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Submitted 18 October 2019, Accepted 2 January 2020, Published 31 January 2020
Corresponding Author: Buyck Bart – e-mail – bart.buyck@mnhn.fr 285
One step closer to unravelling the origin of Russula: subgenus
Glutinosae subg. nov.
Buyck B1*, Wang X-H2, Adamčíková K3, Caboň M4, Jančovičová S5,
Hofstetter V6 and Adamčík S4
1Institut pour la Systématique, Evolution, Biodiversité (ISYEB), UMR 7205, Case Postale 39 Muséum national
d’histoire naturelle, Sorbonne Université, CNRS, 12 Rue Buffon, F-75005 Paris, France
2CAS Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese
Academy of Sciences, Kunming 650201, P. R. China
3Department of Plant Pathology and Mycology, Institute of Forest Ecology, Slovak Academy of Sciences Zvolen,
Akademická 2, SK-949 01 Nitra, Slovakia
4Institute of Botany, Plant Science and Biodiversity Center, Slovak Academy of Sciences, Dúbravská cesta 9, SK-845 23
Bratislava, Slovakia
5Department of Botany, Faculty of Natural Sciences, Comenius University in Bratislava, Révová 39, SK-811 02
Bratislava, Slovakia
6Agroscope Research Station, Department of plant protection, Rte de Duiller 60, 1260 Nyon 1, Switzerland
Buyck B, Wang X-H, Adamčíková K, Caboň M, Jančovičová S, Hofstetter V, Adamčík S 2020 –
One step closer to unravelling the origin of Russula: subgenus Glutinosae subg. nov. Mycosphere
11(1), 285–304, Doi 10.5943/mycosphere/11/1/6
Abstract
This study reports on the discovery of a new subgenus, Russula subg. Glutinosae, having an
Eastern North American – East Asian distribution. A multigene phylogeny places this new
subgenus sister with strong support to a well-supported clade composed of subgenera Compactae
and Archaeae. It holds only two very rare, northern hemisphere species, the North American R.
glutinosa and the Asian R. glutinosoides sp. nov., thereby adding support to a northern hemisphere
origin of the genus. Russula fattoensis is here shown to be a synonym of R. glutinosa. Detailed
morphological descriptions and illustrations of holotype collections are provided and potential
affinities and similarities with other subgenera are discussed. The new subgenus is a perfect
illustration of the fact that nBLAST of nrITS does not always provide the appropriate sampling for
phylogenetic analyses.
Key words – BLAST – China – multi-locus – new subgenus – nrITS – phylogeny – United States
Introduction
The infrageneric classification of the genus Russula has been much debated lately in the light
of recent multi-locus phylogenies (Buyck et al. 2008, Bazzicalupo et al. 2017, Looney et al. 2016).
The latest genus phylogeny (Buyck et al. 2018) was based on a very representative sampling of the
world’s diversity of the genus and it proposed to recognize seven well-supported subgenera that
were largely congruent with features of ectomycorrhizal anatomy.
In this contribution, we report on the rather unexpected discovery of yet another new, but
very small subgenus, composed of merely two extremely rare species that were previously assumed
to belong to Russula subg. Archaeae Buyck & V. Hofst. (see Buyck & Adamčík 2013). Subgenus
Mycosphere 11(1): 285–304 (2020) www.mycosphere.org ISSN 2077 7019
Article
Doi 10.5943/mycosphere/11/1/6
286
Archaeae has always been interpreted as a good candidate for the most ancient lineage within the
genus. It was hitherto unique in being composed of species with extremely small spores, at least
when compared to those of other Russula (Buyck 1998, Buyck et al. 2017). However, the
basidiospores of species in subg. Archaeae are slightly smaller in size compared to those of genus
Multifurca Buyck & V. Hofst. and near-identical to those of some corticiaceous Russulaceae
(Buyck et al. 2008). The here newly introduced subgenus shares with subg. Archaeae similarly
small spores as well as the often puzzling resemblance of its fruiting bodies to certain species in
Hygrophoraceae, a feature first reported by Heim (1938).
The first of the two species that compose this new subgenus, R. glutinosa Fatto, was
described from New Jersey (USA) 20 years ago (Fatto 1999). Fatto placed this species in Russula
subsect. Lactarioideae Mre, a species assemblage that is part of R. subg. Brevipedum Buyck & V.
Hofst. following the latest genus phylogeny (Buyck et al. 2018). As we will demonstrate below,
this same species was later described a second time (by means of an extended Latin diagnosis, see
Buyck 2004) under the name R. fattoensis Buyck. The type specimen of the latter species was
collected during joint field excursions by Buyck and Fatto, who – at that time – failed to recognize
it as R. glutinosa. Because of its hygrophoroid habit, the extremely small spores and some other
microscopic similarities, R. fattoensis was placed in R. sect. Archaeinae Buyck & Sarnari (Buyck
2004, Buyck & Adamčík 2013), a section that was later upgraded to subgenus level (in Hongsanan
et al. 2015). A detailed and illustrated English description for R. fattoensis was never published,
hence, a detailed description of the holotype is provided below.
Sequences referring to either R. glutinosa or R. fattoensis were never part of any published
phylogenetic analysis. Yet, a nrITS sequence for R. glutinosa (obtained from a specimen collected
and identified in the field by the first author during an All Taxa Biodiversity Inventory in
Tennessee, USA) had been deposited as early as 2004 in GenBank (EU598202). During a recent
field trip to Yunnan, China, one of the collected fruiting bodies there was identified in the field
(BB) as R. glutinosa (or at least a look-alike of it) and reminded one of us (XHW) of an earlier,
possibly contaxic collection from Yunnan. The present study involves all known specimens for the
studied species and it provides their highly supported placement in the genus using the same multi-
locus phylogenetic approach as in the latest phylogeny of the genus (Buyck et al. 2018).
Materials and Methods
Morphology
Macroscopic observations of fresh basidiomata are based on the first author’s field notes and
photographs. The color notations indicated in the descriptions follow Kornerup & Wanscher
(1978). Microscopic features were re-examined and sketched by B. Buyck, S. Adamčík and S.
Jančovičová. All microscopic observations and measurements - except for basidiospores - were
made in ammoniacal Congo red, after a short aqueous KOH pretreatment to improve tissue
dissociation and matrix dissolution. All elements of the basidiomata were examined for the
presence of ortho- or metachromatic contents or incrustations in Cresyl blue as explained in Buyck
(1989). Observations and measurements of basidiospores were made in Melzer’s reagent.
Terminology related to microscopic elements follow Adamčík et al. (2019). Herbarium
abbreviations follow Index herbariorum (http://sweetgum.nybg.org/science/ih/).
Nomenclature
As already evident from the introduction above, the orthography of the names of the various
accepted or recently described new subgenera in Russula (see Hongsanan et al. 2015, Buyck et al.
