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Studies in the Basidiodendron caesiocinereum complex (Auriculariales, Basidiomycota)

October 2021
Mycological Progress 20(9):1275 - 1296

DOI:10.1007/s11557-021-01724-6

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CC BY 4.0

Authors:

Viacheslav Spirin

University of Helsinki

Vera Malysheva

Komarov Botanical Institute of the Russ. Acad. Sc. (BIN RAS), St Petersburg

Nathan Schoutteten

University of Hamburg

Ilya Viner

University of Helsinki

Show all 11 authorsHide

Taxonomy of Basidiodendron caesiocinereum complex is revised based on morphological and molecular methods (with the use of nc LSU rDNA, ITS and TEF1 regions). The basidiospore ornamentation is justified as a key morphological character for the species recognition in the group. As redefined here, B. caesiocinereum is an angiosperm-dwelling species with smooth basidiospores. Bourdotia cinerella and B. cinerella var. trachyspora are proved to represent separate species with warted basidiospores; they are reintroduced as Basidiodendron cinerellum and B. trachysporum. Additionally, eight new species related to B. caesiocinereum are described based on material from Eurasia, North America and Africa, and identity of B. spinosum from Oceania is discussed.

continued)

…

Combined phylogenetic ITS + nc LSU rDNA + TEF1 topology from Bayesian analysis showing phylogenetic relationships of the Basidiodendron caesiocinereum complex. GenBank/UNITE or collection numbers (for newly generated sequences) are given for all sequences. Support values (BS/ PP) are given on the branches. Scale bar shows expected changes per site

…

Microscopic structures of Basidiodendron spp. as seen in scanning electron microscope. a, b: B. caesiocinereum (holotype of Corticium caesiocinereum), basidium and basidiospores; c: B. cinerellum (lectotype of Bourdotia cinerella), basidiospores; d: B. groningae (holotype), basidiospores; e: B. spiculosum (holotype), basidiospores; f: B. spinosum (holotype of Sebacina spinosa), basidiospores

…

Basidiospores of Basidiodendron spp. a: B. caesiocinereum (holotype of C. caesiocinereum); b: B. cinerellum (lectotype of Bourdotia cinerella); c: B. glaucum (holotype); d: B. groningae (holotype); e: B. incospicuum (holotype); f: B. mexicanum (holotype); g: B.

…

Microscopic structures of extra-European Basidiodendron spp. with ornamented spores. A: B. inconspicuum (holotype), B: B. mexicanum (holotype), C: B. spiculosum (holotype), D: B. widdringtoniae

…

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https://doi.org/10.1007/s11557-021-01724-6

ORIGINAL ARTICLE

Studies intheBasidiodendron caesiocinereum complex (Auriculariales,

Basidiomycota)

ViacheslavSpirin1 · VeraMalysheva2· NathanSchoutteten3· IlyaViner1· OttoMiettinen1· JenniNordén4·

LeifRyvarden5· HeikkiKotiranta6· AnnemiekeVerbeken3· MichaelWeiß7· Karl‑HenrikLarsson8,9

Received: 28 April 2021 / Revised: 22 June 2021 / Accepted: 23 June 2021

Abstract

Taxonomy of Basidiodendron caesiocinereum complex is revised based on morphological and molecular methods (with the

use of nc LSU rDNA, ITS and TEF1 regions). The basidiospore ornamentation is justiﬁed as a key morphological character

for the species recognition in the group. As redeﬁned here, B. caesiocinereum is an angiosperm-dwelling species with smooth

basidiospores. Bourdotia cinerella and B. cinerella var. trachyspora are proved to represent separate species with warted

basidiospores; they are reintroduced as Basidiodendron cinerellum and B. trachysporum. Additionally, eight new species

related to B. caesiocinereum are described based on material from Eurasia, North America and Africa, and identity of B.

spinosum from Oceania is discussed.

Keywords Basidiospores· Heterobasidiomycetes· Phylogeny· Taxonomy

Introduction

For almost two centuries, the basidiospore features, e.g.

their shape, size, colour and ornamentation, have remained

among the main features for morphological recognition of

the basidiomycetous taxa. Almost all members of the Auric-

ulariales (Basidiomycota) have small or medium-sized, col-

ourless (hyaline), smooth basidiospores and three species

with ornamented (warted or spiny) basidiospores have been

so far detected in the genus Basidiodendron Rick (Wojewoda

1981). Two of them, Basidiodendron asperum (L.S. Olive)

Wojewoda and B. spinosum (L.S. Olive) Wojewoda, are

known from their type localities in Tahiti, while the third

one, B. caesiocinereum (Höhn. & Litsch.) Luck-Allen, was

reported from diﬀerent geographic areas of the world (Wells

and Raitviir 1975).

As re-deﬁned by Luck-Allen (1963), the genus Basidi-

odendron Rick embraces eﬀused wood-inhabiting fungi with

smooth or minutely warted hymenophore, prominent gloe-

ocystidia and longitudinally septate, predominantly four-

celled basidia. It diﬀers from the morphologically similar

genus Bourdotia (Bres.) Bres. & Torrend in having waxy or

arid, non-hygroscopic basidiocarps and on average shorter

basidia devoid of a basal stalk (Luck-Allen 1963, Wells and

Raitviir 1975). Recent phylogenetic studies conﬁrmed that

Basidiodendron and Bourdotia should be treated as separate

Section Editor: Yu-Cheng Dai

* Viacheslav Spirin

viacheslav.spirin@helsinki.ﬁ

1 Finnish Museum ofNatural History, University ofHelsinki,

PO Box7, FI-00014Helsinki, Finland

2 Komarov Botanical Institute RAS, 2 Prof. Popov str.,

St.Petersburg197376, Russia

3 Department ofBiology, Ghent University,

K.L. Ledeganckstraat 35, B-9000Gent, Belgium

4 Norwegian Institute forNature Research, Gaustadalléen 21,

0349Oslo, Norway

5 Department ofBiosciences, University ofOslo, Blindern,

P.O. Box1066, 0316Oslo, Norway

6 Finnish Environment Institute, Latokartanonkaari 11,

00790Helsinki, Finland

7 Steinbeis-Innovationszentrum, Organismische Mykologie

und Mikrobiologie, Vor dem Kreuzberg 17, 72070Tübingen,

Germany

8 Natural History Museum, University ofOslo, Blindern,

P.O. Box1172, 0318Oslo, Norway

9 Gothenburg Global Biodiversity Centre, Post Box461,

40530Gothenburg, Sweden

Mycological Progress (2021) 20:1275–1296

1 3

genera (Weiß and Oberwinkler 2001, Spirin etal. 2020).

While re-describing B. caesiocinereum, Wells (1959) and

Luck-Allen (1963) noted it may have smooth or ornamented

basidiospores. McNabb (1969) and Gilbertson (1974) found

this feature taxonomically insigniﬁcant. On the contrary,

Oberwinkler (1963) designated warted-spored collections

as Bourdotia caesiocinerea (Höhn. & Litsch.) Bourdot &

Galzin var. trachyspora and clearly separated them from

the smooth-spored B. caesiocinerea s. str. Based on nrLSU

sequences, Weiß and Oberwinkler (2001) showed these

taxa are not conspeciﬁc and they belong to Basidiodendron,

although no explicit taxonomic conclusions were proposed.

Finally, Roberts (2001) subsumed the warted-spored speci-

mens of B. caesiocinereum under B. spinosum. To investi-

gate this problem more closely, we examined type specimens

of Corticium caesiocinereum Höhn. & Litsch. (= Basidi-

odendron caesiocinereum) and Sebacina spinosa L.S. Olive

(= B. spinosum), as well as authentic material of Bourdotia

cinerella Bourdot & Galzin (incl. var. trachyspora) (to date,

a synonym of B. caesiocinereum) and a number of B. caesio-

cinereum s. lato specimens from boreal – temperate Eurasia,

North America (USA and Mexico) and Africa (Malawi).

Additionally, a DNA study based on three markers (nc LSU

rDNA, ITS and TEF1) was conducted. Results of this study

are presented below.

Material andmethods

Morphological study

Type specimens and collections from herbaria H, O, GENT,

LE, FH, PC, NY, TAAM, TU, CWU were studied. Her-

barium acronyms are given according to Thiers (2020).

Microscopic routine and terminology follow Spirin etal.

(2020). All measurements were made from microscopic

slides mounted in Cotton Blue, using phase contrast and oil

immersion lens (Leitz Diaplan microscope, ×1250 magniﬁ-

cation). At least 20 basidia, 10–20 gloeocystidia and 20–30

basidiospores were measured for each specimen studied. The

following abbreviations are used in the taxonomic section: L,

mean basidiospore length; W, mean basidiospore width; Q’,

L/W ratio; Q, mean L/W ratio; and n, number of measure-

ments per specimens measured. Advances of phase contrast

illumination versus bright-ﬁeld microscopy are explained

in Stein (1969). For microscopic study, we subjectively

determined an accuracy of measurements as 0.1µm. These

measurements (including those for the basidiospore orna-

mentation elements, i.e. warts or spines) were subsequently

calibrated with the scanning electronic microscope (SEM).

For preparing SEM photos, basidiocarps were coated with

a 25-mm layer of gold-palladium using an Eiko IB-3 sput-

ter coater. Micrographs were taken using JSM-6380LA

microscope at the Moscow State University (Russia) and

JEOL JSM-7100FLV ﬁeld emission microscope at Botanical

Garden Meise (Belgium).

DNA study

In total, 80 specimens were selected for molecular sampling

(Table1). We performed PCR directly from small fragments

of dried basidiocarps (without prior DNA extraction) using

Phire Plant Direct PCR Kit (Thermo Scientiﬁc) according

to the manufacturer’s instructions. DNA extraction of Bel-

gian and Dutch collections was done using the DNeasy Plant

Mini kit (Qiagen).

The following primers were used for both ampliﬁca-

tion and sequencing: the primers ITS1F (Gardes and Bruns

1993) and ITS4 (White etal. 1990) for the nrITS1-5.8S-

ITS2 region, primers EF1-983F and EF1-1567R (Rehner

and Buckley 2005) for a part of the TEF1 region and primers

JS1 (Landvik 1996) and LR5 (Vilgalys and Hester 1990)

for D1-D3 domains of nc LSU rDNA region. PCR prod-

ucts were puriﬁed applying the GeneJET Gel Extraction and

DNA Cleanup Micro Kit (Thermo Scientiﬁc). Sequencing

was performed with an ABI model 3500 Genetic Analyzer

(Applied Biosystems). Raw data were edited and assem-

bled in MEGA 7 (Kumar etal. 2018). Molecular studies

were mostly carried out at the centre for collective use of

scientiﬁc equipment “Cellular and molecular technology of

studying plants and fungi” (Komarov Botanical Institute,

Russian Academy of Sciences, St. Petersburg, Russia) and

the centre for molecular phylogeny and evolution (CeMoFe)

(Ghent University, Belgium).

For this study, 76 ITS, 30 TEF1 and 35 nc LSU rDNA

sequences were generated (Table1). Additionally, 71 ITS

and 61 nc LSU rDNA sequences, including the outgroup,

were retrieved from GenBank and UNITE (www. ncbi.

nlm. nih. gov/ genba nk/; https:// unite. ut. ee/). Sequences

were aligned with the MAFFT version 7 web tool (http://

maﬀt. cbrc. jp/ align ment/ server/) with subsequent manual

processing.

Three datasets were prepared for the present study: (1)

ITS + nc LSU rDNA dataset (1647 characters including

gaps) used to reconstruct a general topology of the Auricu-

lariales, with special focus on Basidiodendron spp.; (2) ITS

+ nc LSU rDNA + TEF1 (1884 characters including gaps);

and (3) ITS only (628 characters including gaps) datasets for

the B. caesiocinereum complex.

