taxonID	type	description	language	source
03A087A4C9215A3796CCD0A315BA6923.taxon	materials_examined	Type: Cortinarius crassisporus Kytöv., Niskanen & Liimat., in Niskanen (2014), Index Fungorum 201: 1. Original diagnosis: Basidiomata medium to large-sized. Pileus pale brown, brown, grey, grey brown to dark reddish brown, in some species coated by white fibrils, hygrophanous. Lamellae at first pale brown, later brown. Stipe clavate to bulbous, silky-white fibrillose. Universal veil white, in some species becoming partially pale brown, sparse or forming a couple of incomplete girdles on the stipe. Basal mycelium white. Context in pileus pale brown to brown, in stipe brownish white to pale brown, marbled hygrophanous, becoming darker brown at the base with age. Odour in lamellae indistinct. Basidiospores amygdaloid, ellipsoid, obovoid or ovoid to almost subglobose, <13.5 × 9.0 μm. Lamellar trama hyphae smooth. In deciduous and coniferous forests.	en	Fellin, Alessandro, Calledda, Federico, Frøslev, Tobias Guldberg, Armada, François, Stohn, Geert Schmidt, Brandrud, Tor Erik, Dima, Bálint, Valdagni, Alessandro, Bellanger, Jean-Michel (2024): Cortinarius (Basidiomycota, Cortinariaceae) section Crassispori revisited: resolving the C. chevassutii complex and demystifying C. variebulbus. Phytotaxa 663 (5): 247-266, DOI: 10.11646/phytotaxa.663.5.1, URL: https://doi.org/10.11646/phytotaxa.663.5.1
03A087A4C9215A3B96CCD20B143B6F3D.taxon	materials_examined	Type: — FRANCE. Gard-Hérault, Vacquières-Nîmes-Montpellier, October 1978 and October 1979, Quercus ilex, leg. G. Chevassut, holotype Henry n ° 70955 in PC herbarium, GenBank ITS MT 934956. Original diagnosis: — Pileo (4 – 10 cm lato) convexo dein convexo-plano, demum plano, tum paulum depresso, margine primo sat involuto, nonnumquam infracto-rugoso, fibrilloso griseascenti. Cute innatis fibrillis in reticulo textis, maculis pruinae griseascentis plenis praecipue insigni; colore autem griseo-brunneolo-cinerascenti pallido, dein griseo-fuliginea, demum nigro + / - maculata vel sordescenti. Lamellis (6 - 8 mm latis) distantibus, sinuato-adnatis vel emarginato-adnatis ex argillaceo-incarnatis mox fulventibus, demum umbrino-fulvis, acie haud integerrimis. Stipite (5 - 6,5 cm / 10 - 22 mm) robusto pleno, sat fragili, basi bulboso rotundato marginato, fibrilloso, griseascenti-brunneolo. Carne sordide albida vel isabellina, ad basim tandem quoque brunneo-fuliginea. Sporis ellipsoideo-ovoideo-amygdaliformibus, verruculosis (7,9 - 8,7 / 4,3 - 4,7 - 5 vel 9,4 - 10,1 / 5 μm). Basidiis 4 - sp. (33 - 39 / 8 - 8,7 μm). Hyphis fibulatis. Sub Ilicibus sat frequens. Updated description: — Pileus 3 – 10 (14) cm diam., initially globose to campanulate-convex, later plano-convex to depressed, with a broad obtuse umbo, margin lobed or notched, often fissured, involute in young specimens, then inflexed to straight. Surface dry, hygrophanous, showing a pattern of greyish brown, radial fibrils, occasionally with an overlay of micaceous, radial striae, ground colour greyish white when young, later light ochraceous or brown, at maturity tending to blacken in radially-arranged areas or striae, with whitish, scattered velar remnants occurring especially towards the centre or at margin. Lamellae adnate to emarginate, sinuous, fairly well-spaced, argillaceous, later dark brown. Edge eroded, wavy-toothed, concolorous with the faces or whitish. Stipe (3) 4 – 7 (8) × 1 – 2 cm, rather stout, cylindric, base weakly to distinctly marginate (rarely bulbous, up to 2 – 3 cm), at times bent downwards, fibrillose, initially white, grey-white or concolorous with the pileus; surface dry, crossed by shiny longitudinal fibrils, lightcoloured when young, but becoming sordid in old age. Velar remnants whitish, more or less restricted to bulb margin, basal mycelium whitish. Context off-white or brownish with red nuances and greyish tinges, more