Hebeloma sinapizans (Photo: H. J. Beker)

Taxonomy

• arrow_drop_downarrow_drop_upNomenclatural notes
  The text of Paulet’s Traité des Champignons appeared in two volumes dated 1793, while the plates of the Iconographia des Champignons were issued separately in fascicles between 1808 and 1835; precise dates for the plates have not been determined, and an unknown number came out after Paulet’s death in 1826. There is uncertainty as to whether the text volumes appeared before 1808, despite the dates they bear. It has been argued that all “names” appearing in the unpaginated index to the Traité, including Fungus sinapiolens, are not validly published under Art. 23.6 as the Linnean binomial system was not consistently followed; for example, the next but one entry after ‘sinapiolens’ is for “F. ex rutilo nigrescens”. However, that requirement for consistency was deleted from the Code at the Tokyo Congress in 1993, and is missing from Art. 23.6 (c) in subsequent editions of the Code, including that currently in force (McNeill et al. 2012). In order to settle the issue as the matter also threatens the names of several common species in other genera, a proposal to suppress the index under Art. 34.1 has been made (Parra et al. 2015). Even though there is no description or diagnosis on Pl. 82, the name Hypophyllum sinapizans is nevertheless validly published there under Art. 38.1 by the reference on the plate to “Tom. 2. pag. 187” on which the description reproduced here as Fig. 46.4 (colour) from the Traité appears. Determination of the precise years of publication of the Traité and Iconographia would not affect the nomenclatural situation. For further information on the nomenclature and dates of publication see Demoulin et al. (1981) and Stafleu & Cowan (1983).

Basionym:
Hypophyllum sinapizans Paulet [“1793–1808”]., Traité des champignons 2: 82 (1793)

Types: Paulet, Traité des champignons 2: 527 (1793) pl. 82, figs. 1-3, lectotype (icon) designated by Beker et al., Hebeloma (Fr.) P. Kumm.: (2016) page 17 (MBT202923) FRANCE: Pas de Calais, Foret Domaniale de Boulogne Parcel 98 (50.6836°N, 1.7218°E, alt. approx. 70 m a.s.l.) on calcareous soil and litter in deciduous woodland pathside under Carpinus sp., Corylus sp. and Quercus sp., 10 Sep. 2010, H.J. Beker (Epitype. herbarium acc. no. BR 5020184118648, HJB13530). Epitype designated by Beker et al., Hebeloma (Fr.) P. Kumm.: (2016) page 17 (MBT202924).

• arrow_drop_downarrow_drop_upType notes
  The lectotype is from France, sine loc. from Paulet, Icon. Champ. 1: pl. 82, figs 1-3 presumed 1808 [“1808-1835“].

Homotypic synonyms:

• Fungus sinapiolens Paulet, Traité Champ. 2: unpaginated index [4] (1808?), Traite des Champignons, ouvrage dans lequel, on trouve apres l`Histoire analytique & chronologique des Decouvertes & des Travaux sur ces Plantes 2: 0 (1793)
• Derminus sinapizans (Paulet) Henn., Hymenomycetineae: 243 (1898)
• Agaricus sinapizans (Paulet) Fr. [“1836–1838”], Epicrisis Systematis Mycologici seu Synopsis Hymenomycetum: 180 (1838) ["1836-1838"]
• Hylophila sinapizans (Paulet) Quél., Ench. Fung.: 99, Enchiridion Fungorum in Europa Media et Praesertim in Gallia Vigentium: 99 (1886)

• arrow_drop_downarrow_drop_upEtymology
  Sinapizans, a derivative adjective formed by the noun base sinapis‒ mustard and the adjectival suffix ‒izans (resembling, similar). This name refers to the odour of the fungus.