Phylogenetic reconstructions were performed with maxi-

mum likelihood (ML) and Bayesian (BI) analyses. Before

the analyses, the best-ﬁt substitution model for the alignment

was estimated based on the Akaike Information Criterion

(AIC) using FindModel web server (http:// www. hiv. lanl.

gov/ conte nt/ seque nce/ ﬁndm odel/ ﬁndm odel. html). “K80

plus Gamma” model was chosen for ITS dataset, and “GTR

Mycological Progress (2021) 20:1275–1296

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Table 1 DNA sequences generated for the present study

Species Specimen/herbarium Country (ISO code) Host GenBank /UNITE sequence numbers

nrITS nrLSU TEF1

Basidiodendron

caesiocinereum NS 18-172(GENT) BE Fagus sylvatica MW139272 - -

B. caesiocinereum NS 18-226(GENT) BE F. sylvatica MW139267 - -

B. caesiocinereum NS 18-625(GENT) BE F. sylvatica MW139268 - -

B. caesiocinereum NS 18-902 (GENT) BE F. sylvatica MW139269 - -

B. caesiocinereum NS 18-925 (GENT) BE F. sylvatica MW139270 - -

B. caesiocinereum NS 18-1050 (GENT) BE F. sylvatica MW139266 - -

B. caesiocinereum NS 18-1051 (GENT) BE F. sylvatica MW139271 - -

B. caesiocinereum OM 10608(H) CN Populus sp. (?) MW136071 - -

B. caesiocinereum VS 13663 (H) IT Corylus avellana MW136105 MW136140 MW187110

B. caesiocinereum VS 11764(O) NO Ulmus glabra MW136082 - -

B. caesiocinereum VS 11776 (O) NO Betula pubescens MW136101 MW136136 MW187106

B. caesiocinereum VS 12536 (O) NO Tilia cordata MW136069 - MW187084

B. caesiocinereum VS 12500 (O) NO C. avellana MW136061 - -

B. caesiocinereum VS 12502 (O) NO U. glabra MW136084 - MW187095

B. caesiocinereum VS 12504 (O) NO U. glabra MW136065 - MW187082

B. caesiocinereum VS 12511 (O) NO U. glabra MW136083 - MW187094

B. caesiocinereum VS 12515 (O) NO U. glabra MW136100 MW136135 MW187105

B. caesiocinereum VS 12465 (O) NO U. glabra MW136102 MW136137 MW187107

B. caesiocinereum VS 11115 (O) NO Alnus incana MW136103 MW136138 MW187108

B. caesiocinereum SS 901 (O) NO Picea abies MW259231 - -

B. caesiocinereum HK 26428 (H) RU-KRA Alnus hirsuta MW136072 - MW187085

B. cinerellum VS 13485 (H) BE Pinus sylvestris MW136088 MW136125 MW187097

B. cinerellum VS 12337 (TU) EE P. sylvestris UDB0754270 - -

B. cinerellum VS 12350 (TU) EE C. avellana UDB0754279 - -

B. cinerellum VS 13681 (H) IT P. abies MW136086 MW136123 MW187096

B. cinerellum VS 11188 (O) NO A. incana MW136104 MW136139 MW187109

B. cinerellum VS 12449 (O) NO U. glabra MW136064 - MW187081

B. cinerellum VS 13317 (H) SI Pinus mugo MW136097 MW136131 MW187102

B. cinerellum VS 13275 (H) SI P. mugo MW136093 MW136130 MW187101

B. eyrei ENZ 13-100 (GENT) NL P. abies MW139273 - -

B. eyrei ENZ 18-101 (GENT) NL decayed wood MW139274 - -

B. eyrei ENZ 18-103 (GENT) NL decayed wood MW139275 - -

B. eyrei NS 19-411 (GENT) NL decayed wood MW139277 - -

B. glaucum VS 11750 (O) NO A. incana MW136085 - -

B. glaucum JN 9815 (O) NO Picea abies MW259227 - -

B. glaucum JN 9920 (O) NO P. abies MW259234 - -

B. glaucum JN 9858 (O) NO P. abies MW259226 - -

B. glaucum SS 370 (O) NO P. abies MW136079 MW136120 MW187091

B. glaucum JN 9683 (O) NO P. abies MW259233 - -

B. glaucum JN 9079 (O) NO P. abies MW259232 - -

B. glaucum JN 9080 (O) NO P. abies MW259228 - -

B. glaucum SS 11 (O) NO P. abies MW259229 - -

B. glaucum SS 140 (O) NO P. abies MW259235 - -

B. glaucum SS 144 (O) NO P. abies MW136070 - -

B. glaucum SS 863 (O) NO P. abies MW136078 MW136119 MW187090

B. glaucum VS 7890 (H) RU-KHA Picea ajanensis MW136063 - -

B. groningae GVA 20-040 (GENT) BE rotten wood MW139280 - -

Mycological Progress (2021) 20:1275–1296 1277

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plus Gamma” model was chosen for nrITS + nc LSU rDNA

+ TEF1 and ITS + nc LSU rDNA datasets.

Maximum likelihood analysis was run on RAxML serv-

ers, v.0.9.0 (Kozlov etal. 2019) with 1000 rapid bootstrap

replicates. Bayesian analyses was performed with MrBayes

3.2.5 software (Ronquist etal. 2012), for two independent

runs, each with 5 million generations (for ITS + nc LSU

rDNA + TEF1 dataset) and 10 million generations (for ITS

and ITS + nc LSU rDNA datasets), under described mod-

els and four chains with sampling every 100 generations.

To check for convergence of MCMC analyses and to get

estimates of the posterior distribution of parameter values

Tracer v1.6 was used (Rambaut etal. 2014). We accepted the

result where the ESS (eﬀective sample size) was above 200

and the PSRF (potential scale reduction factor) was close

to 1.

The outgroup choice for the order-level phylogeny (Sis-

totrema brinkmannii (Bres.) J. Erikss., Cantharellales) was

guided by the current JGI Basidiomycota tree ((https://

mycoc osm. jgi. doe. gov/ mycoc osm/ speci es- tree/ tree;_

FJDxL? organ ism= basid iomyc ota) where Cantharellales

were recovered close to Auriculariales and Sebacinales. ITS,

nc LSU rDNA and TEF1 sequences of Bourdotia, the sister

genus of Basidiodendron, were selected as outgroups for the

species-level analyses of the B. caesiocinereum complex.

Newly generated sequences have been deposited in Gen-

Bank with corresponding accession numbers (Table1).

Alignments have been deposited in TreeBASE (S27231).

Table 1 (continued)

Species Specimen/herbarium Country (ISO code) Host GenBank /UNITE sequence numbers

nrITS nrLSU TEF1

B. groningae ENZ 18-001 (GENT) NL conifer MW139278 MW136483 -

B. groningae ENZ 19-073 (GENT) NL conifer MW139276 MW136482 -

B. groningae NS 18-1325 (GENT) NL Hippophae rhamnoides MW139265 - -

B. inconspicuum VS 8171 (H) US-WA Thuja plicata MW136098 MW136132 MW187103

B. mexicanum LR 23131 (O) MX Pinus patula MW136068 - -

B. robenae OM 16910.2 (H) US-NY hardwood MW270998 MW271001 -

B. robenae OM 19650 (H) US-NY hardwood MW270997 MW271000 -

B. spiculosum LR 23324 (O) MX Cyathea sp. MW136076 MW136117 MW187088

B. trachysporum TU 112986 EE decayed wood UDB016299 - -

B. trachysporum OM 22962.2 (H) FI P. abies MW136096 - -

B. trachysporum ENZ 20-005 (GENT) NL P. sylvestris MW139281 - -

B. trachysporum VS 11111 (O) NO P. abies MW136089 MW136126 -

B. trachysporum VS 12528 (O) NO P. abies MW136067 MW136113 MW187083

B. trachysporum VS 11801 (O) NO P. abies MW136091 MW136129 MW187100

B. trachysporum VS 11803 (O) NO P. abies MW136090 MW136127 MW187098

B. trachysporum VS 12508 (O) NO P. abies MW136081 MW136122 MW187093

B. trachysporum JN 9601 (O) NO P. abies MW259230 MW136134 -

B. trachysporum SS 608 (O) NO P. abies MW136062 MW136111 -

B. trachysporum HK 26387 (H) RU-KRA Pinus sibirica MW136087 MW136124 -

B. trachysporum VS 11886 (H) RU-LEN P. abies MW152419 MW136128 MW187099

B. trachysporum VS 9188a (H) RU-NIZ P. sylvestris MW136080 MW136121 MW187092

B. trachysporum VS 9481 (H) RU-NIZ P. sylvestris MW136074 MW136115 MW187086

B. trachysporum VS 9483 (H) RU-NIZ U. glabra MW136077 MW136118 MW187089

B. trachysporum HK 29616 (H) RU-ZAB conifer MW270996 MW270999 -

B. trachysporum VS 12548 (H) SI Larix decidua MW136099 MW136133 MW187104

B. trachysporum VS 12623 (H) SI P. abies MW136095 - -

B. trachysporum VS 13147 (H) SI P. abies MW136092 - -

B. trachysporum AS 72(CWU) UA Quercus robur MW136094 - -

B. trachysporum VS 8262 (H) US-WA Pseudotsuga menziesii MW136060 - -

B. trachysporum VS 8740 (H) US-WA Abies lasiocarpa MW136075 MW136116 MW187087

B. walleynii WR 3081 (GENT) BE Q. robur MW139279 - -

B. walleynii VS 9697 (H) RU-NIZ Q. robur MW136066 MW136112 -

B. widdringtoniae LR 11307a (O) MW Widdringtonia whytei MW136073 MW136114 -

Mycological Progress (2021) 20:1275–1296

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Results

ITS + nc LSU rDNA dataset

The overall topologies of the ML and BI trees were nearly

identical (Fig.1). They uncovered all B. caesiocinereum

s. lato specimens involved in the analyses in one strongly

supported clade (bs =100, pp =1) with B. luteogriseum

Rick (the generic type of Basidiodendron) and members

of the B. eyrei complex (as deﬁned by Spirin etal. 2020).

Therefore, we interpreted all these taxa as belonging to

one genus, Basidiodendron. In turn, the Basidiodendron

clade was split into four strongly supported subclades.

Two of them covered the Basidiodendron eyrei complex

and contained fourteen species with smooth, ellipsoid or

globose, usually small basidiospores. They all were dealt

with in our previous publication (Spirin etal. 2020). Two

remaining subclades encompassed the B. caesiocinereum

complex. The larger subclade (designated in Fig.1 as B.

caesiocinereum group) contained sequences of specimens

morphologically identical to the type material of B. cae-

siocinereum (smooth-spored) and B. caesiocinereum var.

trachysporum (warted-spored). According to our results,

these taxa should be accepted as two separate species; as

a consequence, B. caesiocinereum var. trachysporum is

raised to the species level. Additionally, ﬁve more lineages

were detected in the B. caesiocinereum group. These are

introduced as new species below. Two of them (B. glau-

cum and B. robenae) are smooth-spored, two species (B.

inconspicuum and B. walleynii) have warted basidiospores,

and in one species (B. widdringtoniae) the spore wall bears

spines. The smaller subclade (labelled as Basidiodendron

cinerellum group, Fig.1) contained sequences of specimens

identical to a lectotype of Bourdotia cinerella; the latter

species is redescribed and combined in Basidiodendron

below. Alongside B. cinerellum with warted spores, three

new species (introduced as B. groningae, B. mexicanum and

B. spinulosum) with spiny basidiospores were uncovered

in the B. cinerellum group. Rather high variability of ITS

sequences of some species (in particular, B. caesiocinereum

s. str. and B. trachysporum) prompted us to investigate their

identity with the use of an additional marker.

ITS + nc LSU rDNA + TEF1 dataset

The ﬁnal alignment contained 1884 characters (including

gaps). The overall topologies of the ML and BI trees were

nearly identical and in a good correspondence with the ITS +

LSU phylogeny (Fig.2). Both B. caesiocinereum s. str. and B.

trachysporum lineages are strongly supported and therefore

interpreted by us as representing single species each.

ITS dataset

Twenty additional environmental ITS sequences related to B.

caesiocinereum complex were retrieved from GenBank and

UNITE and used in the phylogenetic analyses (Supplement).