pronounced in stipe base. Odour subraphanoid with fruity notes. Macrochemical reactions KOH not tested, guaiac negative or weakly positive. Basidiospores [8, 8, 337] 7.3 – 9.7 × 4.6 – 5.6 µm, MV = 8.5 × 5.1 μm, intercarpic variation of MV = 7.9 – 9.1 × 4.9 – 5.3 µm, Q = 1.52 – 1.82, Q m = 1.67, intercarpic variation of Q m = 1.60 – 1.71, spores yellow-ochre in KOH, mostly elliptic with rounded apex or occasionally slightly tapered, more rarely subamygdaliform or pruniform with a shallow hilar depression. Ornamentation consisting of dense truncate warts, tending to coalesce towards the apex. Plage well-differentiated. Reaction to Melzer’s reagent variable, weakly to moderately dextrinoid in most of the collections analyzed (Tab. 3, Figs. 3, 6). Pileipellis suprapellis a cutis of subparallel hyphae, 2 – 7 µm wide, with cylindraceous terminal elements. Pigment brown. Subpellis differentiated, consisting of much broader hyphae, up to 20 – 25 µm wide; localized presence of yellowish brown intracellular pigment. Basidia 20 – 35 × 7 – 9 µm, tetrasporic, cylindro-clavate, hyaline or with greenish-brown intracellular pigment. Marginal cells lamellar edge sterile; hairs measuring 20 – 40 × 4 – 6 µm, cylindro-clavate in shape, at times sinuous, either unicellular or two- to three-septate, often with lateral diverticula; terminal element cylindro-clavate (15 – 20 × 5 – 7 µm). Clamp connections at all septa. Habitat and distribution: — Mainly with Quercus ilex on calcareous ground, but also with Q. pubescens and Q. cerris, in mediterranean-submediterranean regions. So far known mainly from western-central Mediterranean regions (France, Italy, Spain), Hungary, and southern temperate outposts in Germany. Material analysed: — FRANCE. Drôme, Grignan, 10 November 2018, Quercus ilex and Q. pubescens, leg. F. Armada, FA 4547; Hérault, Saint-Martin-de-Londres, 30 October 2010, Quercus ilex, leg. F. Richard, FR 10 - SML- 1; Hérault, Mas-de-Londres, 01 November 2010, Quercus ilex, leg. J. - M. Bellanger, JMB 2010110109; Hérault, Bédarieux, Levas, 23 October 2013, leg. G. Turrini, TG 2013 - 163; ibid., TG 2013 - 164; leg. G. Schmidt-Stohn, SSt 13 - 216; ibid., leg. K. Soop, KS-CO 2137; Pyrénées-orientales, Pézilla-de-Conflent, 23 November 2011, Quercus ilex, leg. E. Taschen, Pezilla 62. HUNGARY. Pest, Gödöllő, Domony valley, 26 October 1994, Quercus spp., unknown legit, CFP 1277 a in S herbarium. ITALY. Emilia Romana, Parma, Belvedere fdi Gotra di Albareto, 10 November 2014, Quercus spp., Ostrya carpinifolia, Corylus avellana, leg. F. Bellù, FB 10 - 11 - 2014; Emilia Romana, Parma, Stabielle di Borgo Val di Taro, 26 October 2014, Quercus cerris, leg. F. Bellù, FB 26 - 10 - 2014; Emilia Romagna, Bettola, Piacenza, 28 October 2018, loc. “ Montosero ”, mixed forest with Corylus, Quercus cerris, Q. pubescens and Populus tremula, leg. F. Calledda, n ° 01992 in TR-gmb herbarium; Liguria, Massaina, La Spezia, 27 October 2022, loc. “ Salterana ”, Quercus ilex, leg. F. Calledda, n ° 01994 in TR-gmb herbarium; Lombardy, Cecima, Pavia, 25 October 2009, loc. “ Ca del Monte ”, forest with Quercus pubescens and Castanea sativa, leg. F. Calledda, n ° 01991 in TR-gmb herbarium; Marche, Monte Catria, 30 November 2015, leg. E. Ludwig, 2809 - II; Toscana, San Giminiano, Siena, 01 November 1995, Quercus ilex, n ° 12546 in MCVE herbarium. SPAIN. Castellón, l’Alcalatén, Vistabella del Maestrat, Penyagolosa, Mas de l’Espino, 40 ° 15 ’ 37 ’’ N, 0 ° 20 ’ 01 ’’ W, 05 October 2015, mixed forest of Pinus nigra, P. sylvestris and Quercus ilex, leg. R. Mahiques, MES- 4613; Catalonia, Mas de Carcellara, Quercus spp., 28 October 2005, leg. K. Soop, KS-CO 1611. Comments: — Recognizing a member of the “ Cortinarius chevassutii complex ” is not too difficult morphologically, because of the unique set of features that characterize them: the marginate / submarginate basal bulb, the