2018) have here been corrected in order to conform to the rules of the Shenzen International Code
of Nomenclature for algae, fungi, and plants (Art. 21.2 on names of infrageneric taxa –
https://www.iapt-taxon.org/nomen/pages/main/art_21.html).
287
Extraction, amplification and sequencing
Total genomic DNA from American samples was extracted from dried material using the
EZNA Fungal DNA Mini Kit (Omega) according to manufacturer´s recommendations, but with
prolonged incubation time of up to 1 hr after addition of the RNA-lytic enzyme. For the two
Chinese samples, total DNA was extracted using a CTAB protocol (Doyle & Doyle 1987). Six
molecular markers were amplified (Table 1). The PCR products were purified using Exo-Sap
enzymes (Thermo Fisher Scientific, Wilmington, DE) or the Qiaquick PCR Purification Kit
(Qiagen, Hilden, Germany) or gel-purified for the Chinese samples. Samples were sequenced by
the Seqme company (Dobříš, Czech Republic) and Sangon Biotech company (Shanghai, China).
Table 1 List of molecular markers, primers and cycling protocols used in this study. (*) refers to
newly designed primers by XH Wang.
Molecular marker
Primers
Cycling
protocol
Internal transcribed spacer regions
of ribosomal DNA (nrITS)
ITS1F+ITS4 (White et al. 1990, Gardes & Bruns
1993)
Ondrušková et
al. 2017
Partial large subunit ribosomal
DNA (LSU)
LROR+LR5 (Moncalvo et al. 2000)
Pastirčáková et
al. 2018
Partial mitochondrial small subunit
of ribosomal DNA (mtSSU)
MS1+MS2 (White et al. 1990)
same as for ITS
Region between domains six and
seven of the nuclear gene encoding
the second largest subunit of RNA
polymerase II (rpb2)
bRPB2-6F+ bRPB2-7.1R (Matheny 2005)
Caboň et al.
2017
First largest subunit of RNA
polymerase II (rpb1)
Af-Russ «GARTGCCCWGGKCATTTYGG» +Cr-
Russ «CYGCAATRTCRTTGTCCATGTA» (*)
Newly designed
for his study
Transcription elongation factor 1-
alpha (tef-1α)
tef1F+tef1R (Morehouse et al. 2003) 983F+1567R
(Rehner & Buckley 2005)
526F(www.aftol.org/pdfs/EF1primer.pdf) +
«GAAATRCCNGCYTCGAATTCACC» (*)
Morehouse et al.
2003
Phylogenetic analyses
Sequence data of five partial loci (mitochondrial rDNA small subunit [mitSSU], nuclear
rDNA large subunit [nucLSU], RNA polymerase II largest [rpb1] and second largest subunit
[rpb2], and translation elongation factor 1-alpha [tef-1α]) for collections of R. glutinosoides sp.
nov., for one specimen of R. glutinosa (DMWR 04.1154) and for the holotype of R. fattoensis (see
Table 2) were added to the alignment presented in Buyck et al. (2018). This combined dataset
included 3532 characters after exclusion of ambiguous regions delimited by eye (gap regions in
variable parts of the rDNA, spliceosomal introns in protein-coding genes and a highly variable
region in RPB2 which is not unambiguously alignable based on amino-acid sequences). Maximum
likelihood analyses were conducted on the 168 specimens/5 locus dataset using RAxML-HPC2
8.2.12 (Stamatakis, 2014) on the CIPRES Science Gateway 3.3 (https://www.phylo.org/, Miller et
al. 2010) with the same settings as in Buyck et al. (2018): rapid bootstrap algorithm (RBS; option –
fa; Stamatakis et al. 2008), general time-reversible model (GTR) with the option –m GTRGAMMA
and 1000 runs each starting from a distinct heuristic starting tree (option – N 1000). Bootstrap
values were estimated based on 500 bootstrap replicates and were considered significant when ≥
70% (Alfaro et al. 2003).
Sequences of the nuclear rDNA internal transcribed spacers 1 and 2 plus the 5.8S (ITS)
were obtained for four collections of R. glutinosa, the holotype of R. fattoensis and two collections
of R. glutinosoides sp. nov. These sequences were aligned manually in MacClade v4.05 (Maddison
& Maddison 2002) together with one sequence for R. glutinosa previously deposited in GenBank
(EU598202; from Buyck 04.202). After exclusion of ambiguously aligned regions (83 characters)
the alignment used for phylogenetic analyses included 492 characters. Following the results of our
multigene analysis, subgenus Archaeae was chosen as outgroup and ITS sequences sampled among
288
GenBank deposits resulting from a previous study (Buyck et al. 2017): KY800355 for R.
archaeosuberis; KY800353 for R. cf. camarophylla; KY800350 for R. gossypina and KY800354
for R. pseudoaurantiophylla). Analyses of ITS sequences were conducted on the same server and
program (RAxML-HPC2) with the same settings but used 500 runs (option – N 500).
Table 2 Voucher table for newly generated sequences in this study. All other vouchers used in the
multi-locus analysis correspond to the voucher table provided in Buyck et al. (2018).
Extr/collector nr
Country
Herb
barcode
ITS
nucLSU
mitSSU
rpb1
rpb2
Tef-1α
Russula fattoensis
Buyck 02.227
(type)
USA
PC0125084
MN31554
5
MN31551
4
MN31553
7
-
MN32679
7
MN32680
0
Russula glutinosa
Buyck 04.202
USA
PC0125107
MN31554
4
MN31551
3
MN31553
6
-
MN32679
6
-
Buyck 04.292
USA
PC0125108
MN31554
3
MN31551
2
MN31553
5
-
MN32679
5
-
Fatto 798
USA
NY0207266
7
MN31554
2
-
MN31553
4
-
-
-
Fatto 1034 (type)
USA
NY0025350
7
MN31554
1
-
MN31553
3
-
-
-
Roody WRWV
04.1154
USA
DEWV-F-
005518
MN31554
0
MN31551
1
MN31553
2
-
MN32679
8
MN32679
9
Fatto 1142
USA
NY0207269
3
-
-
-
-
-
-
Fatto 982
USA
NY0067246
9
-
-
-
-
-
-
Russula glutinosoides
XH Wang 4578
(type)
China
KUN
HKAS,
PC0125109
MN43418
7
MN42882
7
MN46031
3
MN43368
7
MN43368
5
MN43368
9
LPT 1542
China
KUN
HKAS
MN43418
6
MN42882
6
MN46031
4
MN43368
6
MN43368
4
MN43368
8
Results
Phylogeny
The multilocus analysis (Fig. 1) strongly suggests that R. fattoensis is a synonym of R.
glutinosa and both form a fully supported monophyletic clade (BS=100%) with the sequenced
Chinese specimens. These Asian collections represent a genetically distinct sister species which is
here described as R. glutinosoides. With high support (BS=96%), the R. glutinosa - R. glutinosoides
clade is sister to a fully supported monophyletic clade (BS=100%) composed of subgenera
Compactae and Archaeae. The ITS sequences of the holotypes of R. fattoensis and R. glutinosa and
all other American specimens are identical. In the ITS phylogeny (Fig. 2) they formed a fully
supported clade (BS=100%). The two Chinese specimens also share an identical ITS sequence that
is 97% similar to the one of R. glutinosa. The phylogenetic analysis of ITS sequences places R.
glutinosa and R. glutinosoides in a strongly supported clade with a long branch that is clearly
distinct from other species with similarly small spores (i.e. Russula subg. Archaeae).