Seven of them belonged to B. trachysporum and conﬁrmed

this species is widespread in temperate—boreal forests

of Eurasia and North America. Basidiodendron caesioci-

nereum, B. cinerellum and B. walleynii were represented by

three, two and one environmental sequences, respectively.

Seven remaining sequences potentially represent four more

species in the B. caesiocinereum complex: two from Canada

(British Columbia) (KP889384, KP889562), one from tem-

perate Europe (Austria) (JF519252, JF519305) and possi-

bly one more represented by sequences from UK, Estonia

and Alaska (AF504871, KF297103, UDB0141409). How-

ever, we could not connect these sequences with available

herbarium material, and therefore their identity remains

unresolved.

The morphology-based species identiﬁcation in the B.

caesiocinereum complex mainly relies on the presence and

character of basidiospore ornamentation. As stated under

“Material and methods,” phase contrast illumination and

Cotton Blue as a mountant are compulsory for this investi-

gation. Of twelve species treated below, three species have

completely smooth basidiospores and in nine species they

are ornamented (Figs.3, 4). Among the latter ones, four

species possess warted and ﬁve have spiny outgrowths on

the spore wall. Other morphological traits should also be

considered for a correct species recognition. In particular,

three species with warted basidiospores occurring in Europe

(B. cinerellum, B. trachysporum and B. walleynii) are distin-

guishable due to diﬀerently looking basidiocarps and gloeo-

cystidia, as well as speciﬁc arrangement of hymenial cells.

Diﬀerentiating characters of B. caesiocinereum and related

species are summarized in Table2. Sequenced collections

are marked by asterisk.

Taxonomy

Basidiodendron caesiocinereum (Höhn. & Litsch.) Luck-

Allen, Canadian J. Bot. 41: 1036, 1963. – Figs.3, 4, 5 and 6

≡ Corticium caesiocinereum Höhn. & Litsch., Sitzungsb.

Kaiserl. Akad. Wissenschaften, Math.-Naturw. Klasse Abt.

1, 117: 1116, 1908. Holotype. Germany. Nordrhein-West-

falen: Steinfurt, Lengerich, rotten hardwood, 1908 Brink-

mann (FH 00304795, studied).

Basidiocarps eﬀused, smooth, ﬁrst waxy, pruinose or

somewhat gelatinized, semitranslucent, greyish, then com-

pact, greyish-bluish, older basidiocarps with a faint ochra-

ceous-brownish tint, 0.02–0.03 (0.05) mm thick, up 3 cm in

widest dimension, margin gradually thinning-out. Hyphal

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structure monomitic, hyphae clamped; subicular hyphae

thin- or slightly thick-walled, subparallel, (2) 3–4 (5.5) μm

diam, subhymenial hyphae thin-walled, easily collapsing,

ascending or interwoven, 2–3 (3.5) μm diam. Gloeocystidia

rather abundant to rare, tapering, slightly projecting, hyaline

to yellowish, (13) 14–40 (41) × (4) 4.2–9.4 (10.0) μm (n

= 86/11). Basidia four-celled, ovoid to suburniform, (11.8)

12.2–24.2 (26.8) × (7.0) 7.2–11.4 (12.3) μm (n = 339/20),

occasionally with a distinct stalk-like base up to 10 × 3–5

μm, sterigmata gradually tapering, up to 15 × 2.5–3 μm;

involucres poorly developed. Basidiospores smooth, thin-

walled, compressed-subglobose or globose, (5.0) 5.1–7.8

(8.3) × (5.2) 5.3–8.1 (8.8) μm (n = 780/26), L = 5.57–6.93,

W = 5.97–7.28, Q’ = (0.8) 0.9–1.0, Q = 0.93–1.00, apiculus

prominent, regular, sometimes slightly asymmetric, up to 2

× 2 μm.

Distribution and ecology. Europe (Belgium, Estonia, Fin-

land, Germany, Italy, Norway), Asia (China, Russia – Sibe-

ria); almost exclusively on rotten wood of deciduous trees,

as a rule in excessively humid habitats.

Remarks. Höhnel and Litschauer (1908) described C.

caesiocinereum based on a single collection from Ger-

many. They overlooked inner septation of basidia as well

as the presence of cystidia, and this was a reason for them

to assign the new species to the genus Corticium s. lato.

Bourdot and Galzin (1927) restudied the type material of C.

caesiocinereum and found that it has gloeocystidia and four-

celled basidia. They concluded that C. caesiocinereum is an

older name for Bourdotia cinerella Bourdot & Galzin. This

viewpoint has persisted in the literature until the present

day. However, we argue below that B. cinerella represents a

warted-spored taxon, while the type specimen of C. caesioc-

inereum has smooth basidiospores. Therefore, the synonymy

of C. caesiocinereum and B. cinerella should be abandoned.

As redeﬁned here, B. caesiocinereum is most similar to B.

glaucum. The two species are best separated by their ecolog-

ical preferences. Basidiodendron glaucum is a northern spe-

cies almost exclusively restricted to coniferous wood, while

B. caesiocinereum is connected to angiosperm hosts, mainly

in inundated habitats. However, B. glaucum may acciden-

tally occur on deciduous trees, and one sequenced collection

of B. caesiocinereum came from spruce. In these cases, B.

caesiocinereum can be distinguished from B. glaucum due

to longer basidia occasionally provided with a long stalk-like

base. Basidiospores of B. caesiocinereum are on average

larger than in B. glaucum, although their variation ranges

are strongly overlapping. The distribution areas of both B.

caesiocinereum and B. glaucum stretch along the northern

part of Eurasia. No veriﬁed records of these species exist

from North America. See B. robenae for further comments.

Specimens examined. Belgium. Vlaams-Brabant:

Hoeilaart, Zoniënwoud, Kersselaerspleyn, Fagus sylvatica,

X.2018 Schoutteten 18-172*, 18-226*, 18-625*, 18-902*,

18-925*, 18-1050*, 18-1051* (GENT). China. Jilin:

Antu Co., Huang Song Pu, Populus sp. (?), 28.VIII.2005

Miettinen 10608* (H). Finland. Varsinaissuomi: Bromarv,

Rilax, deciduous wood, 13.X.2000 Saarenoksa 12100 (H).

Uusimaa: Helsinki, Myllypuro – Puotinharju, Betula sp.,

3.IX.1989 Saarenoksa 18789 (H), Vanhakaupunki, Alnus

incana, 10.IX.1989 Saarenoksa 22889 (H), hardwood,

18.IX.1998 Saarenoksa 17598 (H), Veräjämäki, Salix caprea

(?), 19–21.X.2011 Miettinen 14910.1, 14934.2 (H), Betula

sp., 25.X.2019 Miettinen 22920.1 (H); Porvoo, Stensböle,

S. caprea, 1.XI.1990 Kotiranta 9337 (H); Sipoo, Lilla

Kummelberget Nat. Res., Populus tremula, 29.IX.2010

Kotiranta 22735 (H). Enontekiön Lappi: Enontekiö,

Kilpisjärvi, Betula pubescens spp. tortuosa, 2.IX.1983

Kotiranta 4745a (H). Germany. Bavaria: Bad Hindelang,

Hinterstein, strongly decayed deciduous wood, 20.IX.1995

Weiß 1995-320* (M.W.). Italy. Lombardy: Varese, Valganna,

San Gemolo, Corylus avellana, 14.X.2019 Spirin 13663*

(H). Norway. Vest-Agder: Lyngdal, Skoland, Ulmus glabra,

1.XI.2017 Spirin 11764* (O, H), rotten wood, 1.XI.2017

Larsson 17730, 17733, 17735, 17737, 17751 (O); Mandal,

Uføra, Betula pubescens, 2.XI.2017 Spirin 11776* (O),

C. avellana, 2.XI.2017 Spirin 11780 (O). Aust-Agder:

Grimstad, Sæveli, C. avellana, 2.XI.2017 Spirin 11788

(O). Vestfold: Larvik, Jordstøyp i Kvelde, Tilia cordata,

30.IX.2018 Spirin 12536* (O), U. glabra, 30.IX.2018 Spirin

12538, 12539, 12542 (O), Vemannsås, U. glabra, 30.IX.2018

Spirin 12523 (O). Telemark: Bamble, Rognsheia, A. incana,

3.XI.2017 Spirin 11799 (O); Nome, Mørkvasslia, A. incana,

25.X.2016 Spirin 11187 (O), Picea abies, 16.X.2011

Svantesson 901* (O F253623). Buskerud: Lier, Asdøljuvet,

A. incana, 29.IX.2018 Spirin 12515* (O), C. avellana,

29.IX.2018 Spirin 12500* (O), U. glabra, 29.IX.2018 Spirin

12502*, 12504*, 12511* (O). Akershus: Asker, Esvika,

Acer platanoides, 28.IX.2018 Spirin 12462 (O), U. glabra,

28.IX.2018 Spirin 12465* (O); Baerum, Kjaglidalen, A.

incana, 16.IX.2016 Spirin 11115*, 11121 (O), C. avellana,

16.IX.2016 Spirin 11123, 11126 (O), S. caprea, 16.IX.2016

Spirin 11129 (O). Oppland: Nord-Fron, Liadalane, A. incana,

12.IX.2016 Spirin 11044 (O), 29.IX.2017 Spirin 11636,

11649 (O), rotten wood, 29.IX.2017 Larsson 17631 (O);

Sel, Sagåa, S. caprea, 13.IX.2016 Spirin 11069 (O). Møre og

Romsdal: Nesset, Eikesdalen, A. incana, 27.IX.2017 Spirin

11610 (O), rotten wood, 27–28.IX.2017 Larsson 17548,

17558 (O). Russia. Krasnoyarsk Reg.: Turukhansk Dist.,

Lebed’, Alnus hirsuta, 23.VIII.2013 Kotiranta 26428* (H).

Fig. 1 Combined phylogenetic ITS + nc LSU rDNA topology from

Bayesian analysis showing main lineages within the Auriculariales.

Sequences generated for this study are indicated in bold. GenBank/

UNITE or collection numbers (for newly generated sequences) are

given for all sequences. Support values (BS/PP) are given above the

branches. Scale bar shows expected changes per site

◂

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Basidiodendron cinerellum (Bourdot & Galzin) Spirin

& V. Malysheva, comb. nov. – Figs.3, 4, 5 and 7

MB 838719

≡ Bourdotia cinerella Bourdot & Galzin, Bull. Soc.

Mycol. France 36: 71, 1920. Lectotype (selected here,

MBT395945). France. Aveyron: Causse Noir, Pinus sp.,

20.XI.1913 Galzin 14526 (herb. Bourdot 12419) (PC

0706677).

Basidiocarps effused, smooth, first waxy, pruinose-

reticulate, greyish, then gelatinized, continuous, dirty-grey

to pale ochraceous or brownish, occasionally tuberculate,

often with irregularly scattered craters, 0.01–0.05 mm thick,

covering a few cm, margin gradually thinning-out. Hyphal

structure monomitic, hyphae clamped, glued together;

subicular hyphae thin-walled, subparallel, 2.5–4 μm diam,

subhymenial hyphae thin-walled, ascending or interwoven,

occasionally twisted, 1.5–3 μm diam, basidia-bearing

hyphae distinct in older parts of hymenium, slightly thick-

walled, up to 12 × 2–3.5 μm. Gloeocystidia abundant,

more or less clearly tapering, slightly projecting, hyaline

or yellowish to brownish, (13.5) 14–34 (35) × (3.4) 3.7–8.0

(9.0) μm (n = 75/8), solitary or in groups of 2–5. Basidia

four-celled, ovoid to broadly suburniform, (8.8) 8.9–16.0

(17.0) × (6.3) 7.0–10.2 (10.3) μm (n = 70/7), sterigmata

gradually tapering, up to 10 × 1.5–2 μm; involucres well-

developed, often totally covering basidial cells (except

sterigmata); basidia in mature specimens embedded in

gelatinous matrix and glued together in large groups.