• arrow_drop_downarrow_drop_upOriginal diagnosis
  Le Moutardier (pl. LXXXII, fig. 1, 2, 3). Cette espèce, que je ne trouve point décrite, est un grand champignon couleur de chair pale, qui s’élevé a la hauteur de quatre a cinq pouces, avec une étendue de chapiteau a peu-près égale, et une grosse tige blanche. Sa chair peu épaisse, est molasses et se corrompt promptement. Ses feuillets qui font presque toute l’épaisseur du chapeau, d’une substance distincte et de longueur inégale, ont jusqu’a six lignes de largeur ou de hauteur, et les plus longs adhèrent de toute cette largeur haut de la tige qu’ils embrassent; ils sont entremêles de portions de feuillets qui forment la moitie, le tiers et le quart de la longueur totale. Lorsque ce champignon sort de terre comme on le voit figure 3, les feuillets sont couleur de chair ou de cheveux ardents; ils deviennent bientôt couleur de lilas très pale, figure 1: ils sont tendres, fragiles et aqueux, et leur tranche est un peu taillée en dents de scie; mais il y en a qui, quoique de toute la longueur, ont leur tranche toute unie et n’ont que la moitie de la hauteur des autres. La tige est d’un blanc d’argent et luisante, d’environ demi-pouce et plus d’épaisseur, de substance molle et pleine d’une moelle tender et friable, avec des parois filandreuses. Toute la plante à une odeur sensible de moutarde et une saveur herbacée désagréable qui approche de celle des plantes crucifères, sans en avoir le piquant. Donnée a un chien à la dose d’un champignon, l’animal l’a rejetée en vomissant deux heures d’après; il n’en a pas résulté d’ ailleurs d’autre accident. Ce champignon, qu’on trouve en automne dans la forêt de Senard, n’a rien invite à en faire usage.

• arrow_drop_downarrow_drop_upEnglish translation
  The mustard-smelling mushroom. This species, that I have definitely not found to be described, is a large mushroom with a pale flesh colour that is about 10–12 cm high, with a pileus expanding to be about as wide, and a thick white stipe. Its context is not very thick and is soft and putrefies quickly. Its lamellae, that are about as broad as the pileus is thick, are of a distinct substance and of unequal length, they are about 15 mm broad or high, and the longest are attached over their whole width to the stipe that they embrace; they are intermixed with smaller lamellae that are half or a quarter or a third of the longest. When the fungus comes out of the ground, as is shown on figure 3, the lamellae are incarnate or the colour of red hair, they turn very soon towards a very pale lilac colour (figure 1); they are tender, fragile and watery, and their edge is slightly toothed like a saw, but there are also some that despite their length, are only half the width of the others and with a smooth edge. The stipe is silvery white and shining, about 12.5 mm thick or more, having a soft context stuffed with a tender and fragile pith, and a fibrous cortex. The whole plant has the distinct smell of mustard and a disagreeable herbaceous taste, which approaches that of some cruciferous plants, but without having the acrid component. Given to a dog in a dose of one mushroom, the animal rejected it by vomiting two hours later, which however, did not result in other harmful effects. This mushroom, which is found in autumn in the forest of Senard, has nothing inviting to make a use of it [as food].

Description

Description of Hebeloma sinapizans based on 229 collections

• arrow_drop_downarrow_drop_upMacroscopic description
  Pileus: (23) 34–88 (100) mm diameter; shape often convex, occasionally broadly umbonate, rarely umbonate, weakly umbonate, papillate or strongly umbonate; characters rarely remains of universal veil, spotting or rugulose; margin characters usually smooth, occasionally involute, rarely eroded, scalloped, crenulate, reflexed or wavy; viscosity tacky when moist; colour variation usually unicolour, rarely two color; colour at centre occasionally yellowish brown or ochraceous, rarely dark pinkish buff, clay-buff, cinnamon, cream, dark brick, pinkish buff, brick, honey, clay-red, umber or orange-brown.

  Lamellae: attachment usually emarginate, rarely free, adnate, adnexed or decurrent tooth; maximum depth 2–12 mm; number of complete lamellae 70–140; presence of tears usually absent, rarely visible with naked eye or visible with x10 lens; white fimbriate edge occasionally weak, present or absent, rarely very strong.

  Cortina presence: no.