Taxonomy
Considering the phylogenetic results of the multi-locus analyses (Fig. 1), we here describe a
new subgenus to contain R. glutinosa and R. glutinosoides sp. nov.
Russula subgenus Glutinosae Buyck & X.H. Wang, subg. nov.
MycoBank number: MB 833737
289
Diagnosis. The new subgenus shares with Russula subg. Archaeae the hygrophoroid field
habit resulting from the unequal, thick and more or less spaced lamellae and the very small spores,
but differs in the more reticulate spore ornamentation, darker spore print, presence of septate
pileocystidia, the slender hyphal terminations in the pileipellis having frequently inflated apices,
and the occurrence of frequent swellings near septa.
Type species – Russula glutinosa Fatto, Mycotaxon 70:170. 1999
Figure 1 – Most likely tree obtained by ML analysis of the 168 specimens/5 locus dataset (-ln
57423.49377). Branches significantly supported are in bold and bootstrap values indicated along
the branches. Newly described taxa are in bold blue font and the new subgenus Glutinosae
indicated by the grey rectangle. For details of vouchers see voucher table provided in Buyck et al.
(2018). Note the newly introduced orthographic correction for names of accepted subgenera in
Russula.
290
Figure 2 – Most likely tree obtained by ML analysis of the ITS dataset (-ln = 1319.94811).
Branches significantly supported are in bold and bootstrap values indicated along the branches. The
newly sequenced specimens are in bold and the new species is in bold blue. Voucher information
for out-group species is given in Buyck et al. (2018).
For the sake of completeness, we first provide here a full description for the holotype of R.
fattoensis as this was never published.
Russula fattoensis Buyck, Cryptogamie, Mycologie 25 (2): 181. 2004 Figs 3, 4, 11a-b
Original description
Pileus usque ad 89 mm diam., regularis, plano-depressus, firmus, carnosus; margo laevis,
juventu involutus; pileipellis secernens usque ad 1/4 radii, paulum viscosa, lucens sicco, continua,
haud pruinosa, rubro-brunnea sed marginem versus cito pallidior et cremea vel albida. Lamellae
adnatae, normaliter dispositae (plus minusve 1/mm), 5-6 mm altae, haud fragiles, interstitiis
venosae, tactu roseo-brunnescentes, lamellulis numerosis saepe brevibus intermixtae; acies
concolor, integra. Stipes 46-49 × 15-23 mm, cylindratus, irregulariter... in parte basale, laevis,
albus, griseus basim versus tactu brunnescens, firmus, durus, plenus. Caro alba, mox rubro-brunnea
vel brunneo-rosea, stipiti base grisescens, inodora, fortiter interdum tarde acris. Sporae albae in
cumulo. Caracteres microscopici R. earlei affines.
Holotypus: America borealis, Nova Caesarea, in sylvis frondosis praecipue fagetis, in
herbario PC conservatus sub numero Buyck 02.227.
Type study
Pileus up to 89 mm in diam., quite regular in outline, slightly depressed to plane in the center,
firm and quite thick (11–12 mm above lamellar attachment); margin smooth, involute when young;
cuticle shortly peeling (up to ¼ of the radius), slightly viscose when humid, shiny when dry, not
pruinose, smooth and continuous, occasionally fissuring from drought, warm reddish brown
291
(5DE7–8 in the center, becoming rapidly much paler (5C5–7), cream (4A2–4) to whitish toward the
margin. Lamellae unequal with many lamellulae of different lengths, especially many short ones,
adnate, moderately spaced (approx. 1 L+l/mm near the pileus margin), 5–6 mm high, thick, often
splitting transversely, not easily breaking when touched, strongly anastomosing between lamellae
near the pileus context, not forked near the stipe attachment, but occasionally so closer to the pileus
margin, cream and staining brownish pink where injured or upon handling; edge even, concolorous.
Spore producing surface abruptly delimited from the sterile stipe surface. Stipe 46–49 × 15–23 mm,
central, cylindrical but narrowing and irregularly wrinkled-deformed at the base, smooth, glabrous,
chalky white, greyish near the base and browning from injuries, firm and very hard, massive and
without cavities. Context white, but quickly reddish brown to brownish pink when cut, distinctly
grey in the stipe lower half, certainly in young specimens. Odour weak, not unpleasant. Taste very
acrid, typically after a few seconds. Spore print first seemingly white, warm cream [II(b–)c code
Romagnesi] when scraped together. Exsiccatum yellowish brown, shiny, darker at the center.
Spores broadly ellipsoid to ellipsoid, (4.8–)4.9–5.3–5.6(–6.1) × (3.5–)3.7–3.9–4.2(–4.5) μm,
Q=(1.25–)1.28–1.34–1.4(–1.47); ornamentation low, subreticulate, composed of numerous [(8–)9–
12(–13) warts in a 3 μm diam. circle on spore surface], moderately amyloid, obtuse warts [(8–)9–
12(–13) warts in a 3 μm diam. circle on spore surface], 0.1–0.2 μm high, connected by numerous
fine line connections [3–5(–7) in the circle] or frequently fused in pairs or short chains [(1–)3–6(–
7) fusions in the circle]; suprahilar spot inamyloid, inconspicuous, small. Basidia (32–)37.5–41.5–
45.5(–50) × 5.5–6–7(–7.5) μm, 4–spored, narrowly clavate to subcylindrical; basidiola first
cylindrical, then narrowly clavate. Hymenial gloeocystidia very abundant on lamellar sides, ca.
5500–7500 per mm2, (34–)42–56.5–71(–84) × 4.5–5.5–6(–7) µm, narrowly clavate to
subcylindrical, with obtuse tips, occasionally apically slightly constricted, thin-walled, without
appendage, not mucronate, for the larger part filled with heteromorphous (granular or crystalline)
contents that are moderately graying in sulfovanilin; at the lamellar edge more dispersed and
usually shorter, (16–)22.5–28.5–34(–40) × 4–4.5–5(–5.5) µm, with less abundant contents.