Basidiospores warted, thin- or slightly thick-walled (wall

up to 0.2 μm thick), compressed-subglobose or globose,

(4.8–) 4.9–7.2 (–7.6) × (5.1–) 5.2–7.7 (–7.8) μm (n =

330/11), L = 5.48–6.43, W = 5.85–6.77, Q’ = 0.9–1.0, Q =

0.94–0.97, apiculus prominent, regular, sometimes slightly

asymmetric, up to 1.5 × 1.2 μm.

Fig. 2 Combined phyloge-

netic ITS + nc LSU rDNA +

TEF1 topology from Bayesian

analysis showing phylogenetic

relationships of the Basidioden-

dron caesiocinereum complex.

GenBank/UNITE or collection

numbers (for newly generated

sequences) are given for all

sequences. Support values (BS/

PP) are given on the branches.

Scale bar shows expected

changes per site

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Distribution and ecology. Europe (Belgium, Estonia, Fin-

land, France, Germany, Italy, Norway, North-West Russia,

Slovenia, Sweden); on tough, often still corticated branches

and fallen logs in various stages of decay, predominantly of

conifers.

Remarks. Bourdot and Maire (1920) introduced B.

cinerella from a large set of specimens collected in the

southern part of France. They described it as having smooth

spherical basidiospores and later considered it a synonym

of C. caesiocinereum. However, B. cinerella has remained

untypiﬁed, and therefore its actual relation to C. caesioci-

nereum was obscure. We studied all (in total 29) specimens

stored in Bourdot’s herbarium (PC), which were labelled by

him as ‘Sebacina (Bourdotia) cinerella’. Of them, two col-

lections (Bourdot 40882 and 9047) belong to B. cinereum

(Bres.) Luck-Allen s. lato, a species with cylindrical-ellip-

soid spores; they do not ﬁt to the protologue and cannot be

used for typiﬁcation. The rest of the specimens have globose

spores, in good accordance with the original description, but

they are warted, not smooth. Among them, two specimens

represent Bourdotia cinerella var. trachyspora described

seven years later (Bourdot and Galzin 1927) and considered

here as a separate species. They certainly were not the main

source for the B. cinerella description. Twelve remaining

specimens were collected from coniferous (Pinus) and thir-

teen were from angiosperm hosts. However, both decidu-

ous trees and conifers were mentioned as substrates in the

protologue of B. cinerella, and therefore the host indication

alone is insuﬃcient for understanding the original idea of the

species. Fortunately, Bourdot and Galzin provided a good

description of macroscopic traits of B. cinerella: basidio-

carps were described as ‘whitish, whitish-grey, often glanc-

ing, pale ochraceous and crustaceous when old’ (‘blanchâ-

tre, blanc-gris souvent brillant, subocracé et crustacé sur le

vieux’ – Bourdot and Galzin 1920: 71). These indications ﬁt

the pine-dwelling specimens and preclude collections from

Fig. 3 Microscopic struc-

tures of Basidiodendron spp.

as seen in scanning electron

microscope. a, b: B. caesioci-

nereum (holotype of Corticium

caesiocinereum), basidium and

basidiospores; c: B. cinerel-

lum (lectotype of Bourdotia

cinerella), basidiospores;

d: B. groningae (holotype),

basidiospores; e: B. spiculosum

(holotype), basidiospores; f: B.

spinosum (holotype of Sebacina

spinosa), basidiospores

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angiosperm hosts with arid, opaque basidiocarps. We assign

the latter ones to a new species B. walleynii and select the

best-developed specimen from Pinus (Galzin 14526, herb.

Bourdot 12419) as a lectotype of B. cinerella.

Basidiodendron cinerellum is one of three species with

warted basidiospores distributed in Europe. The most strik-

ing microscopic feature, diﬀerentiating B. cinerellum from

two other species (i.e., B. trachysporum and B. walleynii),

is the presence of a cyanophilous gelatinous matter covering

basidial cells. In juvenile specimens, this matter is visible

at least in some basidia as an essential (1–2μm) thickening

of the basidial wall. In mature, and especially in senescent

basidiocarps, the gelatinous matrix covers basidia up to the

very top and glues them together in large, easily detectable

groups. Moreover, basidiocarps of B. cinerellum often have

dirty-greyish or ochraceous-brownish tints and, at least in

some parts, they are more or less clearly gelatinized. In con-

trast, basidiocarps of B. walleynii remain arid and normally

pale, while in B. trachysporum they are usually very thin,

constantly whitish-greyish and occasionally gelatinized only

when old. No signs of hymenial gelatinous matter so charac-

teristic for B. cinerellum were detected in B. trachysporum

or B. walleynii.

Basidiodendron cinerellum and B. trachysporum inhabit

mostly coniferous hosts and sometimes occur in the same

habitats. Our data suggest, however, that they may have

quite diﬀerent ecological specialization. Basidiodendron

cinerellum seemingly prefers tough, often still corticated

wood—mainly thick, still hanging or just fallen branches or

small- to medium-sized logs. In turn, Basidiodendron tra-

chysporum mostly occurs on well-decomposed wood, often

on rotten logs lying on the ground or inside old stumps,

Fig. 4 Basidiospores of Basidiodendron spp. a: B. caesiocinereum

(holotype of C. caesiocinereum); b: B. cinerellum (lectotype of Bour-

dotia cinerella); c: B. glaucum (holotype); d: B. groningae (holo-

type); e: B. incospicuum (holotype); f: B. mexicanum (holotype); g: B.

robenae (holotype); h: B. spiculosum (holotype); i: B. trachysporum

(Spirin 12548); j: B. walleynii (holotype); k: B. widdringtoniae (holo-

type). Scale bar = 10 µm

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although several records were made from small corticated

coniferous branches.

Specimens examined. Belgium. Namur: Philippeville,

Viroinval, Fondry des Chiens, Pinus sylvestris, 11.X.2019

Spirin 13485*, 13494 (H). Estonia. Viljandimaa: Tipu,

Kikepera, P. sylvestris, 16.IX.2018 Spirin 12337* (H,

TU114809), Lemmjõe, C. avellana, 17.IX.2018 Spirin

12350* (H, TU114820). Finland. Varsinaissuomi: Lohja,

Lohjansaari, P. abies, 28.VIII.2003 Kotiranta 19980 (H);

Tammisaari, Tenhola, P. abies, 1.IX.2004 Kotiranta 20450

(H). Uusimaa: Helsinki, Kumpula, P. abies, 16.IX.2001

Saarenoksa 04201 (H), Mölylä, P. abies, 4.XI.2017 Miettinen

21459 (H), Veräjämäki, P. abies, 30.X.2019 Viner 2019-

195 (H), P. sylvestris, 3.VI.2019 Spirin 12543 (H); Sipoo:

Rörstrand, P. abies, 22.IX.2009 Miettinen 14005 (H); Vantaa,

Vestra, dead Fomitopsis pinicola on P. abies, 10.V.2014 Spirin

6850 (H). Etelä-Häme: Hämeenlinna, Ahvenaistenjärvi, P.

abies, 22.IX.2016 Miettinen 20402 (H), Kotinen, P. abies,

25.IX.2014 Spirin 8099 (H). Etelä-Karjala: Virolahti, Klamila,

decorticated board (old house), 5.VI.2010 Kotiranta 22704a

(H). Inarin Lappi: Utsjoki, Kevo, Juniperus communis,

20.IX.2009 Kotiranta 23123 (H). France. Aveyron: Causse

Noir, Pinus sp., 3.XI.1911 Galzin 10147 (herb. Bourdot

9059) (PC 0706674), Galzin 10190 (herb. Bourdot 9061)

(PC 0084210), 20.XI.1913 Galzin 14514 (herb. Bourdot

13962) (PC 0706665), Galzin 14520 (herb. Bourdot 13963)

(PC 0706676), Galzin 14537 (herb. Bourdot 13964) (PC

0706673), 30.XI.1913 Galzin 14775 (herb. Bourdot 13966)

(PC 0706675), 17.V.1915 Galzin 17703 (herb. Bourdot 20187)

(PC 0706678), 5.XII.1915 Galzin 18879 (herb. Bourdot

15695) (PC 0706666), Galzin 18906 (herb. Bourdot 18566)

(PC 0706660), Galzin 18919 (herb. Bourdot 15733) (PC

0706681), 16.V.1919 Galzin 24592 (herb. Bourdot 26851) (PC

0706682). Germany. Bavaria: Wertach, Jungholz, decayed P.

Table 2 Geographic, ecological and morphological traits in Basidiodendron caesiocinereum complex

Species Geographic distribution Host Basidia Basidiospores

B. caesiocinereum Eurasia, temperate – hemibo-

real Angiosperms 12–24 × 7–11.5 μm, exposed smooth,

5.1–7.8 × 5.3–8.1 μm,

Q = 0.93–1.00

B. cinerellum Europe, temperate – boreal Mostly

gymnosperms 9–16 × 7–10 μm, glued in

groups warted,

4.9–7.2 × 5.2–7.7 μm,

Q = 0.94–0.97

B. glaucum Eurasia, boreal Gymnosperms (predominantly

Picea)10–14.5 × 7.5–10.5 μm,

exposed smooth,

5.1–6.8 × 5.2–7.0 μm,

Q = 0.96–0.98

B. groningae Europe, temperate Gymnosperms and angio-

sperms 13–18 × 9–12 μm, exposed spiny,

6.0–7.9 × 6.2–8.2 μm,

Q = 0.95–0.96

B. inconspicuum North America (North West),

temperate Gymnosperms (Thuja) 10–13 × 7–9 μm, exposed warted,

5.0–6.2 × 5.2–6.5 μm,

Q = 0.95

B. mexicanum North America, temperate Gymnosperms (Pinus) 12–15.5 × 9.5–12 μm, exposed spiny,

5.9–7.3 × 6.1–7.4 μm,

Q = 0.96

B. robenae North America, temperate Angiosperms 12–18 × 7–9 μm, exposed smooth,

5.1–6.4 × 5.2–6.9 μm,

Q = 0.94–0.96

B. spiculosum North America, subtropical Fern remains 15–24 × 10–12 μm, exposed spiny,

6.9–8.2 × 7.1–8.9 μm,

Q = 0.96

B. spinosum Oceania (Tahiti), tropical Rotten wood 9–10 × 6–7.5 μm, exposed spiny,

4.6–5.2 × 4.8–5.8 μm,

Q = 0.96

B. trachysporum Eurasia and North America

(North-West), temperate –

boreal

Mostly gymnosperms 8.5–16 × 7–11 μm, exposed warted,

4.8–7.4 × 5.0–7.8 μm,

Q = 0.94–0.98

B. walleynii Europe, temperate Angiosperms (mostly Castanea

and Quercus)11–15.5 × 7–11 μm, exposed warted,

5.1–7.0 × 5.3–7.2 μm,

Q = 0.96–0.98

B. widdringtoniae South Africa, subtropical Gymnosperms (Widdringtonia) 11.5–14 × 8–11 μm, glued in

groups spiny,

5.9–6.8 × 6.1–7.1 μm,

Q = 0.96

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Fig. 5 Basidiocarps of Basidi-

odendron spp. a: B. caesioci-

nereum (Spirin 11764); b: B.

cinerellum (Spirin 13317); c: B.

trachysporum (Spirin 11801); d:

B. walleynii (Bourdot 19447).

Scale bar = 1 cm

Fig. 6 Microscopic structures of

smooth-spored Basidiodendron

spp. A: B. caesiocinereum (hol-

otype of C. caesiocinereum),

B: B. glaucum (holotype), C: B.

robenae (holotype); hc – hyme-

nial cells, sh – subicular hyphae.

Scale bar = 10 µm

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abies, 8.X.1996 Weiß 1996-393* (M.W.). Italy. Lombardy:

Varese, Bedero Valcuvia, Marteghetta, P. abies, 14.X.2019

Spirin 13681* (H), P. sylvestris, 14.X.2019 Spirin 13692 (H).