silky white veil, the appearance of the pileus and the small- to medium-sized spores. However, the separation of C. chevassutii sensu stricto from C. pseudobulliardioides (formerly C. chevassutii f. personatus, see below), without molecular tools, remains challenging. Our analysis of numerous confirmed collections of the two species brought to light that spore shape and length / width Q m ratio represent the most and probably only reliable diagnostic characters to tell them apart (Tab. 3, Fig. 3). Indeed, although the length values are not much different between the two species (7.1 – 9.1 µm vs 7.3 – 9.7 µm, respectively), we observed that the number of spores reaching a length of 10 – 11 µm was higher in C. chevassutii. The average Q m ratio is consistently higher in C. chevassutii (av. Q m = 1.67 vs 1.54), which can be observed also in the scatter plot (Fig. 3). We noted that the spores of C. chevassutii are mostly ellipsoid with a rounded apex, whereas those of C. pseudobulliardioides are often subamygdaliform with a tapered apex. However, for a certain, unambiguous distinction of these two species, DNA sequencing may remain necessary. Liimatainen et al. (2020) have obtained, but not included in their phylogeny, an ITS sequence of the holotype of C. subsordescens Rob. Henry, that they listed as a late synonym of C. chevassutii; this is confirmed here (Fig. 1). Henry (1985) considered C. subsordescens as a species close to C. chevassutii, but he distinguished it from the latter by the amygdaliform spore shape and the more marked degree of blackening. Some mycologists later treated this taxon as a variety of C. chevassutii, while others synonymized the two names (Fernandez-Sasia & Cadiñanos 2000; Bidaud et al. 2002). Q L / W	en	Fellin, Alessandro, Calledda, Federico, Frøslev, Tobias Guldberg, Armada, François, Stohn, Geert Schmidt, Brandrud, Tor Erik, Dima, Bálint, Valdagni, Alessandro, Bellanger, Jean-Michel (2024): Cortinarius (Basidiomycota, Cortinariaceae) section Crassispori revisited: resolving the C. chevassutii complex and demystifying C. variebulbus. Phytotaxa 663 (5): 247-266, DOI: 10.11646/phytotaxa.663.5.1, URL: https://doi.org/10.11646/phytotaxa.663.5.1
03A087A4C9215A3B96CCD20B143B6F3D.taxon	description	length (L) × width length (L) × width Q L / W total; 95 % (W) (W) species Voucher N variation; 95 % variation total (µm); MV MV MV (µm); MV XC 2013 - 176 8.1 – 9.1 – 10.2 × 8.3 – 9.1 – 9.9 × 1.45 – 1.58 – 1.44 – 1.58 – 34 (isotype) 5.3 – 5.8 – 6.1 5.4 – 5.8 – 6.2 1.74 1.72 6.8 – 8.2 – 10.2 × 7.1 – 8.2 – 9.1 × 1.30 – 1.54 – 1.40 – 1.54 – Total 449 4.7 – 5.3 – 6.1 4.8 – 5.3 – 5.8 1.74 1.74 Cortinarius 7.7 – 8.2 – 9.1 × 7.4 – 8.2 – 9.0 × 1.45 – 1.55 – 1.41 – 1.55 – AF- 110 - 2023 25 variebulbus 5.0 – 5.3 – 5.7 4.9 – 5.3 – 5.7 1.72 1.69 9.4 – 10.1 – 11.0 × 9.3 – 10.1 – 10.9 × 1.50 – 1.62 – 1.52 – 1.62 – FA 4647 35 5.7 – 6.3 – 6.9 5.7 – 6.3 – 6.9 1.77 1.72 7.6 – 8.8 – 10.6 × 7.4 – 8.8 – 10.2 × 1.47 – 1.65 – 1.47 – 1.65 – TR-gmb 01250 70 4.6 – 5.3 – 6.3 4.5 – 5.3 – 6.1 1.87 1.82 9.1 – 9.9 – 11.0 × 9.1 – 9.9 – 10.7 × 1.46 – 1.62 – 1.48 – 1.62 – FA 4772 31 5.7 – 6.1 – 6.7 5.7 – 6.1 – 6.5 1.78 1.76 8.6 – 9.0 – 10.0 × 8.2 – 9.0 – 9.8 × 1.40 – 1.52 – 1.38 – 1.52 – FR 2012204 30 5.4 – 6.0 – 6.3 5.6 – 6.0 – 6.4 1.72 1.66 9.6 – 10.4 – 12.0 × 9.4 – 10.4 – 11.4 × 1.52 – 1.67 – 1.53 – 1.67 – PML 4567 32 5.9 – 6.3 – 7.3 5.7 – 6.3 – 6.9 1.82 1.81 7.6 – 9.4 – 12.0 × 7.6 – 9.4 – 11.2 × 1.40 – 1.61 – 1.44 – 1.61 – Total 223 4.6 – 5.8 – 7.3 4.8 – 5.8 – 6.8 1.87 1.79	en	Fellin, Alessandro, Calledda, Federico, Frøslev, Tobias Guldberg, Armada, François, Stohn, Geert Schmidt, Brandrud, Tor Erik, Dima, Bálint, Valdagni, Alessandro, Bellanger, Jean-Michel (2024): Cortinarius (Basidiomycota, Cortinariaceae) section Crassispori revisited: resolving the C. chevassutii complex and demystifying C. variebulbus. Phytotaxa 663 (5): 247-266, DOI: 10.11646/phytotaxa.663.5.1, URL: https://doi.org/10.11646/phytotaxa.663.5.1