Marginal cells occupying most of the lamellar edges, (10–)12.5–16–19(–22) × 3–4–4.5(–5) µm,
similar in shape to basidioles but smaller, cylindrical or narrowly clavate, often slightly moniliform,
obtuse–rounded at the tips. Subhymenium pseudoparenchymatic. Lamellar trama containing of
sphaerocytes. Pileipellis orthochromatic in Cresyl blue, not sharply delimited from the underlying
sphaerocytes of the context, ca. 220–230 μm deep; vaguely two-layered. Suprapellis ca. 120–150
μm deep, composed of erect, rarely branched, strongly gelatinized and relatively dense hyphal
endings composed of very few cells. Subpellis very dense, pseudoparenchymatic, less gelatinized,
ca. 90–110 μm thick, composed of 4–15 μm wide hyphae. Acidoresistant incrustations absent.
Terminal cells near the pileus margin (17–)24–35–45.5(–61) × (3–)3.5–4–5(–6) µm, cylindrical,
apically obtuse and usually distinctly inflated to capitate, rarely constricted, also near basal septum
often swollen; subterminal cells usually not branched, distinctly inflated near the proximal septum
and there 5–9 µm wide. Terminal cells at the pileus center similar to those near the margin but
more distinctly capitate, (25–)28.5–40–52(–83) × (3.5–)4–5–5.5(–6.5) µm; subterminal cells more
often branched, usually inflated near the proximal septum. Pileocystidia near the pileus margin
1(2–3)-celled, subcylindrical, apically obtuse or rarely constricted, straight or occasionally
flexuous, thin-walled, (29–)30–62–93(>150) × 3.5–4.5–5.5(–6.5) µm, some very long and
originating deep in the trama, contents in Congo red in major part heteromorphic granulose or
banded, weakly reacting in sulfovanilin, yellow-green in Cresyl blue. Pileocystidia at the pileus
center smaller, cylindrical, often flexuous and apically mucronate or with small capitulum,
measuring ca. 27–82 × 3–5 µm, optically empty or with poor heteromorphic contents, at their
surface bearing a yellow incrustation that does not react to any reagents. Cystidioid hyphae present
in subpellis, in particular just above the pileus context, also continuing deeper in pileus and
lamellar trama, mostly septate and bearing the same yellow incrustations, turning brownish grey in
sulfovanillin. Clamp connections absent in all parts.
292
Figure 3 – Russula fattoensis (holotype). Microscopic features of the hymenium. A Basidia. B
Basidiola. C Marginal cells on the lamellar edges. D Spores. E Hymenial gloeocystidia near the
lamellar edges. F Hymenial gloeocystidia on the lamellar sides. Cystidia with contents as observed
in Congo Red, some elements with contents indicated schematically by a plus sign (+). Scale bars =
5 μm for spores and 10 μm for all other elements. Drawings S. Jančovičová and S. Adamčík.
Figure 4 – Russula fattoensis (holotype). Microscopic features of the pileipellis. A Pileocystidia
near the pileus center. B Pileocystidia near the pileus margin. C Hyphal terminations near the pileus
center. D Hyphal terminations near the pileus margin. Cystidial contents as observed in Congo Red.
Scale bars = 10 μm. Drawings S. Jančovičová and S. Adamčík.
293
Russula glutinosa Fatto, Mycotaxon 70:170. 1999 Figs 5-8, 11, 12a-c, 13b-c
Original diagnosis
Pileus 6-9 cm latus, convexus, maturans ad plano-depressum; margo aequus; cutis glutinosa,
resiliens, separabilis usque ad 1/3 partem radii, albida ad pallide ochraceam, media cutis leviter
luteo-fusca; trama dura, immutans. Lamellae adnatae, subdistantes, cum abundantibus lamellulis,
cremeis, immutantibus, sapor acer. Stipes ad 6 x 2 cm, cremeus, glaber, firmus, immutans. Sporae
cremeae (Romagnesi IIc), 5-7 x 4-5 µm, flocculae 0.1 µm altae, segregatae aut cum paucis
gracilibus connectivis. Cystidia hymenialia 60-85 x 4-6 µm, abundantia, completa granulis reflexis-
griseolis. Pileus cutis ad 300 µm crassam, desidens in matrice gelatinosa, extendens usque ad 280
µm supra extremas hyphae; pileus subcutis habens hyphas libratas-contextas 2-4 µm latas; pileus
epicutis habens trichodermis hypharum hyalinarum 2-4 µm lata, sine pileocystidiis. Hyphae stipitis
cuticis similes cutici pilei, sed cum multis oleiferis extremis hyphis 3-5 µm latis cum reflexo-
griseolo contento.
Holotypus: Lectus a R.M. Fatto 1034, in Mendham town park, Morris County, New Jersey,
USA. 6 August 1997. Conservatus in herbario New York Botanical Garden (NY).
Type study
Spores ellipsoid, (5.0-)5.2-5.5-5.8(-6.2) × (3.6-)3.7-4-4.2(-4.3) μm, Q=(1.25-)1.33-1.39-
1.46(–1.5); ornamentation subreticulate, composed of 0.1(–0.2) μm high, amyloid warts [(8–)9–
11(–12) warts in a 3 μm diam. circle on the spore surface], connected by numerous fine line
connections [(2–)3–6(–7) line connections in the circle] and frequently also fused in pairs or short
chains [(1–)2–5(–7) fusions in the circle]; suprahilar plage inamyloid, smooth, small and ill–
defined. Basidia (39–)42–46–51(–53) × (4.5–)5–6–6.5(–7.5) μm, 4-spored, narrowly clavate to
subcylindrical; basidiola first cylindrical, then narrowly clavate. Subhymenium narrowly
pseudoparenchymatic. Lamellar trama with sphaerocytes. Hymenial gloeocystidia on lamellar sides
numerous, ca. 2000–3000 per mm2, (57–)65–80–95(–112) × (4.5–)5–5.5–6 µm, narrowly clavate,
narrowly fusiform to subcylindrical, with mostly acute tips, often apically prolonged with a 3–8 µm
long appendage, containing granular or crystalline contents that react weakly in sulfovanillin; at the
lamellar edge dispersed, similar but usually shorter, (31–)41.5–51–60(–65) × 4.5–5.5–6(–7) µm.
Marginal cells very abundant, in shape similar to basidioles but smaller, cylindrical or narrowly
clavate, obtuse, often slightly moniliform, measuring (10–)13.5–18–22.5(–24) × 3–3.8–4.5(–5) µm.
Pileipellis orthochromatic in Cresyl blue, not sharply delimited from the underlying context, ca.
180–210 μm deep, vaguely divided in ca. 50–70 μm deep suprapellis of erect or ascending,
sometimes basally branched, strongly gelatinized and narrow hyphal endings, and a very dense, less
gelatinized, ca. 130–150 μm deep subpellis of 3–8 μm wide, intricate hyphae that become gradually
more horizontally oriented towards pileus context, often more or less strongly inflated near septa.