Norway. Telemark: Bamble, Rognsheia, P. abies and dead

Phellinus ferrugineofuscus, 3.XI.2017 Larsson 17829 (O);

Nome, Mørkvasslia, A. incana, 25.X.2016 Spirin 11188*

(O). Akershus: Asker, Stokkerelva at Åstaddammen, U.

glabra, 28.IX.2018 Spirin 12449* (O); Baerum, Kjaglidalen,

P. abies, 4.V.2016 Spirin 10019 (O). Oppland: Lunner,

Rinilhaugen Nat. Res., P. abies, 17.IX.2016 Spirin 11144

(O); Sel, Sagåa Nat. Res., P. abies, 13.IX.2016 Spirin 11059

(O). Russia. Leningrad Reg.: Boksitogorsk Dist., Anisimovo,

P. abies, 15.VII.2014 Spirin 7004 (H), Vozhani, P. abies,

2.X.2016 Spirin 11168 (H); Kirishi Dist., Klinkovo, P. abies,

7.VIII.2019 Spirin 12872 (H); Podporozhie Dist., Vazhinka,

P. abies, 16.IX.2017 Spirin 11405 (H). Yamalo-Nenets

Fig. 7 Microscopic structures of European Basidiodendron spp. with

ornamented spores. A: B. cinerellum (Spirin 12337), B: B. gronin-

gae (holotype), C: B. trachysporum (Spirin 11111), D: B. walleynii

(hymenial cells from holotype, gloeocystidia from Walleyn 3081);

ba – basidia embedded in gelatinous matrix, gl – gloeocystidia, hc –

hymenial cells, sh – subicular hyphae. Scale bar = 10 µm

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Autonomous Dist.: Priuralsky Dist., Sob’, Picea obovata,

11.VIII.1969 Parmasto (TAAM 053842). Slovenia. Gorenjska:

Kranjska Gora, Vršič, Pinus mugo, 5.VI.2019 Spirin 12576

(H), 27.IX.2019 Spirin 13317*, 13325, 13333, 13338, 13344

(H); Bohinj, Lipanca, L. decidua, 26.IX.2019 Spirin 13290,

13303 (H), 29.VII.2020 Spirin 13945 (H), P. abies, 6.VI.2019

Spirin 12594, 12613, 12626 (H), 26.IX.2019 Spirin 13229,

13237 (H), P. mugo, 26.IX.2019 Spirin 13275*, 13281, 13287,

13293 (H), Mrežce, P. abies, 26.IX.2019 Spirin 13221 (H),

Mrzli Studenec, P. abies, 27.VII.2020 Spirin 13879 (H), Ravne

v Bohinju, Abies alba, 28.VII.2020 Spirin 13888 (H), Studor,

P. abies, 27.VII.2020 Spirin 13852 (H); Mojstrana, Triglavska

Bistrica, P. abies, 28.IX.2019 Spirin 13418, 13422, 13471 (H).

Sweden. Kalmar: Vimmerby, Norra Kvill, P. abies, 27.X.2010

J. Nordén 7879 (O). Örebro: Lekeberg, Ugglehöjden, P. abies,

13.X.2010 J. Nordén 7561 (O).

Basidiodendron glaucum Spirin & K.H. Larss., sp.

nov. – Figs.4 and 6

MB 838720

Holotype. Norway. Nord-Trøndelag: Snåsa, Blåella,

64.2939N 13.029E, Picea abies (decorticated log),

28.IX.2011 J. Nordén 9683* (O F-248006, isotype – H).

Etymology: Glaucus (Lat., adj.) – bluish-grey, in refer-

ence to the basidiocarp’s colour.

Basidiocarps eﬀused, smooth, ﬁrst waxy, pruinose, then

continuous, arid, greyish, 0.02–0.06 (0.1) mm thick, up 6

cm in widest dimension, margin gradually thinning-out.

Hyphal structure monomitic, hyphae clamped; subicular

hyphae thin-walled, subparallel, 2–3 μm diam, subhymenial

hyphae thin-walled, easily collapsing, ascending or interwo-

ven, 1.5–2 (2.5) μm diam. Gloeocystidia rather rare, taper-

ing, slightly projecting, hyaline to yellowish, (14) 14.5–34.0

(38.0) × (3.7) 4.0–8.2 (9.0) μm (n = 30/3). Basidia four-

celled, ovoid to broadly suburniform, (10.1) 10.2–14.3

(14.8) × (7.0) 7.7–10.3 (11.0) μm (n = 62/6), sterigmata

gradually tapering, up to 13 × 2.5–3 μm; involucres poorly

developed. Basidiospores smooth, thin-walled, compressed-

subglobose or globose, (5.0) 5.1–6.8 (7.0) × (5.0) 5.2–7.0

(7.2) μm (n = 270/9), L = 5.53–6.24, W = 5.67–6.37, Q’ =

0.9–1.0 (1.1), Q = 0.96–0.98, apiculus prominent, usually

slightly asymmetric, up to 2 × 1.8 μm.

Distribution and ecology. Europe (France, Norway,

North-West Russia, Sweden), Asia (Russian Far East);

almost exclusively on rotten wood of conifers.

Remarks. Basidiodendron glaucum is distributed in boreal-

subalpine coniferous forests of Eurasia. It seems to occur

mostly in old-growth communities with abundant wood rem-

nants. Basidiodendron globisporum Spirin & V. Malysheva

has the same ecological preferences. It can be distinguished

from B. glaucum by the smaller basidia (9–12 × 7–9 μm) and

basidiospores (4.6–5.8 × 4.8–5.9 μm, L = 4.95–5.15, W =

5.10–5.33) with a less prominent apiculus (Spirin etal. 2020).

Diﬀerences between B. glaucum and the look-alike B. caesio-

cinereum are listed above. Basidiodendron robenae is mor-

phologically almost indistinguishable from B. glaucum but

it was detected only on angiosperm hosts in North America.

Specimens examined (paratypes). France. Vosges: Saint-

Dié-des-Vosges, Plainfaing, Col du Bonhomme, A. alba,

12.X.2019 Spirin 13539 (H). Norway. Vest-Agder: Lyngdal,

Fladstad, A. incana, 1.XI.2017 Spirin 11750* (O). Akershus:

Nannestad, Rudskampen, P. abies, 10.X.2011 J. Nordén 9815*

(O F-248007). Telemark: Drangedal, P. abies, 18.X.2011 J.

Nordén 9920* (O F253676); Nome, Mørkvasslia, P. abies,

16.X.2011 J. Nordén 9858* (O F253666); Sandalslia, P.

abies, 13.X.2011 Svantesson 863* (O). Akershus: Nannestad,

8.X.2011 J. Nordén 9760 (O). Sør-Trøndelag: Selbu, Råndalen,

P. abies, 19–20.IX.2011 J. Nordén 9313, 9326, 9339 (O),

Svantesson 351 (O); Tydal, Hilmo, P. abies, 22.IX.2011

Svantesson 370* (O), 23.IX.2011 J. Nordén 9573 (O). Nord-

Trøndelag: Snåsa, Blåella, P. abies, 27.IX.2011 J. Nordén

9605 (O), 28.IX.2011 J. Nordén 9678, 9680 (O). Nordland:

Hattelldal, Nordlia, P. abies, 9.IX.2011 J. Nordén 9079* (O

F253604), J. Nordén 9080* (O F253638); Grane, Litltuva,

P. abies, 5–6.IX.2011 Svantesson 10 (O), Svantesson 11* (O

F253609), Svantesson 52 (O), Svantesson 140* (O F253677),

Svantesson 141, 144* (O). Russia. Khabarovsk Reg.:

Verkhnebureinskii Dist., Dublikan Nat. Res., Picea ajanensis,

23.VIII.2014 Spirin 7890* (H 7028622). Leningrad Reg.:

Kirishi Dist., Shariya, P. abies, 10.VIII.2019 Spirin 12922

(H). Sweden. Västra Götaland: Strömstad, Hästeskede, P.

abies, 31.X.2011 J. Nordén 10037 (O). Västerbotten: Lycksele,

Altarliden, P. abies, 29.IX.2010 J. Nordén 7152 (O).

Basidiodendron groningae Schoutteten & Spirin, sp.

nov. – Figs.3, 4 and 7

MB 838721

Holotype. Netherlands. Groningen: Lauwersoog, Ballast-

plaatbos, 53.402N 6.213E, Hippophae rhamnoides (dry cor-

ticated branch), 10.XI.2018 Schoutteten 18-1325* (GENT,

isotype – H).

Etymology: Groninga (Lat., noun) – a Latin name of Gro-

ningen, the type locality.

Basidiocarps effused, smooth, first waxy, pruinose-

reticulate, greyish, then continuous, greyish to pale

ochraceous, 0.02–0.04 mm thick, covering a few mm, in some

portions slightly gelatinized, margin gradually thinning-out.

Hyphal structure monomitic, hyphae clamped; subicular

hyphae thin- or slightly thick-walled, interwoven, 2–3 μm

diam, subhymenial hyphae thin- to slightly thick-walled,

ascending or interwoven, 1.5–2 μm diam. Gloeocystidia

abundant, distinctly tapering, slightly projecting, hyaline to

yellowish, (14) 18–34 (41) × (4.0) 4.1–7.0 (7.5) μm (n =

20/1), solitary or in groups of 2–7. Hyphidia not observed.

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Basidia normally four-celled, ovoid to broadly suburniform,

(12.8) 12.9–17.8 (18.2) × (8.4) 9.0–12.0 (12.2) μm (n =

30/2), sterigmata gradually tapering, up to 14 × 2.5–3

μm; some basidia obliquely or even transversally septate,

1–2-sterigmatic, occasionally pleural; involucres indistinct.

Basidiospores spiny (spines up to 0.3–0.6 μm long), thin-

walled or with slightly thickened (up to 0.3 μm) walls,

compressed-subglobose or globose, (5.9) 6–7.9 (9.1) × (6.1)

6.2–8.2 (9.4) μm (n = 90/3), L = 6.35–7.14, W = 6.68–7.40,

Q’ = 0.9–1.0, Q = 0.95–0.96, apiculus prominent, regular or

eccentric, sometimes slightly asymmetric, up to 3 × 1.8 μm.

Distribution and ecology. Europe (Belgium, Netherlands);

dead wood of unidentiﬁed conifers and deciduous trees (Hip-

pophae rhamnoides).

Remarks. Basidiodendron groningae is the only species

with spiny basidiospores so far detected in Europe. It was

collected three times around Groningen in the Netherlands and

once in Belgium, but its actual distribution is unknown. Four

other species with spiny spores dealt with in this paper were

found in North America (B. mexicanum, B. spiculosum), Africa

(B. widdringtoniae) and Oceania (B. spinosum). In the type

specimen of B. groningae, basidia occasionally bear oblique

or even transversal septa, and then only one or two apical cells

produce sterigmata. This feature illustrates morphological

ﬂexibility of basidial cells most likely caused by environmental

conditions and seems to have no taxonomic importance.

Specimens examined (paratypes). Belgium. Antwerpen:

Boeckhout, Den Turck, rotten wood, 6.II.2020 Van Autgaerden

20-040* (GENT). Netherlands. Groningen: Lauwersoogbos,

fallen corticated coniferous branch, 11.XI.2018 Enzlin

18-001* (GENT); Oude Pekela, Pekelderbos, fallen corticated

coniferous branch, 24.X.2019 Enzlin 19-073* (GENT).

Basidiodendron inconspicuum Spirin & V. Malysheva,

sp. nov. – Figs.4 and 8

MB 838722

Holotype. USA. Washington: Clallam Co., Willoughby

Creek, 47.8218N 124.1983W, Thuja plicata (very rotten

decorticated log), 7.X.2014 Spirin 8171* (H, isotype – LE).

Etymology: Inconspicuus (Lat., adj.) – inconspicuous,

in reference to the hardly detectable basidiocarps of the

species.

Basidiocarps eﬀused, smooth, waxy, pruinose-reticulate,

whitish or greyish, 0.01–0.02 mm thick, covering a few

mm, hardly detectable. Hyphal structure monomitic, hyphae

clamped; subicular hyphae slightly thick-walled, subparallel,

2–3 μm diam, subhymenial hyphae thin- or slightly thick-

walled, ascending or interwoven, 1.5–3 μm diam. Gloeocystidia

abundant, tapering, slightly projecting, hyaline to yellowish,

(12) 13–27 (37) × (3.6) 3.8–7.8 (8.3) μm (n = 20/1), solitary.