03A087A4C92D5A3E96CCD43715DA632B.taxon	materials_examined	Type: — FRANCE. Eure, under Fagus sylvatica and Carpinus betulus, on calcareous soil, 05 November 2012, leg. M. Cerutti, holotype n ° 146521 in PC herbarium, isotype XC 2013 - 176 in X. Carteret pers. herb., GenBank ITS PP 919219 and PP 919215. Original diagnosis: — Pileus (30) 50 – 70 mm, obtuse convexus, late umbonatus, circa umbonem leviter depressus; margo primum forte involuta, dein lobata, aetate fissa; indumentum lente hygrophanum, udum brunneo-fuscum (Seg. 701 - 702) vel fere nigrum, marginem versus fibrillosum, interdum rimosum; velum in umbone adpressum, album vel albo-griseum. Lamellae satis confertae, emarginataesinuatae, paulum ventriosae, brunneae vel brunneo-rufae; acie alba crenulataque. Stipes 50 – 70 × 15 mm, satis curtus, bulbosus, cum bulbum ovoideum interdum submarginatum (× 20 mm), fibrillosus, pallidus, fere spurcatus, saepe ad apicem glaucescens. Caro grisea, in stipite obscuriora, inodora. Sporae (7,5) 8 – 9,5 (10) × 5 – 5,5 (6) μm, ellipsoideae-subamygdaliformes, satis verrucosae. Habitatio in silvis frondosis calcareis. Updated description: — Pileus 3 – 12 cm diam., initially globose to campanulate-convex, later plano-convex to depressed, with a broad obtuse umbo, margin lobed or notched, often fissured, involute in young specimens, then inflexed to straight. Surface dry, hygrophanous, showing a pattern of greyish brown, radial fibrils, occasionally with an overlay of radial, micaceous striae, ground colour greyish white when young, later light brown, at maturity tending to blacken in radially arranged areas or striae, with whitish, scattered velar remnants occurring especially towards the center or on the marginal area. Lamellae adnate to emarginate, moderately spaced, argillaceous, later russet. Edge eroded, wavy-toothed, concolorous with the faces or whitish. Stipe (3) 4 – 7 (8) × 0.7 – 1.5 cm, stout, cylindrical, base weakly to distinctly marginate (rarely bulbous, up to 3 cm at base), at times bent downwards, fibrillose, crossed by shiny longitudinal fibrils, concolorous with the pileus, but becoming sordid in old age; velar remnants whitish, more or less restricted to bulb margin, basal mycelium whitish. Context off-white or light brownish with greyish tinges, more pronounced in stipe base. Odour subraphanoid. Macrochemical reactions KOH not tested, guaiac positive, very slow. Basidiospores [14, 14, 449] 7.1 – 9.1 × 4.8 – 5.8 µm, MV = 8.2 × 5.3 μm, intercarpic variation of MV = 7.6 – 9,1 × 5.1 – 5.8 µm, Q = 1.40 – 1.74, Q m = 1.54, intercarpic variation of Q m = 1.45 – 1.61 ochre-yellow or fulvous in KOH, elliptic or subamygdaliform; apex rounded or tapering; ornamentation variable, consisting of truncate or trapezoidal warts, isolate or forming short ridges, more prominent and tending to coalesce towards the apex; plage present, but hardly differentiated. Reaction to Melzer’s reagent more or less moderately dextrinoid in most collections (Tab. 3, Figs. 3, 6). Pileipellis suprapellis a cutis of subparallel hyphae, 3 – 8 µm wide, with cylindrical terminal elements. Pigment yellowish ochre. Subpellis well-differentiated, consisting of much broader hyphae, up to 25 µm wide; localized presence of brownish intracellular pigment associated with yellowish parietal pigment. Basidia 27 – 40 × 7 – 9 µm, tetrasporic, cylindro-clavate, hyaline or with greenish brown intracellular pigment. Marginal cells 15 – 35 × 3 – 4 µm, lamellar edge sterile, marginal cells in the form of hyaline, cylindro-clavate or sinuous hairs, either unicellular or twoto three-septate, often with lateral diverticula; terminal element cylindro-clavate (15 – 20 × 5 – 9 µm). Clamp connections common at all septa. Habitat and distribution: — With Quercus spp. (including Q. ilex), Carpinus betulus, Tilia