Hyphal terminations composed of 2–4 subcylindrical cells, narrow except sometimes near septa;
terminal cells near the pileus margin measuring (12–)15–20–25.5(–34) × 2.5–3.5–4(–5) µm,
cylindrical, the very tip obtuse and frequently inflated to almost capitate; terminal cells near the
pileus center longer than those near the margin, often subcapitate or occasionally distinctly capitate,
measuring (17–)24–35–46.5(–65) × (2–)2.5–3–4(–5) µm; subterminal cells mostly unbranched,
usually shorter, often distinctly inflated near the proximal septum. Pileocystidia near the pileus
margin inconspicuous, thin-walled, small, narrow, (1–)2–3-celled, subulate to subcylindrical,
apically attenuated or mucronate, straight or slightly flexuous; terminal cells (15–)18.5–25–31(–37)
× 2–2.5–3(–3.5) µm, mostly optically empty in Congo red, but some with few inclusions or in
apical part yellowish and refringent, insensitive to sulfovanillin, in more basal parts encrusted with
yellow incrustations that stain yellow-green in Cresyl blue, and red after karbolfuchsin treatment;
those in the pileus center similar but with narrower and longer terminal cells, measuring (1.5–
)18.5–31–43(–70) × (1.5–)2–2.5–3(–3.5) µm, apically attenuated and usually mucronate, with
similar contents and incrustations as those near margin. Cystidioid hyphae in subpellis and trama
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present, dispersed, with more conspicuous, distinctly heteromorphous contents in Congo red.
Clamp connections absent in all parts.
Figure 5 – Russula glutinosa (holotype). Microscopic features of the hymenium. A Basidia. B
Basidiola. C Marginal cells on the lamellar edges. D Spores. E Hymenial cystidia on the lamellar
edges. F Hymenial cystidia on the lamellar sides. Cystidia with contents as observed in Congo Red,
some elements with contents indicated schematically by a plus sign (+). – Scale bar equals 5 μm for
spores and 10 μm for all other elements. Drawings S. Jančovičová and S. Adamčík.
Figure 6 – Russula glutinosa (holotype). Microscopic features of the pileipellis. A Pileocystidia
near the pileus center. B Pileocystidia near the pileus margin. C Hyphal terminations near the pileus
center. D Hyphal terminations near the pileus margin. Cystidial contents as observed in Congo Red.
Scale bar = 10 μm. Drawings by S. Jančovičová and S. Adamčík.
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Figure 7 – Russula glutinosa. Microscopic features (WRWV 04.1154). A. Pileocystidia near the
pileus margin. B. Basidia and basidiola. C. Hymenial gloeocystidia. D. Basidiospores as observed
in Melzer’s reagent. Scale bars = 5 μm for spores, 10 μm for all other elements. Drawings B.
Buyck.
Figure 8 – Russula glutinosa. Microscopic features of the pileipellis (WRWV 04.1154). A. Hyphal
terminations of the pileus center. B. Hyphal terminations near the pileus margin. C. Surface view of
the pileipellis near the pileus margin showing the inflated terminal cells of hyphal terminations and
the inflations near septa at their base. Scale bar = 10 μm. Drawings B. Buyck.
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Material examined – UNITED STATES OF AMERICA. New Jersey, MORRIS CO., Meadow
woods, in mixed broadleaf forest, 15 July 2002; Buyck 02.227 (PC0125084, holotype of R.
fattoensis); ibid., 10 July 1994, R. M. Fatto 798 (NY02072667), ibid., Mendham town park, in
mixed deciduous forest with Quercus and Fagus, 6 August 1997, R. M. Fatto 1034 (holotype,
NY00253507); ibid., 2 Aug. 1998, R. M. Fatto 1142 (NY02072693); New York, ORANGE CO.,
Greenwood Lake, Jennings Creek, 210 m alt., under Tsuga, 28 July 1996, A. Norarevian coll., R.M.
Fatto 982 (NY00672469); North Carolina: BUNCOMBE CO, near Asheville, NAMA Foray, 17 July
2004, B. Buyck 04-292 (PC0125108); West-Virginia: RALEIGH CO., Grandview Park, near Quercus
alba, Pinus strobus and Rhododendron maximum, 732 m alt., 2 Sept. 2004, William Roody
WRWV 04-1154 (DEWV-F-005518). Tennessee. SEVIER CO., Great Smoky Mts National Park,
Vicinity Gatlinburg, 2450 m alt., in mixed forest with Tsuga, Quercus, 12 July 2004, B. Buyck
04.202 (PC0125107)
Russula glutinosoides Buyck & X.H. Wang, sp. nov. Figs 9, 10, 12d-e, 13c
Mycobank number: MB 833738; Facesoffungi Number: FoF 07372
Etymology – named after its resemblance to R. glutinosa
Differs from R. glutinosa principally by sequence data and its geographical distribution which
is limited to China or possibly larger parts of Asia; morphologically it differs by the more
frequently septate and larger pileocystidia, particularly closer to the pileus context.
Basidiomata single or in very small groups of 2–3 individuals, medium-sized. Pileus 97 mm
diam., quite regular in outline, slightly depressed to plane in the center, firm and quite thick (9 mm
above lamellar attachment); margin smooth, rounded and oriented downward, involute when
young; pellis peeling up to mid-radius, viscous-greasy when humid, shiny when dry, not pruinose,
smooth and continuous, rather evenly coloured over its entire surface, creamish to pale yellow.
Lamellae unequal, multiseriate, being separated by 0–3 lamellulae of different lengths, especially
many very short ones, adnate, rather widely spaced (7–8/cm near the pileus margin), 8 mm high,
brittle, some splitting transversely, narrowing toward the pileus margin, not or rarely forked at
various distances from stipe, sharply delimited from the sterile stipe surface, cream, staining
weakly brownish pink where injured or upon handling; edge even, concolorous. Stipe 48 × 23 mm,
central, gradually narrowing downward, smooth, glabrous, probably white when young, but
yellowish tinged (possibly from handling), very firm and hard, hollowed in the very center
(possibly by animal attack). Context whitish, turning quickly reddish brown to brownish pink
where injured. Odor not remarkable. Taste acrid, but not very strong. Spore print colour not
observed.