Basidia four-celled, ovoid to broadly suburniform, (9.8)

10.2–13.2 (13.7) × (6.8) 7.0–8.8 (9.2) μm (n = 20/1), sterigmata

gradually tapering, up to 8 × 1.5 μm; involucres normally

poorly developed, well-visible in senescent hymenium only.

Basidiospores minutely warted, thin-walled, compressed-

subglobose or globose, (4.8) 5.0–6.2 × (5.1) 5.2–6.5 (6.7) μm (n

= 30/1), L = 5.49, W = 5.76, Q’ = 0.9–1.0, Q = 0.95, apiculus

regular, sometimes slightly asymmetric, up to 1.2 × 1.5 μm.

Distribution and ecology. So far known from the type

locality; strongly decayed wood of conifers (Thuja plicata).

Remarks. Basidiodendron inconspicuum produces very

thin, hardly detectable basidiocarps consisting of two–three

subparallel basal hyphae and sparse subhymenial hyphae

bearing hymenial cells. Morphologically, it is most simi-

lar to B. trachysporum. The latter species has on average

larger basidiospores with more pronounced (up to 0.2–0.3

μm long) warts. In turn, the basidiospore ornamentation of

B. inconspicuum is seen only under phase contrast as tiny

(0.1–0.2μm long) warts regularly arranged on the spore

surface. Phylogenetically, B. inconspicuum is more closely

related to the smooth-spored B. caesiocinereum than to B.

trachysporum.

Basidiodendron mexicanum Spirin & V. Malysheva,

sp. nov. – Figs.4 and 8

MB 838723

Holotype. Mexico. Vera Cruz: Cofre de Perote, Mpio

de Xico, El Revolcadera, 19.473N 97.154W, Pinus patula

(rotten decorticated log), 18.IX.1985 Ryvarden 23131* (O,

isotypes – H, LE).

Etymology: Mexicanus (Lat., adj.) – after Mexico, where

the species was collected.

Basidiocarps eﬀused, smooth, ﬁrst waxy, pruinose, whit-

ish or greyish, then continuous, greyish to pale ochraceous,

arid, 0.02–0.03 mm thick, covering a few cm, occasionally

gelatinized and semitranslucent, margin gradually thinning-

out. Hyphal structure monomitic, hyphae clamped; subicular

hyphae slightly thick-walled, subparallel, 2–3.5 μm diam,

subhymenial hyphae slightly thick-walled, ascending or

interwoven, frequently anastomosing, 2–3.5 μm diam. Gloe-

ocystidia abundant, distinctly tapering, slightly projecting,

hyaline to yellowish or rarely brownish, (11) 17–34 (35) ×

(4.2) 4.3–6.2 (7.0) μm (n = 20/1), solitary or in groups of

2–3. Hyphidia occasionally present, mostly simple, 1–1.5

μm in diam. (apical part), projecting up to 15 μm. Basidia

four-celled, ovoid to broadly suburniform, (11.5) 11.8–15.7

(16.0) × (9.2) 9.7–12.2 (12.3) μm (n = 20/1), sterigmata

gradually tapering, up to 15 × 2–2.5 μm; involucres well-

developed, often totally covering basidial cells (except

sterigmata). Basidiospores spiny (spines up to 0.3–0.4 μm

long), thin-walled, compressed-subglobose or globose, (5.8)

5.9–7.3 (7.6) × 6.1–7.4 (7.8) μm (n = 30/1), L = 6.45, W =

6.69, Q’ = 0.9–1.0, Q = 0.96, apiculus prominent, regular,

sometimes slightly asymmetric, up to 2 × 1.8 μm.

Mycological Progress (2021) 20:1275–1296 1289

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Distribution and ecology. So far known from the type local-

ity; decorticated coniferous wood in a highland forest.

Remarks. Basidiodendron mexicanum is one of the spe-

cies with spiny basidiospores introduced here. It diﬀers from

B. spiculosum, also found in Mexico, in having thinner basidi-

ocarps, shorter gloeocystidia and smaller basidiospores, as well

as by the presence of hyphidia. Phylogenetically, B. mexicanum

is closely related to B. groningae so far detected only in Europe

(Figs.1, 2). The latter species possesses basidiospores with more

pronounced spines than in B. mexicanum, and it lacks hyphidia.

ITS sequences of these species show 2.7–3.9% distance (the

infraspeciﬁc diﬀerences within B. groningae are under 1.6%).

Morphologically, B. mexicanum is most similar to B. widdring-

toniae (see remarks under the latter species). Basidiodendron

widdringtoniae is so far known from Malawi only and phylo-

genetically closer to B. walleynii than to B. mexicanum or B.

spiculosum.

Basidiodendron robenae Spirin & Miettinen, sp. nov.

– Figs.4 and 6

MB 838725

Holotype: USA, New York, Essex Co., Arbutus Lake,

43.9836N 74.2354W, fallen angiosperm tree, 16.IX.2013 Miet-

tinen 16910.2* (H).

Etymology: After Robena Luck-Allen, the ﬁrst monographer

of the genus Basidiodendron.

Basidiocarps eﬀused, smooth, waxy, continuous, pale ochra-

ceous to greyish, 0.02–0.05 mm thick, covering a few cm in wid-

est dimension, margin gradually thinning-out. Hyphal structure

monomitic, hyphae clamped; subicular hyphae slightly thick-

walled, subparallel, occasionally glued together, 2–3.5 μm

diam, subhymenial hyphae thin- to slightly thick-walled, glued

together, ascending or interwoven, 2–3 μm diam, basidia-bear-

ing hyphae distinct in older parts of hymenium, slightly thick-

walled, up to 10 × 2.5–3 μm. Gloeocystidia abundant, slightly or

Fig. 8 Microscopic structures of extra-European Basidiodendron spp.

with ornamented spores. A: B. inconspicuum (holotype), B: B. mexi-

canum (holotype), C: B. spiculosum (holotype), D: B. widdringtoniae

(holotype); ba – basidia embedded in gelatinous matrix, gl – gloeo-

cystidia, hc – hymenial cells, sh – subicular hyphae. Scale bar = 10

µm

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distinctly tapering, projecting, hyaline to yellowish, (15) 16–32

(33) × (5.2) 5.6–8.8 (9.3) μm (n = 36/2). Basidia four-celled,

ovoid to suburniform, (11.0) 12.2–18.2 (18.8) × (7.0) 7.1–9.2

(10.4) μm (n = 40/2), sterigmata gradually tapering, up to 10 ×

1.5–2.5 μm; involucres occurring in senescent hymenium, cov-

ering basidia up to the very top. Basidiospores smooth, thin- or

slightly thick-walled, compressed-subglobose or globose, (5.0)

5.1–6.4 × (5.1) 5.2–6.9 (7.2) μm (n = 90/3), L = 5.69–5.72, W

= 5.95–6.03, Q’ = 0.9–1.0, Q = 0.94–0.96, apiculus prominent,

usually regular, up to 1.2 × 1.8 μm.

Distribution and ecology. North America (Canada – Ontario,

USA – New York, Tennessee); rotten wood of deciduous trees.

Remarks. Basidiodendron robenae is a smooth-spored spe-

cies distributed in the north-eastern part of North America. It

is morphologically almost indistinguishable from the Eurasian

species B. glaucum. In addition to separated distribution areas,

these species have diﬀerent substrate preferences: B. robenae

has been detected on angiosperm hosts while B. glaucum occurs

almost exclusively on coniferous wood, mainly on Picea spp.

Specimens examined (paratypes). Canada. Ontario: York

Co., Nashville, Fagus grandifolia, 22.X.1955 Cain (H ex TRTC

31661). USA. Tennessee: Cocke Co., Cosby Creek, fallen

angiosperm tree, 2.X.2015 Miettinen 19650* (H), Betula sp.,

2.X.2015 Miettinen 19655 (H), Sevier Co., Ramsey Cascade

Trail, Quercus sp., 30.IX.2015 Miettinen 19562 (H).

Basidiodendron spiculosum Spirin & Ryvarden, sp. nov.

– Figs.3, 4 and 8

MB 838726

Holotype. Mexico. Vera Cruz: Xalapa, Botanical Gar-

den, 19.514N 96.947W, Cyathea sp. (dry stem), 22.IX.1985

Ryvarden 23324* (O, isotypes – H, LE).

Etymology: Spiculosus (Lat., adj.) – spiculate, in reference

to the basidiospore ornamentation.

Basidiocarps effused, smooth, waxy, pruinose-reticulate,

whitish or cream-coloured, then pale ochraceous, 0.02–0.04 mm

thick, covering a few cm, margin gradually thinning-out. Hyphal

structure monomitic, hyphae clamped; subicular hyphae slightly

thick-walled, subparallel, 2–3 μm diam, subhymenial hyphae

thin- or slightly thick-walled, interwoven, 1.5–2.5 μm diam,

quickly collapsing. Gloeocystidia abundant, tapering or tubular-

clavate, slightly projecting, hyaline to yellowish or brownish, (27)

28–51 (55) × (6.3) 6.8–10.0 (11.3) μm (n = 20/1), solitary of in

groups of 2–3. Basidia four-celled, ovoid to broadly suburniform,

(14.2) 14.8–24.2 (25.0) × (9.6) 9.8–12.0 (12.8) μm (n = 24/1),

sterigmata gradually tapering, up to 10 × 2–2.5 μm; involucres

well-developed, often covering basidial cells up to the middle

part. Basidiospores spiny (spines up to 0.3–0.4 μm long), thin-

or slightly thick-walled (wall up to 0.3 μm thick), compressed-

subglobose or globose, (6.8) 6.9–8.2 (8.8) × (7.0) 7.1–8.9 (9.0)

μm (n = 30/1), L = 7.62, W = 7.95, Q’ = 0.9–1.0, Q = 0.96,

apiculus prominent, regular, sometimes slightly asymmetric, up

to 2 × 2 μm.

Distribution and ecology. So far known from the type local-

ity; dry stem of a tree fern.

Remarks. Of the species dealt with herein, B. spiculosum

is most similar to B. mexicanum; their diﬀerences are listed

under the latter species. It seems the diversity of the spinose-

spored Basidiodendron spp. in North America is not exhausted

by two species only. Kisimova-Horovitz etal. (1997) reported

B. spinosum from Costa Rica, and their description indicates

the presence of one more, still unnamed species with spinose

basidiospores.

Basidiodendron spinosum (L.S. Olive) Wojewoda, Mala

Flora Grzybów 2: 91, 1981. – Fig.3

≡ Sebacina spinosa L.S. Olive, Bull. Torrey Bot. Club 85: 27,

1958. Holotype. French Polynesia. Tahiti: Fautaua Valley, very

rotten wood, 3.VII.1956 Olive T398 (NY 01293275, studied).

Basidiocarps eﬀused, smooth, waxy, pruinose-reticulate,

whitish or greyish, 0.03–0.05 mm thick, covering a few cm,

margin gradually thinning-out. Hyphal structure monomitic,

hyphae clamped, densely arranged; subicular hyphae thin- to

slightly thick-walled, subparallel, 1.5–2.5 μm diam, subhymenial

hyphae thin- to slightly thick-walled, ascending or interwoven,

1.5–2.5 μm diam. Gloeocystidia tapering or clavate, slightly

projecting, hyaline or yellowish, 22–25 ×5.5–10 μm. Basidia

four-celled, ovoid to broadly suburniform, widely collapsed, ca.

9–10 × 6–7.5 μm, sterigmata gradually tapering, up to 9 × 2–2.5

μm; involucres indistinct. Basidiospores spiny (spines up to 0.6

μm long), thick-walled (wall up to 0.7 μm thick), compressed-

subglobose or globose, 4.6–5.2 × 4.8–5.8 μm (n = 30/1), L =

5.00, W = 5.22, Q’ = 0.9–1.0, Q = 0.96, apiculus prominent,

regular, sometimes somewhat asymmetric, up to 1.2 × 0.8 μm.