cordata, possibly also Fagus sylvatica and Ostrya carpinifolia on calcareous ground. Mainly in Mediterranean-submediterranean regions, but also in locally thermophilous, temperate sites. So far known only from France, Italy (including Trentino province in N Italy), Germany, and two extreme northern outposts in the Oslofjord area of SE Norway. These Norwegian outposts are from very old, relictual, steep south-facing Tilia cordata-Quercus robur forest remnants. Material analysed: — FRANCE. Gard, Roquedur, 02 November 2012, Quercus ilex and Quercus pubescens, leg. J. - M. Bellanger, FR 2012257; Hérault, Murviel-lès-Montpellier, 01 November 1999, Quercus ilex, leg. A. Faurite- Gendron, n ° 5356 * in PC herbarium (holotype of C. chevassutii f. personatus); Isère, Saint-Marcel-Bel-Accueil, 17 October 1998, Quercus pubescens and Carpinus betulus, leg. J. Garin, PML 5357 (paratype of C. chevassutii f. personatus); Vaucluse, Cadenet, 26 November 2011, forest with Quercus pubescens and Pinus halepensis, leg. J. - M. Bellanger, JMB 2011112612; Vaucluse, Saignon, 06 November 2021, Quercus ilex, leg. J. - M. Bellanger, JMB 2021110608. GERMANY. Sachsen-Anhalt, Freyburg, FND Kleine Probstei, 01 October 2007, Quercus spp., Carpinus betulus, leg. M. Huth, HM 01.10.2007; ibid., 03 October 1995, Quercus spp., leg. M. Huth, HM 03.10.1995; Sachsen-Anhalt, Freyburg, Müncheroda, Langer Berg, 09 October 2010, Quercus spp., leg. M. Huth, HM 09.10.2010; Sachsen-Anhalt, Freyburg, Balgstädt, NSG Tote Täler, 09 September 2010, Quercus spp., leg. M. Huth, HM 09.09.2010; Sachsen-Anhalt, NSG Müncheberg, 12 October 2013, Quercus spp., Carpinus betulus, leg. G. Hensel, HG 2013 _ 071; Sachsen-Anhalt, Freyburg, Müncheroda, Schäper Holz, 12 October 2014, Quercus spp., Carpinus betulus, leg. G. Hensel & M. Huth, HG 2014 _ 185; Sachsen-Anhalt, Klosterhäseler, Metzenholz, 20 September 2014, Quercus spp., Tilia spp., Carpinus betulus, leg. G. Hensel & U. Täglich, HG 2014 _ 184. ITALY. Liguria, Genoa, Chiavari, 10 December 2022, loc. “ Le Grazie ”, Quercus ilex, leg. F. Calledda & F. Boccardo, n ° 01995 in TR-gmb herbarium; Liguria, Genoa, Camogli, Parco di Portofino, 18 November 2023, loc. “ Portofino Vetta ”, forest with Quercus ilex, leg. F. Calledda, n ° 01999 in TR-gmb herbarium (not studied); Lombardy, Varzi, Pavia, 13 October 2018, loc. “ Cella ”, forest with Ostrya carpinifolia and Quercus pubescens, leg. F. Calledda, n ° 01993 in TR-gmb herbarium; Trentino-Alto Adige, Bolzano, Settequerce, 03 November 2013, leg G. Turrini, TG 2010 - 035 b; Trentino-Alto Adige, Trentino, Madruzzo, 23 October 2019, loc. “ Castel Toblino ”, thermophilic forest with Quercus ilex and Ruscus aculeatus, leg. A. Fellin, AF- 252 - 2019; ibid., 21 November 2021, AF- 071 - 2021; ibid., 23 November 2021, AF- 077 - 2021; ibid., 17 November 2022, AF- 100 - 2022 and AF- 101 - 2022, thermophilic forest with Quercus ilex and Fraxinus ornus; Trentino-Alto Adige, Trentino, Riva del Garda, 24 October 2022, loc. “ monte Brione ”, forest with Quercus ilex and Q. pubescens, leg. A. Fellin, AF- 110 - 2022; Veneto, Treviso, Cordignano, 01 November 2007, loc. “ Villa di Villa ”, forest with Quercus ilex, leg. E. Campo, n ° 26645 in MCVE herbarium. NORWAY. Telemark, Bamble, Stokkevann east, 25 October 2014, leg. T. E. Brandrud & B. Dima, TEB 704 - 14 / DB 5559; Telemark, Porsgrunn, Blekebakken nature reserve, 29 September 1996, leg. T. E. Brandrud, TEB 29 - 09 - 1996. Comments: — This species has been treated by some mycologists as part of C. chevassutii s. l., and is better known by others as Cortinarius chevassutii f. personatus (Bidaud et al. 2002). We show here that this taxon deserves the species rank, based mainly on the well-supported phylogenetic differences, but also on some small differences in spore shape (see above). French mycologists introduced C. chevassutii f. personatus because of some distinctive “ key features ”, such as the vigorous positive reaction to guaiac on the context (“ … Carne ope gaiaco intense cyanea … ”), the size of the basidiomata (“ A typo differ statura majore pileus usque 110 mm side … ”) and the peculiar, strongly fibrillose appearance of the pileus, which is obvious in plate 405 of the Atlas des Cortinaires 12 (Bidaud et al. 2002). Such morphological features, regarded by the authors as diagnostic, are here judged ineffectual in the separation of the two taxa. All collections of the present species that we studied displayed some phenotypic plasticity for what concerns basidioma size and pileus appearance (Fig. 5), which can also be assessed by comparing the published illustrations of Cortinarius chevassutii f. personatus in the Atlas des Cortinaires 12, pl. 405 (Bidaud et al. 2002) and of C. pseudobulliardioides in the Bull. Soc. mycol. Fr., 128 (3 – 4), pl. II (Carteret & Reumaux 2012, reproduced above in Fig. 4). As to the reaction to guaiac, a test conducted on fresh material revealed that its discriminating usefulness is rather weak, since the two taxa show a wide variation in positive reactions to the reagent, with often a long response time. In summary, according to our observations, the alleged macro-morphological differences between C. chevassutii and its forma personatus, here treated under the name C. pseudobulliardioides regarding pileus, lamellae and stipe colors or the surface texture of the pileus are not easy to establish objectively, being elements of an intergrading continuum. Therefore, telling the two species apart in the field is very difficult and a reliable identification can be attained only through careful microscopy and in some cases only with sequence data. The two species are known from different countries in Europe, show an almost identical distribution pattern and certainly were confused in the past. Moreover, the two populations cover the same ecological niche represented by thermophilic deciduous forests and are associated with the same host trees (Chevassut & Henry 1982; Brandrud et al. 1998; Bidaud et al. 2002), coexisting sympatrically in the same environments. Of the three other known members of sect. Crassispori, only C. variebulbus presents risks of confusion with C. pseudobulliardioides (see below), as both C. crassisporus and C. duboisensis are conifer species with different spores and without a marginate-bulbous stipe. The former displays a transcontinental distribution in boreal or hemiboreal conifer forests of Alaska and Fennoscandia (Niskanen 2014; von Bonsdorff et al. 2015), the latter is a West North American species occurring in woodlands including Pinus ponderosa Douglas ex C. Lawson, Abies grandis (Douglas ex D. Don) Lindl. and Quercus garryana Dougl. (Li et al. 2016).	en	Fellin, Alessandro, Calledda, Federico, Frøslev, Tobias Guldberg, Armada, François, Stohn, Geert Schmidt, Brandrud, Tor Erik, Dima, Bálint, Valdagni, Alessandro, Bellanger, Jean-Michel (2024): Cortinarius (Basidiomycota, Cortinariaceae) section Crassispori revisited: resolving the C. chevassutii complex and demystifying C. variebulbus. Phytotaxa 663 (5): 247-266, DOI: 10.11646/phytotaxa.663.5.1, URL: https://doi.org/10.11646/phytotaxa.663.5.1
03A087A4C9295A2096CCD0C913136305.taxon	materials_examined	Type: — FRANCE. Vaucluse, near Avignon, 21 October 1973, Quercus ilex, leg. G. Chevassut, Henry n ° 4039 in PC herbarium, GenBank ITS PP 919229. Original diagnosis: — C. variebulbus n. sp. C. acutibulbus sat similis sed stipes et sporas diversas. Pileo (2.5 – 4 cm lato) e convexo vel convexo-obtuso demum plano, immo deformiter explanato, sicco, griseoalbidis fibrillis innatis, subargenteis subvirgato, griseofusco, griseascente, demum disco fucescente vel nigricante, alibi sordescente. Lamellis (5 – 7 mm latis) emarginatis, fulvis. Stipite (2.5 – 4 cm / 8 – 12 mm) curto, nunc subaequali