Spores very small, ellipsoid to almost lacryform, (4.5)5.0–5.29–5.6(5.8) × (3.3)3.4–3.66–
3.8(4.0) um, Q = (1.35)1.38–1.45–1.52(1.56), with a very low, weakly amyloid ornamentation
made of obtuse, isolated or often aligned, sometimes irregular or comma–shaped warts,
interconnected or fused in short crests, sometimes almost subreticulate; suprahilar plage indistinct,
warted, inamyloid. Basidia 31–43 × 5–6 µm, narrowly clavate, four-spored, sterigmata 4–5.5 × 1
µm. Hymenial gloeocystidia abundant, 63–88 × 5–6.5 µm, narrowly clavate to subcylindrical, often
repeatedly but slightly constricted, sometimes with distinctly more inflated apical part, hardly
emerging, originating from the trama or lower subhymenium, thin-walled; contents moderately
abundant, granular to finely crystalline. Marginal cells small to very small, similar to basidiola or
more irregular in shape, occupying the entire lamellar edge. Subhymenium filamentous to densely
pseudoparenchymatous. Lamellar trama containing oleiferous elements, with numerous
sphaerocytes. Pileipellis in young specimens 200–300 µm thick, orthochromatic to moderately
metachromatic in cresyl blue, vaguely two-layered with a suprapellis consisting of a gelatinous
layer of almost vertical, narrow hyphal terminations, ascending from an ill-defined layer of more
inflated and branching basal cells that may locally develop into a pseudoparenchyma. Hyphal
terminations at the pileus center very slender and narrow, ca. 2 µm wide, often with distinctly
inflated to subglobose, 4–6 µm diam. swellings near the septa or at the very apex, sparsely septate
or branched, with the terminations aligned in a continuous trichoderm, becoming more dispersed
297
with age and toward the pileus margin, where hyphal terminations are usually shorter and slightly
broader, sometimes with more and larger, often repeatedly constricted or globose swellings on
short extremities aggregated in tufts. Pileocystidia of very variable length (from hardly 20 µm up to
several hundreds of µm), mostly 4–10(15) µm diam., difficult to observe unless close to the pileus
margin, dispersed and with sometimes very few contents, some terminal at the very pileus surface,
mostly arising from subpellis or deeper layers, often capitate or with otherwise differentiated apex,
some one-celled, but most being repeatedly septate, subcylindrical, with granular-amorphous,
refringent contents that hardly react to sulfovanillin, orthochromatic in Cresyl blue, showing
distinctly incrusted walls away from the apex; the incrustations yellowish in KOH; continuing as
cystidioid hyphae in subpellis and pileus context underneath. Oleiferous elements present in
context, particular just underneath the subpellis. Clamp connections absent from all parts.
Material examined – China. Yunnan Prov., Nanhua Co., Tujie Town, road from Shuimofang
to Lantanhe, km 9 mark, in mixed forest with Pinus yunnanensis and Quercus trees, 15 Aug 2017,
X.H. Wang 4578/B. Buyck 2017.131 (HKAS 106678, KUN, holotype!; PC0125109, isotype!);
Binchuan Co., Jizushan Town, near Siqian village, 10 Aug. 2011, L.P. Tang 1542 (HKAS 70003,
KUN).
Discussion
Whereas subg. Archaeae has frequently been considered as best potential candidate for most
ancient lineage in the genus, subg. Glutinosae now appears a good candidate for an even more
ancient lineage compared to subg. Archaea as it is sister with high support to a clade composed of
subg. Compactae and Archaeae. The first author has always defended the hypothesis of an origin of
Russula in the tropics, possibly in Africa (Buyck et al. 2018), but the apparently Asian-eastern
North American distribution of subg. Glutinosae now adds support to an alternative hypothesis
suggesting a northern temperate origin of the genus (Looney et al. 2016). Indeed, the new subg.
Glutinosae shares its northern hemisphere distribution with subg. Crassotunicatae Buyck & V.
Hofst., another extremely small and isolated lineage that is also present in Europe and
phylogenetically sister to subg. Heterophyllidiae.
How to morphologically distinguish between the two species that compose this new subgenus
is a serious problem considering there are very few specimens known for each species. Several
macroscopic features, such as stipe dimensions or color of pileus center, seem quite variable and,
under the microscope, we found no significant differences either. Spore ornamentation seems to be
identical for both species, but the holotype of R. glutinosoides has somewhat larger and more
frequently septate pileocystidia compared to the American R. glutinosa. In both species, these
gloeocystidia are unusual in having yellowish incrustations on their surface. Although not rare at
all, neither at the pileus surface nor in the subpellis or pileus context underneath, they are easily
overlooked because they have very thin walls and poorly differentiated contents that hardly react to
reagents; moreover, they break easily when making preparations and, although their apex is often
capitate, so are most terminations of the other hyphae at the surface.
Both R. glutinosa and R. glutinosoides are evidently extremely rare or at least totally ignored
species and not easy to recognize in the field as the similarity with other genera, in particular from
family Hygrophoraceae, can be quite confusing. There exist, for example, no records for either
species in Mushroom Observer (https://mushroomobserver.org), while R. glutinosa accounts for
merely three entries in Mycoportal (http://mycoportal.org/portal/collections), all three being
confirmed here molecularly: one for the R. glutinosa holotype collected in Mendham town (Morris
Co, NJ), one for another R. glutinosa collection studied by R. Fatto from Jennings Creek (Orange
Co, NY), and finally a third specimen from Grandview (Raleigh Co, WV). The present paper has
raised the total number of known collections for R. glutinosa to eight.
We tried to find additional distribution data for subg. Glutinosae by including environmental
sequences when doing nBLAST similarity searches on GenBank and in UNITE with the ITS of the
Chinese R. glutinosoides. The top hit (arranged by max score) is a 97.31% identity with 99%
coverage for the single already deposited sequence of R. glutinosa.
298
Figure 9 – R. glutinosoides. Microscopic features of the hymenium (Holotype). a Basidia and
basidiola. b Marginal cells. c Spores as observed in Melzer’s reagent. d Hymenial gloeocystidia on
lamellar edge. e Hymenial gloeocystidia on lamellar sides. Scale bars = 10 μm, but only 5 μm for
spores. Drawings by B. Buyck.
Figure 10 – R. glutinosoides. Microscopic features of the pileipellis (Holotype). a Pileocystidia. b
Hyphal extremities of the pileus center. c Hyphal extremities of the pileus margin. Scale bar = 10
μm. Drawings B. Buyck.
299
Figure 11 – Russula glutinosa. Field habit. A, B Holotype of R. fattoensis; C, D voucher WRWV
04.1154; E voucher Buyck 04.292 – Pictures copyright of B. Buyck for A, B, E and W. Roody for
C, D
300
Figure 12 – A, B, C Field habit of Russula glutinosa (Buyck 04.202). D, E R. glutinosoides.
(holotype). Photos B. Buyck
301
Figure 13 – Spore ornamentation as seen under Scanning Electron Microscope. A R. glutinosoides
(holotype). B, C R. glutinosa (BB 04.202). Scale bars = 1 μm.
The second top hit, however, shows a 98,56% identity with 93% coverage for an
environmental sequence (AB594932) for a Russula associated with the mycoheterotroph
Monotropastrum humile (Ericaceae) in Japan (Matsuda et al. 2011). None of the other ITS
sequences is more similar than 86% (with query coverage between 99 and 90%). Blasting the ITS
of the American R. glutinosa results in a single significant hit, on the same environmental
sequence, with a similarity of 96.08% (with a similar 93% coverage), suggesting that the Japanese
sequence represents a close relative or local population of R. glutinosoides. Compared to the often
numerous environmental sequences present in GenBank for most of the other newly described
Russula species (Wang et al. 2019a, Adamčík et al. 2019), these BLAST results suggest that both
species are not only rarely producing basidiomes, but also rare below the soil surface. This suggests
that both species should be highly ranked on some kind of red list of ‘endangered’ species of great
phylogenetic interest. In this context, more data are urgently needed concerning their host
association and ecology as, for the moment, collected fruiting bodies come from ‘mixed woods’
and potential host trees include both conifers (pine and hemlock) and deciduous trees (oak and
beech).