Distribution and ecology. So far known from the type local-

ity; rotten wood of an unidentiﬁed tree.

Remarks. The only available material of this species is repre-

sented by the type specimen from Tahiti. Basidiodendron spino-

sum diﬀers from other species of the B. caesiocinereum complex

in having very prominent and densely arranged spines on the

spore surface and clearly thick-walled basidiospores. Newly

collected and sequenced specimens from the type locality are

needed for clarifying phylogenetic relationships of B. spinosum

with other representatives of the genus.

Basidiodendron trachysporum (Bourdot & Galzin) Spirin,

M. Weiß & Miettinen, comb. nov. – Figs.4, 5 and 7

MB 838727

≡ Bourdotia cinerella var. trachyspora Bourdot & Galzin,

Hyménomycètes de France: 50, 1927. Lectotype (selected

here, MBT395946). France. Aveyron: Causse Noir, Pinus sp.,

8.V.1911 Galzin 9106 (herb. Bourdot 9073) (PC).

Mycological Progress (2021) 20:1275–1296 1291

1 3

Basidiocarps eﬀused, smooth or indistinctly tuberculate,

ﬁrst waxy, pruinose, whitish or greyish, then continuous,

greyish to pale ochraceous, arid, 0.01–0.03 mm thick,

covering a few cm, occasionally gelatinized, semitranslucent

and then almost invisible by a naked eye, margin gradually

thinning-out. Hyphal structure monomitic, hyphae clamped;

subicular hyphae thin- or slightly thick-walled, subparallel,

(1.5) 2–3.5 μm diam, subhymenial hyphae thin- or slightly

thick-walled, ascending or interwoven, 1.5–2.5 (–3) μm diam,

basidia-bearing hyphae distinct in older parts of hymenium,

slightly thick-walled, up to 15 × 2.5–3 μm. Gloeocystidia

abundant, tapering, slightly projecting, hyaline to yellowish,

(12) 13–45 (60) × (2.8) 3.0–7.8 (8) μm (n = 129/15), solitary

or in groups of 2–6. Basidia four-celled, ovoid to broadly

suburniform, (8.2) 8.3–15.8 (16.0) × (6.7) 6.9–11.0 (11.2)

μm (n = 198/17), sterigmata gradually tapering, up to 10 ×

1.5–2.5 μm; involucres normally poorly developed, well-

visible in senescent basidiocarps only. Basidiospores warted,

thin-walled, compressed-subglobose or globose, 4.8–7.4 (7.8)

× (4.9) 5.0–7.8 (7.9) μm (n = 590/20), L = 5.26–6.58, W =

5.46–6.79, Q’ = 0.9–1.0, Q = 0.94–0.98, apiculus prominent,

regular, sometimes slightly asymmetric, up to 2 × 1.8 μm.

Distribution and ecology. Europe (Estonia, Finland, France,

Netherlands, Norway, Russia, Slovenia, Sweden, Ukraine),

Asia (Russia – Siberia and Far East), North America (USA

– Washington); predominantly strongly decayed wood, mostly

of conifers.

Remarks. This species was initially introduced as

a warted-spored variety of B. cinerella (Bourdot and

Galzin 1927), while the latter was erroneously described

as a smooth-spored species (see discussion under B.

cinerellum). The single authentic specimen labelled by

Bourdot as ‘Sebacina (Bourdotia) cinerella f. trachyspora’

is an extensive collection in good condition, and it is

designated here as a lectotype. Morphological diﬀerences

of B. trachysporum from B. cinerellum are listed under

the latter species. Another similarly looking European

species, B. walleynii, occurs on deciduous hosts and has

thicker basidiocarps and diﬀerently shaped, wider and

clearly projecting cystidia. Basidiodendron trachysporum

is certainly the most common species of the genus in the

middle- and north-boreal forests of North Europe.

The morphological variability of B. trachysporum

deserves a closer look. In particular, one specimen

collected in the North-American North-West (Spirin 8262)

has unusually large basidia, 15–23 × 11.5–14.5 μm, and

basidiospores, (8.6) 9.0–11.2 (11.7) × (9.1) 9.2–11.9 (12.3)

μm (n = 30/1), L = 9.69, W = 10.00, Q’ = 0.9–1.0 (1.1),

Q = 0.97. However, the ITS sequence of this collection

does not show any signiﬁcant diﬀerences versus other ITS

sequences of B. trachysporum, and our attempts to sequence

additional markers were unsuccessful. For now, we treat the

specimen under B. trachysporum.

Specimens examined. Estonia. Valgamaa: Otepää, Kääriku,

decorticated decayed wood, 10.IX.2012 Põldmaa (TU

112986*), Välkjärve, P. tremula, 15.IX.2015 Spirin 9848 (H).

Finland. Ahvenanmaa: Geta, Getabergen, P. abies, 24.X.2001

Kotiranta 19148 (H), Snäkö, small wooden planks, 24.X.2001

Saarenoksa 18601 (H); Lumparland, Skag, J. communis,

23.X.2007 Kotiranta 22098 (H). Varsinaissuomi: Salo, Orjan-

perä, P. sylvestris, 10.V.2010 Kotiranta 22663 (H); Tammisaari,

Tenhola, P. abies, 16.IX.2008 Kotiranta 22418 (H). Uusimaa:

Helsinki, Kumpula, coniferous wood, 13.XI.1999 Saarenoksa

04699 (H), Patola, A. incana, 26.X.2011 Miettinen 14981.3

(H), Veräjämäki, P. abies, 26.IX.2018 Miettinen 21815 (H),

1.XI.2019 Miettinen 22962.2* (H), P. sylvestris, 20.X.2019

Miettinen 22899, 22906 (H), Viikki, P. abies, 1.X.2000 Saare-

noksa 07600 (H), 6.XI.2019 Viner 2019-215 (H); Inkoo, Som-

marö Nat. Res., P. sylvestris (old collapsed house), 22.V.2010

Kotiranta 22695 (H); Kirkkonummi, Sundsberg, P. sylvestris,

17.V.2005 Kotiranta 21261 (H), 20.X.2012 Miettinen 15789.2

(H); Porvoo, Stensböle, P. abies, 1.XI.1990 Kotiranta 9354 (H).

Etelä-Häme: Hämeenlinna, Kotinen, P. abies, 25.IX.2014 Spirin

8102 (H); Luhanka, Lempää, J. communis, 6.X.2010 Kotiranta

22796, 22805 (H); Padasjoki: Koivukannonsuo, P. abies, 6–7.

IX.2003 Miettinen 7508.1 (H). France. Aveyron: L’Hospitalet,

Pinus sp., 26.XI.1916 Galzin 21134 (herb. Bourdot 20188) (PC

0706680); St. Sernin, Cerasus sp. and debris, 3.VI.1909 Gal-

zin 4250 (herb. Bourdot 20185) (PC 0706658). Netherlands.

Groningen: Hoogezand, P. sylvestris, 7.II.2020 Enzlin 20-005*

(GENT). Norway. Vestfold: Larvik, Jordstøyp i Kvelde, P.

abies (old collapsed building), 15.IX.2016 Spirin 11111* (O),

Vemannsås, P. abies, 30.IX.2018 Spirin 12528*, 12530 (O).

Telemark: Bamble, Rognsheia, P. abies, 3.XI.2017 Spirin

11801*, 11803* (O), rotten wood, 3.XI.2017 Larsson 17796

(O); Nome, Mørkvasslia, P. abies, 25.X.2016 Spirin 11196

(O). Akershus: Nannestad, P. abies, 8.X.2011 J. Nordén 9770

(O). Buskerud: Lier, Asdøljuvet, P. abies, 29.IX.2018 Spirin

12508* (O), Stokkerinden, P. abies, 29.IX.2018 Larsson 17910

(O). Hedmark: Åmot, Gravrusttjern, hardwood, 2.IX.1978 Høg-

holen 832/78 (O 165333). Østfold: Aremark, Tjøstøl, P. abies,

24.X.2011 Svantesson 1008 (O). Sør-Trøndelag: Tydal, Hilmo,

P. abies, 22.IX.2011 Svantesson 368 (O). Nord-Trøndelag:

Snåsa, Blåfjella, P. abies, 26.IX.2011 J. Nordén 9601* (O

F-248016), Svantesson 608* (O). Russia. Khabarovsk Reg.: Sol-

nechnyi Dist., Igdomi, Picea ajanensis, 3.IX.2016 Spirin 10856,

10916 (H). Krasnoyarsk Reg.: Turukhansk Dist., Mirnoye, Pinus

sibirica, 20.VIII.2013 Kotiranta 26387* (H). Leningrad Reg.:

Boksitogorsk Dist., Chagoda, P. abies, 9.V.2018 Spirin 11886*

(H), Kolp’, P. abies, 27.VII.2016 Spirin 10376 (H), Vyalgozero,

P. abies, 13.VII.2014 Spirin 6936 (H); Kirishi Dist., Oblutskoye,

dead Trichaptum abietinum on P. abies, 6.VIII.2019 Spirin

12844 (H); Podporozhie Dist., Vazhinka, P. abies, 21.V.2016

Spirin 10101, 10103, 10106, 10108 (H), 5.VI.2016 Spirin 10182

(H). Nizhny Novgorod Reg.: Arzamas Dist., Pustynsky Nat.

Res., P. sylvestris, 12.VIII.2015 Spirin 9188a* (H); Lukoyanov

Mycological Progress (2021) 20:1275–1296

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1 3

Dist., Panzelka, P. sylvestris, 17.VIII.2015 Spirin 9481* (H),

Razino, U. glabra, 18.VIII.2015 Spirin 9483* (H); Sharanga

Dist., Kilemary Nat. Res., P. abies, 23.VIII.2019 Spirin 12972

(H), 24.VIII.2019 Spirin 13046 (H). Tyumen Reg.: Yamalo-

Nenets Autonomous Dist., W of Labytnangi, decorticated

coniferous log, 24.VIII.1996 Kotiranta 12721 (H). Zabaikalie:

Duldurga Dist., Alkhanai, Pinus sp., 26.VIII.2010 Kotiranta

29616* (H); Kyra Dist., Verkhnii Bukukun, decorticated conif-

erous log, 9.IX.2010 Kotiranta 29923 (H). Slovenia. Gorenjska:

Kranj, Njivica, P. abies, 25.IX.2019 Spirin 13147* (H); Kran-

jska Gora, Vršič, Larix decidua, 5.VI.2019 Spirin 12548* (H),

Zelenci Spring, P. abies, 25.IX.2019 Spirin 13190 (H); Bohinj,

Lipanca, L. decidua, 26.IX.2019 Spirin 13269 (H), P. abies,

6.VI.2019 Spirin 12623* (H), 26.IX.2019 Spirin 13244 (H), P.

mugo, 6.VI.2019 Spirin 12650 (H), Mrežce, P. abies, together

with Membranomyces delectabilis, 26.IX.2019 Spirin 13204

(H); Mojstrana, Triglavska Bistrica, P. abies, 28.IX.2019 Spirin

13468 (H). Sweden. Västra Götaland: Strömstad, Hästeskede, P.

abies, 31.X.2011 J. Nordén 10035 (O). Ukraine. Kharkov Reg.:

Krasnokutsky Dist., Slobozhansky Nat. Park, Quercus robur,

2.VII.2015 Savchenko 72* (CWU 7558). USA. Washington:

Clallam Co., Hurricane Ridge, Abies lasiocarpa, 19.X.2014

Spirin 8740* (H), La Push, Pseudotsuga menziesii, 8.X.2014

Spirin 8262* (H).

Basidiodendron walleynii Spirin, V. Malysheva &

Schoutteten, sp. nov. – Figs.4, 5 and 7

MB 838731

Holotype. Russia. Nizhny Novgorod Reg.: Lukoyanov

Dist., Sanki, 54.841N 44.235E, Quercus robur (rotten stump),

20.VIII.2015 Spirin 9697* (H, isotype – LE).