nunc clavato-bulboso marginato vel submarginato, nunc recto, cylindrico, abulboso, tantum linea dubia circumdato nunc fusoideo-connato-abulboso), semper ad basim attenuato (sed non acuto), albido-fibrilloso, valde cortinato-velato (usque ad bulbum fibrilloso. Carne pallida, pallide ochracea vel pallide isabellina, inodora, dulci. Sub ilicibus gregatim. Updated description: — Pileus 4 – 7 cm diam., globose to conical-convex, at maturity plano-convex, with a broad, obtuse umbo. Pileal margin inflexed or slightly involute, occasionally with whitish velar remnants. Pileus surface mostly dry, hygrophanous, with darker innate fibrils, whitish silvery when young, with age becoming a milky coffee color or spotted fulvous-brown, especially on handling or rubbing. Lamellae moderately spaced, slightly intervenose, intercalated with short lamellulae, adnate to emarginate, light clay-coloured, then rusty ochre, finally cinnamon, edge wavy, concolorous or whitish towards the pileus margin. Stipe 3 – 6 × 1 – 2 cm, rather stout, cylindrical, base either clavate or with an oblique, submarginate bulb, somewhat enlarged (up to 3.5 cm) and roundish in shape, whitish or subconcolorous with the pileus when young, with fibrillose universal velar remnants resting more or less on bulb margin. Cortinate remnants whitish. Context whitish or pale ochraceous in the stipe. Odour faintly raphanoid, with a sweetish fragrant component. Macrochemical reactions reaction to guaiac positive, very slow, setting in after at least 5 minutes. Basidiospores [6, 6, 223] 7.6 – 11.2 × 4.8 – 6.8 µm, MV = 9.4 × 5.8 μm, intercarpic variation of MV = 8.2 – 10.4 × 5.3 – 6.3 µm Q = 1.44 – 1.79, Q m = 1.61, intercarpic variation of Q m = 1.52 – 1.67, predominantly elliptic-subamygdaliform, subovoid in front view, coarsely and densely warted, warts forming trapezoidal plaques, here and there catenulate or coalescing into short ridges, ornamentation generally more prominent towards the apex. Apex rounded or weakly tapering. Plage well differentiated. Spores more or less moderately or strongly dextrinoid to Melzer’s reagent (Tab. 3, Figs. 3, 6). Pileipellis Suprapellis a cutis of thin, cylindrical hyphae, 3 – 9 µm wide; subpellis well-differentiated, made up of broader, short-celled hyphae, 15 – 20 µm wide. Pigment intracellular and parietal, yellowish brown. Basidia 27 – 42 × 7 – 12 µm, narrowly clavate, clamped, hyaline or with brownish yellow intracellular pigment in KOH. Marginal cells Lamellar edge partially sterile; marginal cells consisting of sinuous, basidioliform, cylindro-clavate cells, interspersed with basidia, mostly unicellular, occasionally with a median septum and / or lateral diverticulum, terminal element cylindro-clavate (12 – 30 × 3 – 10 µm). Clamp connections common at all septa. Habitat and distribution: — With Quercus spp. (incl. Q. ilex), Carpinus betulus and Tilia cordata on calcareous ground, mainly in Mediterranean-submediterranean and warm thermophilous regions; known from France, Italy, Spain and thermophilous sites in Germany, north to the limestone plateau of Huy. Material analysed: — FRANCE. Drôme, Saint-Justin, 04 October 1997, mixed deciduous trees, leg. A. Bidaud, PML 4567 (paratype of Cortinarius argentatus var. griseobrunneus); Gard, Montdardier, 18 October 2012, Quercus ilex, leg. F. Richard, FR 2012204. GERMANY. Sachsen-Anhalt, Huy, Huysburg east, 04 October 2010, leg. T. E. Brandrud & G. Schmidt-Stohn, TEB 469 - 10; ibid., TEB 470 - 10; Sachsen-Anhalt, Freyburg, Kleine Probstei, NSG Tote Täler, 22 September 2014, Quercus spp., Carpinus betulus, leg. M. Huth, HM 2017 - 030; ibid., 21 October 2016, Tilia spp., Quercus spp., HM 2017 - 008; Sachsen-Anhalt, Dingelstedt, Huy, 28 September 1998, Quercus spp., leg. G. Schmidt-Stohn, SSt 98 - 220 b; ibid., 04 November 2008, SSt 08 - 175; Nordrhein-Westfalen, Wachendorf, 07 October 2007, Fagus