When trying to find morphological similarities between subg. Glutinosae and other subgenera
in Russula, the first subgenus that comes to mind is of course subg. Archaeae because of the
similarly small basidiospores. However, the more reticulate spore ornamentation, darker spore
print, frequently septate pileocystidia and the trichodermal suprapellis clearly set subg. Glutinosae
apart from Archaeae. The white spore print mentioned in the original diagnosis of R. fattoensis is
clearly a mistake that we were able to verify on some of our more recent collections. The most
surprising feature for subg. Glutinosae is certainly the septate pileocystidia as this feature is not
known from its sister clade (comprised of subgenera Compactae and Archaeae) nor from any other
subgenus, apart from subg. Russula.
There is another feature that is very unusual within Russula: the apical swellings of hyphal
terminations in the pileipellis. This feature is more or less reminiscent of some species in the crown
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clade, e.g. some members of subsect. Chamaeleontinae (although terminal cells there are more
clavate, rather than just having a very restricted inflation near the very apex or near septa). Apical
inflations exist to a much lesser degree also in a few species of subg. Archaea, such as in R.
camarophylla Romagn. (see Buyck et al. 2003). Most recently, Buyck (in Wang et al. 2019b)
described R. capillaris from Madagascar as a new species in subg. Malodorae (as ‘R. capillaris sp.
ined.’ in Buyck et al. 2018). The latter species is strongly reminiscent of subg. Glutinosae as it is
not only very similar in the field, but it also possesses similar apical swellings, in this case not only
for hyphal terminations in the pileipellis, but also for hymenial gloeocystidia. The morphological
similarity is so striking that we (BB) were convinced, when studying it under the microscope, that it
would turn out to form a monophyletic group with R. glutinosa. Spores, however, are much larger
in R. capillaris and, again, the pileocystidia are not septate, nor in any of the other species in subg.
Malodorae. Therefore, we arrive at a conclusion that the unique combination of unequal lamellae,
cream spore print, subreticulate spores, pileipellis hyphae with capitate terminations, and frequently
septate pileocystidia distinguishes subg. Glutinosae from all other known subgenera in the genus.
As is often the case for very ancient or isolated lineages, performing nBLAST searches can
be quite disorientating considering its fully supported placement that we obtained here in our
multigene phylogenetic analysis. Subgenus Glutinosae offers a classic example illustrating that one
should not blindly trust BLAST results (see Hofstetter et al 2019), as is most frequently done, to
determine the sampling of “closely related” species in phylogenetic approaches. Indeed, the first
100 BLAST hits for nrITS sequences (arranged by max score and excluding environmental
sequences) do not list a single species that belongs to either one of the two subgenera that are most
closely related to it according to our multilocus analysis: viz. subgenera Compactae and Archaeae.
On the contrary, all of the other subgenera show up in the first 100 BLAST results. Since all
produced ITS sequences were identical for all American specimens of R. glutinosa, as well as for
both Chinese specimens of R. glutinosoides, there is nothing wrong with the quality of the obtained
sequences. Yet, the singularity of the ITS region for species in R. subg. Glutinosae probably
explains why R. glutinosa was never part of any previous phylogenetic study in Russula,
notwithstanding that the ITS sequence of R. glutinosa was deposited on GenBank more than 15
years ago.
Performing BLAST searches using protein coding genes appears more accurate towards
suggesting correct affinities for these species, at least nBLAST of RPB2 sequences listed two
members of subg. Archaea as top score results, followed then by species of subgenera Brevipedum,
Crassotunicatae and Heterophyllidiae (Cyanoxanthinae in particular). None of the RPB2 BLAST
results score higher than 84% similarity for an acceptable query coverage. BLAST searches using
RPB1 sequences are different again with nearly all top scores (similarity <93%) comprising species
of subg. Russula. The above illustrates once more the difference between similarity searches and
phylogenetic analyses, the latter being here exclusively based on the unambiguously alignable
regions of the non-coding genes through manual alignment and exclusion of ambiguous regions,
and to strictly coding regions for the protein coding genes through the exclusion of spliceosomal
introns.
The fact that BLAST results frequently point toward species of subg. Brevipedum subsect.
Pallidosporinae Bon, subg. Crassotunicatae and subg. Heterophyllidiae subsect. Cyanoxanthinae,
merits also some attention because all of these groups harbour at least some species with more or
less unequal lamellae, with spores that are smaller than in the majority of Russula species, and all
these groups include at least some representatives with a glutinous or viscose pileipellis (e.g.
several Cyanoxanthinae, R. crassotunicata in subg. Crassotunicatae, R. fuegiana in subg.
Brevipedum).
Acknowledgements
The first author thanks R.H. Petersen and K. Hughes (Knoxville, Tennessee) for inviting him
to the 2004 ATBI in the Smoky Mountains and for producing the ITS sequence for one of the
collected specimens; he also thanks the Fatto family for generous hospitality when collecting in
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New Jersey. The Technical Platform for Electron microscopy of the Paris’ Museum is thanked for
assistance with spore imaging. William Roody is thanked for sharing slides of his collection of R.
glutinosa. Sequencing of R. glutinosa was funded by the national Slovak grant APVV 15-0210.
The 2017 joint field trip of BB and XHW in Yunnan was supported by “Investigation of
Macrofungi of Maguan County” issued by the Ministry of Ecology and Environment, P.R. China,
and the sequencing of R. glutinosoides samples was funded by the CAS Key Laboratory for Plant
Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of
Sciences (project no. LPB201501). Finally, sincere thanks are due to K. Bensch (Mycobank) and
Shaun Pennycook (Landcare Research, NZ) for suggesting the nomenclatural corrections of
subgeneric taxa in Russula.
References
Adamčík S, Caboň M, Looney B, Wisitrassameewong K et al. 2019 – The quest for a globally
comprehensible Russula language. Fungal Diversity 99: 369–449.
https://doi.org/DOI 10.1007/s13225-019-00437-2
Alfaro ME, Zoller S, Lutzoni F. 2003 – Bayes or bootstrap? A simulation study comparing the
performance of Bayesian Markov chain Monte Carlo sampling and bootstrapping in assessing
phylogenetic confidence. Molecular Biology and Evolution 20(2):255–66
Bazzicalupo AL, Buyck B, Saar I, Vauras J et al. 2017 – Troubles with mycorrhizal mushroom
identification where morphological identification lags behind barcode sequence divergence.
Taxon 66(4): 791–810.
