior stuffed; stipe flesh discolouring Not recorded; slenderness measure up to 2.8; smell earthy or sweet; taste bitter where recorded.

  Spore deposit colour: Not recorded.

  Exsiccata characters: Not recorded.

• arrow_drop_downarrow_drop_upMicroscopic description
  Spores: shape amygdaloid, occasionally fusoid; colour in microscope yellow brown, often yellow; guttules no. papilla no; Spore Code: O2; P0 P1; (D2) D3.

  Basidia: 18–28 (29) x 5–7 μm; ave. Q 3.0–4.1; spore arrangement 4 spored;

  Cheilocystidia: main shape cylindrical; special features observed often septa, occasionally rostrate, clamped septa, many collapsed in exsiccata or short; cheilocystidia ratios: A/M = 0.96–1.17; A/B = 0.99–1.22; B/M = 0.84–1.14.

  Pleurocystidia: none seen.

  Ixocutis: epicutis thickness (measured from exsiccata) up to 350 μm; ixocutis hyphae width up to 7 μm; ixocutis hyphae encrustation yes; shape of trama elements beneath subcutis cylindrical or thickly sausage-shaped, often oblong or ovate up to 24 μm wide.

  Caulocystidia: Similar to cheilocystidia but larger, up to 28 μm.

• arrow_drop_downarrow_drop_upSpore measurements

• arrow_drop_downarrow_drop_upCheilocystidia measurements

• arrow_drop_downarrow_drop_upHabitat and distribution
  Hebeloma radicosoides's preferred habitat appears to be mixed woodland with nutrient-enriched, urea-treated soil. Where only one possible associate was recorded, the most commonly recorded associate was Quercus (50.0%) but Fagus (50.0%) were also recorded. In these cases the most commonly recorded family was Fagaceae (100.0%). We have additional records where Pinus (50.0%) and Castanopsis (16.7%) were recorded as possible associates, but in these cases a number of possible associates were mentioned. Overall the most commonly recorded families are Fagaceae (100.0%) and Pinaceae (50.0%) No growth habit has been recorded.

  According to our current collections, the species is found only in Asia-Temperate. On the continent, collections has been found in the WWF biomes The World Wildlife Fund (WWF) have divided the world into 867 terrestrial ecoregions. The ecoregion here is estimated by mapping from the GPS coordinates of the collection using data made available by Dinerstein et al (2017). Use this webtool to explore the ecoregions visually or see a full list of current ecoregions on Wikipedia. temperate broadleaf & mixed forests (85.7%) and tropical & subtropical moist broadleaf forests (14.3%), specifically including the ecoregions: Taiheiyo montane deciduous forests (42.9%), Nansei Islands subtropical evergreen forests (14.3%), Taiheiyo evergreen forests (14.3%), Nihonkai evergreen forests (14.3%) and Nihonkai montane deciduous forests (14.3%). From collector information, it appears collections have been found only in the 1.4 Forest – Temperate IUCN habitat We map from the collector's description of the habitat to the International Union for Conservation of Nature (IUCN)'s definition using a standardised set of rules. Please see this page for a full list of IUCN habitats.. Within Temperate Asia all our records are from Eastern Asia (Japan).

Geographic distribution

Phenology

• arrow_drop_downarrow_drop_upAdditional cited collections

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