  Stipe: (24) 34–102 (138) x (3) 9–22 (32) {median} x (4) 10–28 (77) {basal} mm; stipe Q 1.8–12.5; base shape often bulbous, occasionally clavate or cylindrical, rarely tapering; floccosity usually floccose, rarely floccose at apex, weakly floccose or pruinose; rooting no; thick rhizoids at base usually absent, rarely present;

  Context: Texture firm; stipe interior often hollow, occasionally superior wick or stuffed, rarely basal wick; stipe flesh discolouring no; slenderness measure 1.1–19.2; smell often raphanoid, occasionally strongly raphanoid, rarely cocoa or weakly raphanoid; taste often raphanoid, occasionally mild or weakly bitter, rarely bitter where recorded.

  Spore deposit colour: often umber, occasionally brownish olive.

  Exsiccata characters: occasionally lamellae blackening, rarely rich brown color, fragile, hard or shiny.

• arrow_drop_downarrow_drop_upMicroscopic description
  Spores: shape amygdaloid, usually limoniform, rarely ellipsoid; colour in microscope often brown, occasionally yellow brown, rarely yellow, brown pale or brown yellow; guttules usually yes, rarely weak or no. papilla usually yes, rarely very strongly or weak; Spore Code: O3 O4; (P0) P1 P2 (P3); D3 D4.

  Basidia: (26) 27–38 x 7–9 μm; ave. Q 3.0–4.7; spore arrangement Not recorded;

  Cheilocystidia: main shape usually lageniform or ventricose, occasionally clavate-lageniform or clavate-ventricose or cylindrical, rarely capitate; special features observed occasionally bifurcate, septa, apical thickening or geniculate, rarely clamped septa, sparse, irregular, large, many collapsed in exsiccata, median thickening or solid; cheilocystidia ratios: A/M = 1.05–1.55; A/B = 0.52–1.01; B/M = 1.50–2.17.

  Pleurocystidia: often none seen, occasionally seen, rarely only close to lamella edge.

  Ixocutis: epicutis thickness (measured from exsiccata) up to 300 μm; ixocutis hyphae width up to 8 μm; ixocutis hyphae encrustation often no, occasionally yes; shape of trama elements beneath subcutis often thickly sausage-shaped, occasionally cylindrical, angular or ellipsoid, rarely isodiametric or thinly sausage-shaped up to 30 μm wide.

  Caulocystidia: Similar to cheilocystidia but larger, up to 150 μm.

• arrow_drop_downarrow_drop_upSpore measurements

• arrow_drop_downarrow_drop_upCheilocystidia measurements

• arrow_drop_downarrow_drop_upHabitat and distribution
  Hebeloma sinapizans's preferred habitat appears to be deciduous woodland or mixed woodland with calcareous soil. Where only one possible associate was recorded, the most commonly recorded associate was Quercus (49.2%) but Fagus (27.4%), Helianthemum (11.3%), Picea (2.4%), Pinus (2.4%) and Arctostaphylos (1.6%) were also recorded. In these cases the most commonly recorded families were Fagaceae (77.4%), Cistaceae (10.2%) and Pinaceae (6.6%). We have additional records where Carpinus (8.9%), Castanea (4.0%), Betula (3.5%), Cistus (3.5%), Arbutus (3.0%), Corylus (2.5%) and Abies (2.0%) were recorded as possible associates, but in these cases a number of possible associates were mentioned. Overall the most commonly recorded families are Fagaceae (82.2%), Pinaceae (23.3%), Betulaceae (14.4%) and Cistaceae (10.9%) The growth habit of our collections was often scattered, occasionally solitary and rarely gregarious, caespitose or connate.

  According to our current collections, the species is predominantly found in Europe (89.2%) but also found in Temperate Asia (10.8%). On these continents, 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 (52.7%) and mediterranean forests, woodlands & scrub (43.2%), specifically including the ecoregions: Western European broadleaf forests (16.4%). 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 Europe we have records from the Southwest (Spain, France and Portugal), the Southeast (Italy, North Macedonia, Bulgaria and Slovenia), the Centre (Belgium, Germany, Switzerland, Czech Republic, Poland and Slovakia), the North (England, Sweden, Norway and Denmark) and Eastern Europe (Estonia). Specimens have been collected from 38.1°N to 60.5°N.