Buyck B. 1989 – Valeur taxonomique du bleu de crésyl pour le genre Russula. Bulletin trimestriel
de la Société mycologique de France 105 :1-6.
Buyck B. 1998 – Une révision critique de la sect. Archaeinae (Russula, Russulales). Belgian
Journal of Botany 131 (2): 116–126.
Buyck B. 2004 – Short diagnoses and descriptions of some exotic Russula (Basidiomycotina).
Cryptogamie, Mycologie 25(2): 181–182.
Buyck B, Adamčík S. 2013 – Type studies in Russula subsection Lactarioideae from North
America and a tentative key to North American species. Cryptogamie, Mycologie 34(3):
259–279
Buyck B, Duhem B, Das K, Jayawardena RS, Niveiro N et al. 2017 – Fungal biodiversity Profiles
21–30. Cryptogamie, Mycologie 38(1): 101–146
Buyck B, Heriveau P, Martin P. 2003 – Quelques récoltes récentes de Russula camarophylla
Romagnesi. Bulletin trimestriel de la Société mycologique de France 119: 217–229.
Buyck B, Hofstetter V, Eberhardt U, Verbeken A, Kauff F. 2008 – Walking the thin line between
Russula and Lactarius: the dilemma of Russula subsect Ochricompactae. Fungal Diversity
28:15–40
Buyck B, Zoller S, Hofstetter V. 2018 – Walking the thin line…. Ten years later: the dilemma of
above- versus below-ground features to support phylogenies in the Russulaceae
(Basidiomycota). Fungal Diversity 89(1): 267–292.
Caboň M, Eberhardt U, Looney B, Hampe F et al. 2017 – New insight in Russula subsect.
Rubrinae: phylogeny and the quest for synapomorphic characters. Mycological Progress
16:877–892. https://doi.org/10.1007/s11557-017-1322-0
Doyle JJ, Doyle JL. 1987 – A rapid DNA isolation procedure for small quantities of fresh leaf
tissue. Phytochemical Bulletin 19:11-15.
Fatto RM. 1999 – Three new species of Russula. Mycotaxon 70: 167–175.
Gardes M, Bruns TD. 1993 – ITS primers with enhanced specificity for basidiomycetes -
application to the identification of mycorrhizae and rusts. Molecular Ecology 2:113–118.
https://doi.org/10.1111/j.1365-294X.1993.tb00005.x
304
Heim R. 1938 – Les Lactario–russulés du domaine oriental de Madagascar, essai sur la
classification et la phylogénie des Astérosporales. Prodrome à une flore mycologique de
Madagascar et dépendances I: 196 pp, 4 pl
Hofstetter V, Buyck B, Eyssartier G, Schnée S, Gindro K. 2019 – The unbearable lightness of
sequenced-based identification. Fungal Diversity 96(1): 243–284.
Hongsanan S, Hyde KD, Bahkali AH, Camporesi E et al. 2015 – Fungal Biodiversity Profiles 11–
20. Cryptogamie, Mycologie 36(3):355–380
Kornerup A, Wanscher JH. 1978 – Methuen handbook of color, 3rd Ed., Eyre Methuen Ltd, UK
Looney BP, Ryberg M, Hampe F, Sánchez‐García M, Matheny PB. 2016 – Into and out of the
tropics: global diversification patterns in a hyper‐diverse clade of ectomycorrhizal fungi.
Molecular Ecology 25:630–647.
Matheny PB. 2005 – Improving phylogenetic inference of mushrooms with RPB1 and RPB2
nucleotide sequences (Inocybe; Agaricales). Molecular Phylogenetics and Evolution 35:1–20.
doi:10.1016/j.ympev.2004.11.014
Maddison DR, Maddison WP. 2002 – MacClade: analysis of phylogeny and character evolution,
version 4.05. Sinauer Associates Inc., Sunderland, Massachusetts, USA
Matsuda Y, Okochi S, Katayama T, Yamada A, Ito S. 2011 – Mycorrhizal fungi associated with
Monotropastrum humile (Ericaceae)in central Japan. Mycorrhiza 21(6):569–576.
Miller MA, Pfeiffer W, Schwartz T. 2010 – Creating the CIPRES science gateway for inference of
large phylogenetic trees. In Institute of Electrical and Electronics Engineers (Ed.),
Proceedings of the gateway computing environments workshop (GCE) (pp. 1–8). New
Orleans, LA: IEEE Xplore
Moncalvo JM, Lutzoni FM, Rehner SA, Johnson J, Vilgalys R. 2000 – Phylogenetic relationship of
agaric fungi based on nuclear large subunit ribosomal DNA sequences. Systematic Biology
49(2):278–305. https://doi.org/10.1093/sysbio/49.2.278
Morehouse EA, James TY, Ganley ARD, Vilgalys R et al. 2003 – Multilocus sequences typing
suggests the chytrid pathogen of amphibians is a recently emerged clone. Molecular Ecology
12:395–403
Ondrušková E, Jánošíková Z, Kádasi-Horáková M, Koltay A et al. 2017 – Distribution and
characterization of Dothistroma needle blight pathogens on Pinus mugo in Slovakia.
European Journal of Plant Pathology 148(2):283–294.
https://link.springer.com/article/10.1007/s10658-016-1088-2
Pastirčáková K, Adamčíková K, Pastirčák M, Zach P et al. 2018 – Two blue-stain fungi colonizing
Scots pine (Pinus sylvestris) trees infested by bark beetles in Slovakia, Central Europe.
Biologia 73(11):1053–1066. https://link.springer.com/article/10.2478/s11756-018-0114-6
Rehner SA, Buckley E. 2005 – A Beauveria Phylogeny Inferred from Nuclear ITS and EF1-α
Sequences: Evidence for Cryptic Diversification and Links to Cordyceps Teleomorphs.
Mycologia 97:84–98. http://dx.doi.org/10.3852/mycologia.97.1.84
Stamatakis A. 2008 – A rapid bootstrap algorithm for the RAxML Web servers. Systematic
Biology 57(5):758-71. doi: 10.1080/10635150802429642
Stamatakis A. 2014 – RAxML version 8: a tool for phylogenetic analysis and post-analysis of large
phylogenies. Bioinformatics 30(9):1312–1313
Wang J, Buyck B, Wang XH, Bau T. 2019a – Visiting Russula (Russulaceae, Russulales) with
samples from southwestern China finds one new subsection of Heterophyllidia with two new
species. Mycological Progress 18: 771-784.
Wang XH, Das K, Bera I, Chen YH et al. 2019b – Fungal Biodiversity Profiles 81-90.
Cryptogamie, Mycologie 40(5): 57–95.
White TJ, Bruns T, Taylor LS. 1990 – Amplification and direct sequencing of fungal ribosomal
RNA genes for phylogenetics. In: Innis MA, Gelfand DH, Sninsky JJ, White TJ (eds) PCR
protocols: a guide to methods and application. Academic Press, Inc., San Diego, pp 322–315.