sylvatica, leg. T. Münzmay, TM 49 - 07; Freyburg, Tote Täler, 04 November 2008, leg. G. Schmidt-Stohn, SSt 08 - 175; Huy, Dingelstedt, 27 September 2008, leg. G. Schmidt-Stohn, SSt 98 - 216 a. ITALY. Trentino-Alto Adige, Trento, 03 December 2022, loc. “ Dosso S. Rocco ”, mixed forest with Quercus cerris, Q. pubescens and Ostrya carpinifolia, leg. A. Valdagni, n ° 01250 in TR-gmb herbarium; ibid., 24 October 2020, AV- 011 - 2020 (not sequenced); ibid., 22 November 2023, leg. A. Fellin, AF- 110 - 2023 (not sequenced); ibid., 23 November 2023, leg. A. Valdagni, AF- 111 - 2023 (not sequenced). SPAIN. Jaén, Cambil, Sendero Gibralberca, 1150 m asl, 18 November 2018, Quercus ilex, Q. faginea, Pinus Pinaster, P. halepensis and various Cistaceae spp., leg. F. Armada & J. D. Reyes, FA 4647; Granada, Jàtar, Loma del Cura, 1000 m asl, 06 December 2018, Quercus ilex, Pinus halepensis and various Cistaceae spp., leg. F. Armada & M. - J. Díaz de Haro, FA 4772. Comments: — Cortinarius variebulbus is the third taxon in the C. chevassutii complex, characterized by the presence of a more or less abruptly bulbous stipe base. This species seems, however, to display the least marginated bulbous stipe when compared to C. chevassutii and C. subbulliardioides, with some specimens with a more clavatebulbous than a clearly marginate-bulbous stipe base. The spores of C. variebulbus are also, on average, slightly larger than those produced by the two other species (see Fig. 3). This taxon, together with C. chevassutii and C. acutibulbus Chevassut & Rob. Henry (1982: 40), was originally placed in subgenus Phlegmoloma Rob. Henry, introduced for a few Telamonia species displaying morphological characters normally found in Phlegmacia, including a marginate-bulbous stipe (Henry 1991). This species is characterized by medium-sized basidiomata, a pileus covered with silvery, innate, radially-arranged fibrils, tending to become greyish on a beige background, which give the surface a sparkly appearance in mature specimens, and a stipe flaring into a marginate or submarginate bulb decorated with abundant velar remnants. In the protologue, Henry compares this species to C. acutibulbus, differentiating the two species by differences in the shape of the bulb and spore shape and size. The examination of these micromorphological features in our phylogenetically confirmed collections of C. variebulbus shows that most spores have an ellipsoid or subamygdaliform shape, while some others are ovoid in front view. Spore size was also found to be more variable and overall larger than what was reported in the protologue (Tab. 3, Figs. 3, 6 vs Henry 1991). This suggests some phenotypic plasticity within C. variebulbus, and careful measurements of the spores of additional sequenced collections of this species will be welcome in the future to better assess the actual variability in spore size. In the meantime, and in the absence of reference sequence for C. acutibulbus, the synonymy of this species with C. variebulbus remains dubious. The sequence of one paratype (PML 4567) of Cortinarius argentatus var. griseobrunneus Bidaud & Reumaux in Bidaud et al. (2002: 691) is here shown to belong to C. variebulbus (Fig. 1). The lack of available sequence for the holotype of this infraspecific taxon prevents strong conclusions to be made about its conspecificity with C. variebulbus but in any case, the latter binomial would have priority at specific rank.	en	Fellin, Alessandro, Calledda, Federico, Frøslev, Tobias Guldberg, Armada, François, Stohn, Geert Schmidt, Brandrud, Tor Erik, Dima, Bálint, Valdagni, Alessandro, Bellanger, Jean-Michel (2024): Cortinarius (Basidiomycota, Cortinariaceae) section Crassispori revisited: resolving the C. chevassutii complex and demystifying C. variebulbus. Phytotaxa 663 (5): 247-266, DOI: 10.11646/phytotaxa.663.5.1, URL: https://doi.org/10.11646/phytotaxa.663.5.1