  Within Temperate Asia we have records from Western Asia (Cyprus, Turkey and Lebanon) and Caucasus (Adygea).

• arrow_drop_downarrow_drop_upMolecular results
  This species is monophyletic and well distinct from other species in all loci tested (Fig. 36; Fig. 12 (colour); Table 1, Chap. V). In some loci (Tef1a, V6 and V9) there is some intraspecific variation distinct enough for splitting the species clade in two bootstrap supported subclades. However, we have not found any subdivision consistent between the nuclear locus and the mitochondrial ones. In spite of this variation the identification of H. sinapizans based on ITS data is unproblematic. There is a soil sequence published from Iran (UDB005582) which fits H. sinapizans. Vincenot et al. (2008) amplified fungal ITS from the roots of Pyrola rotundifolia and amplified an ITS very likely belonging to H. sinapizans.

• arrow_drop_downarrow_drop_upCommentary
  Hebeloma sinapizans has predominantly ventricose (lageniform) cheilocystidia and, as a result, may be confused microscopically with members of H. sects. Hebeloma and Velutipes. There is no taxon within H. sect. Hebeloma that has large robust basidiomes or where the number of full length lamellae achieves 80. Some members of H. sect. Velutipes often have at least some ventricose cheilocystidia, for example H. quercetorum which has almost all cheilocystidia ventricose and with which this species has certainly been confused in the past. However, the large stature and robust form of H. sinapizans and the large number of full length lamellae are important characters. While H. celatum, H. erebium and H. quercetorum all have many ventricose cheilocystidia, distinguishing them from H. sinapizans is usually straightforward as H. sinapizans has considerably more full length lamellae (L = 80–120), whereas the others rarely have as many as 80 full length lamellae. Also the others often have droplets on the lamella edge, while we have never seen droplets on the lamellae of H. sinapizans. Further, the stipe of H. sinapizans never seems to discolour while that of all three H. celatum, H. erebium and H. quercetorum often discolours. Separating H. sinapizans from H. bulbiferum (the only other European member of H. sect. Sinapizantia that we recognize) is straightforward as, although both species are robust with a large number of full length lamellae, the latter species always has distinct droplets on the lamellae. Thus it is usually possible to determine H. sinapizans in the field and this identification is easy to confirm under the microscope by examining the cheilocystidia. The superior wick in the hollow stipe of H. sinapizans is a reasonably constant feature, but we do not use this character as part of the determination of this species, as it is a feature of many other taxa too. Other strong field characters of this taxon include the transversely and strongly floccose stipe and the strong raphanoid smell. Within our cited collections of H. sinapizans is one collection with hyaline spores (a ‘Hebelomina’). We have ignored the spores of this collection in forming our composite description as it is clearly atypical in respect of its spores. Also, its pileus is rather paler than we would normally expect for this taxon. But this collection has the characteristic cheilocystidia of this species and the sequences generated from DNA show no difference from our other sequences for this taxon. Like H. bulbiferum, which is phylogenetically close to H. sinapizans, the latter does occasionally have remnants of a universal veil easily visible. However, while H. bulbiferum tends to display this as remnants at the pileus margin, H. sinapizans, on the occasions it occurs, displays the remnants of this veil as a volva at the base of the stipe. Judging from the protologue of Hebeloma sinuosum, this may well be synonymous with H. sinapizans, but it is not possible to decide with certainty. An early plate of H. sinuosum (held at S, reg. no. S0525) made by Malmberg under the supervision of Fries has a strong resemblance to H. sinapizans. However, many authors, for example Kühner & Romagnesi (1953), Gröger (1961), Bruchet (1970), Moser (1983) and Vesterholt (2005), have interpreted this taxon as Hebeloma laterinum. We believe it is not possible, unambiguously, to be sure and so we do not include it as a synonym of this species.

Geographic distribution

Phenology

• arrow_drop_downarrow_drop_upAdditional cited collections

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