Etymology: After Ruben Walleyn, a Flemish mycologist and

collector of the ﬁrst modern specimen of this species.

Basidiocarps eﬀused, smooth, ﬁrst waxy, pruinose, whitish

or greyish, then continuous, arid, rather soft, cream-coloured

to pale ochraceous, opaque, 0.02–0.1 mm thick, covering a

few cm, margin gradually thinning-out. Hyphal structure

monomitic, hyphae clamped, easily collapsing, freely spaced;

subicular hyphae thin- or slightly thick-walled, subparallel,

2.5–3 μm diam, subhymenial hyphae thin- or slightly thick-

walled, ascending, 2.5–3 μm diam. Gloeocystidia abundant,

moderately tapering or tubular-clavate, rarely subcapitate,

projecting up to 20 μm, hyaline to very pale yellowish or

brownish, (14.5) 15–38 (39) × (4.6) 5.0–10.7 (11.2) μm (n

= 67/5), often in groups of 3–5. Basidia four-celled, ovoid to

broadly suburniform, (10.0) 10.8–15.7 (17.2) × (7.0) 7.2–11.1

(11.8) μm (n = 70/5), sterigmata gradually tapering, up to 10

× 2.5 μm; involucres indistinct. Basidiospores warted, thin-

walled, compressed-subglobose or globose, (5.0) 5.1–7.0

× (5.2) 5.3–7.2 (7.3) μm (n = 120/4), L = 5.87–6.17, W =

6.07–6.38, Q’ = 0.9–1.0, Q = 0.96–0.98, apiculus prominent,

regular, sometimes slightly asymmetric, up to 2.5 × 2 μm.

Distribution and ecology. Europe (Belgium, France,

Russia); decorticated wood of deciduous trees in temperate

forests.

Remarks. Basidiodendron walleynii produces rather thick,

opaque, soft basidiocarps reminiscent more of Hyphoderma

or Peniophorella spp. than other Basidiodendron species. It

diﬀers from two other European Basidiodendron species with

warted basidiospores, i.e., B. cinerellum and B. trachysporum,

in having a non-gelatinized hymenium, a well-diﬀerentiated

subhymenium consisting of ascending hyphae, and clearly

projecting, variably shaped gloeocystidia. Basidiodendron

walleynii is a temperate species; it occurs on rather tough,

decorticated wood of deciduous trees (Castanea, Erica,

Quercus).

Specimens examined (paratypes). Belgium. Vlaams-Brabant:

Hoeilaart, Zoniënwoud, Kersselaerspleyn, Q. robur, 24.IX.2002

Walleyn 3081* (GENT). France. Aveyron: Boutaran, dead

Inonotus dryadeus, 12.V.1914 Galzin 15320 (herb. Bourdot

13969) (PC 0706667); Forques, Castanea sativa, 20.IV.1912

Galzin 11270 (herb. Bourdot 9068) (PC 0706671), Galzin

11276 (herb. Bourdot 9067) (PC 0706662); Le Rec, C. sativa,

XI.1922 Galzin 27569 (herb. Bourdot 35049) (PC 0706663);

Loubotis, C. sativa, 13.XI.1913 Galzin 14136 (herb. Bourdot

12434) (PC 0706670); Matavalès, C. sativa, 20.IV.1912 Gal-

zin 11329 (herb. Bourdot 9069) (PC 0706664); Mazet Bas, C.

sativa, 16.VII.1912 Galzin 11650 (herb. Bourdot 9070) (PC

0084212), 5.IX.1912 Galzin 11881 (herb. Bourdot 9071) (PC

0084223), 23.X.1915 Galzin 18653 (herb. Bourdot 19447) (PC

0706659), XII.1915 Galzin 19135 (herb. Bourdot 15528) (PC

0706661), 5.XI.1916 Galzin 20597 (herb. Bourdot 19365) (PC

0706668), 24.XII.1916 Galzin 21277 (herb. Bourdot 19356)

(PC 0706669); Travès, Erica arborea, 12.II.1912 Galzin 10712

(herb. Bourdot 9063) (PC 0084224).

Basidiodendron widdringtoniae Spirin, V. Malysheva &

Ryvarden, sp. nov. – Figs.4 and 8

MB 838732

Holotype. Malawi. Southern Prov.: Mulanje, Lichenya Pla-

teau, 15.914S 35.589E, Widdringtonia whytei (rotten decorti-

cated log), 9–10.III.1973 Ryvarden 11307a* (O, isotypes – H,

LE).

Etymology: After Widdringtonia, the host tree of the species.

Basidiocarps eﬀused, smooth, waxy, pruinose-reticulate,

whitish or greyish, 0.01–0.02 mm thick, covering a few cm,

margin gradually thinning-out. Hyphal structure monomitic,

hyphae clamped, partly glued together; subicular hyphae

thin- to slightly thick-walled, subparallel, 2.5–3 μm diam,

subhymenial hyphae thin- to slightly thick-walled, ascending

or interwoven, 2–3 μm diam. Gloeocystidia abundant,

clearly tapering, slightly projecting, hyaline or yellowish

to brownish, (12) 13.5–21 (24) × (3.4) 3.9–5.9 (6.0) μm

(n = 14/1). Basidia two – four-celled, ovoid to broadly

Mycological Progress (2021) 20:1275–1296 1293

1 3

suburniform, (10.2) 11.7–14.2 (14.8) × (8.1) 8.2–10.8 (12.0)

μm (n = 20/1), sterigmata gradually tapering, up to 8 ×

2–2.5 μm; involucres well-developed, often totally covering

basidial cells (except sterigmata); basidia in older hymenium

gluedin groups of 3–4and occasionally embedded in

gelatinous matrix. Basidiospores spiny (spines up to 0.3 μm

long), thin-walled, compressed-subglobose or globose, (5.8)

5.9–6.8 × (6.0) 6.1–7.1 (7.2) μm (n = 30/1), L = 6.24, W =

6.48, Q’ = 0.9–1.0, Q = 0.96, apiculus prominent, regular,

sometimes asymmetric, up to 1.5 × 1.5 μm.

Distribution and ecology. So far known from the type local-

ity; rotten wood of conifers (Widdringtonia whytei).

Remarks. Basidiodendron widdringtoniae is morphologi-

cally most similar to B. mexicanum occurring on coniferous

wood in Mexico. It diﬀers from the latter species mainly due

to thinner basidiocarps and shorter gloeocystidia. However,

our material is too scanty to assure these diﬀerences are

not age-dependent. Therefore, the two species must for the

time being be separated by diﬀerent DNA sequences and

distribution areas.

Discussion

In this study, we present the taxonomy of twelve species of

the B. caesiocinereum complex of which eight are described

as new to science. Our study focused mainly on temperate-

boreal Europe, while sampling from North America and

East Asia was occasional. More data may reveal other

representatives of the B. caesiocinereum group in those

areas, as well as in warm-temperate to Mediterranean regions

of Europe. A few available environmental sequences support

this suggestion. In fact, the species diversity in this complex

could be even higher because B. caesiocinereum and B.

spinosum s. lato were reported from Macaronesia (Roberts

and Spooner 2004), North and Central Africa (Malençon

1954; Roberts 2001), the Caribbean (Roberts 2006, 2008),

Central and South America (Kisimova-Horovitz etal. 1997;

Roberts 2003), and New Zealand (McNabb 1969). This

material awaits proper taxonomic revisions.

Despite rather uniform anatomical traits, members

of the B. caesiocinereum complex are morphologically

distinguishable, although microscopy requires the

use of phase contrast illumination and Cotton Blue as

mounting medium. Only this combination allows the

veriﬁcation of outgrowths on the basidiospore wall and

an identification of their form (warts or spines). As

stated above, the basidiospore ornamentation is a key

morphological character in this group. Combined with

other morphological features (basidiocarp colour and

consistency, size of basidia and gloeocystidia, arrangement

of hymenial cells), as well as ecological and geographic

data, it facilitates the species recognition.

Key for species currently recognized in the Basidioden-

dron caesiocinereum complex

1. Basidiospores s moo th. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 2

1*. Basidiospores ornamented .............................................4

2. Basidiospores 5.1–7.8 × 5.3–8.1 μm, basidia

12–24 × 7–11.5 μm, occasionally with a distinct

stalk-like base. Eurasia, almost exclusively on ang

iosperms...................................................B. caesiocinereum

2*. Basidiospores on average smaller, 5.1–6.8 × 5.2–7 μm,

basidia 10–18 × 7–10.5 μm, devoid of stalk-like base ............3

3. Eurasia, almost exclusively on gymnosperms (Abies, Pic

ea).........................................................................B. glaucum

3*. North America, exclusively on a ngi osp erm s.. ... ...

... ... ... .......................................... ... ... .....................B. robenae

4. Basidiospores w art ed. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 5

4*. Basidiospores spiny ........................................................8

5. Basidia glued in groups. Europe, mostly on gymno-

sperms ..............................................................B. cinerellum

5*. Basidia exposed. On various hosts...................................6

6. Basidiocarps arid, opaque. Subhymenial hyphae well-

visible, ascending. Gloeocystidia tapering or tubular-clavate,

15–38 × 5–11 μm. Temperate Europe, exclusively on angio-

sperms (Erica, Castanea, Quercus) .....................B. walleynii

6*. Basidiocarps waxy, hymenium often gelatinized. Subhy-

menium hyphae usually poorly discernible, glued together.

Gloeocystidia tapering, 13–45 × 3–8 μm. Eurasia and North

America, mostly on gymnosperms ........................................ 7

7. Basidiospores distinctly warted, 4.8–7.4 × 5.0–7.8 μm.

Eurasia and North America........................ B. trachysporum

7*. Basidiospores minutely warted, 5.0–6.2 × 5.2–6.5 μm.

North American North-West ...................... B. inconspicuum

8. Basidia glued in groups. South Africa (Malawi), on gym-

nosperms....................................................B. widdringtoniae

8*. Basidia exposed. On various hosts..................................9

9. Basidiospores with spines up to 0.6 μm long..................10

9*. Basidiospores with spines up to 0.4 μm long ...............11

10. Basidia 9–10 × 6–7.5 μm, basidiospores 4.6–5.2 × 4.8–

5.8 μm. Oceania ................................................. B. spinosum

10*. Basidia 13–18 × 9–12 μm, basidiospores 6.0–7.9 ×

6.2–8.2 μm. Europe .......................................... B. groningae

11. Basidia 12–15.5 × 9.5–12 μm, basidiospores

5.9–7.3 × 6.1–7.4 μm. Mexico (highlands), on gym-

nosperms ..............................................B. mexicanum

11*. Basidia 15–24 × 10–12 μm, basidiospores 6.9–8.2 × 7.1–8.9

μm. Mexico (subtropical zone), on ferns (Cyathea)........................

........................................................................................B. spiculosum

Additional specimens examined

Basidiodendron eyrei. Netherlands. Gelderland: Hoge

Veluwe, decayed wood, 16.XI.2019 Schoutteten 19-411*

(GENT); Groningen: Nieuweschans, Houwingaham,

Mycological Progress (2021) 20:1275–1296

1294

1 3

decayed wood, 24.X.2018 Enzlin 18-101* (GENT);

Oude Pekela, Emergobos, decayed wood, 7.X.2018 Enz-

lin 18-103* (GENT); Ter Apel, Roelage Bos, P. abies,

22.X.2013 Enzlin 13-100* (GENT).

Acknowledgements We are very indebted to the curators of herbaria

FH, PC, NY, TU, TAAM and CWU, who sent us valuable specimens

for loan. Myriam de Haan (Meise Botanical Garden, Ghent, Belgium)

kindly provided us with SEM photographs of B. groningae.

Author contribution All authors contributed to the study conception

and design. Material preparation, data collection and analysis were ini-

tially performed by Viacheslav Spirin, Vera Malysheva, Otto Miettinen,

Ilya Viner and Karl-Henrik Larsson. The authors Nathan Schoutteten,

Jenni Nordén, Heikki Kotiranta, Leif Ryvarden, Annemieke Ver-

beken and Michael Weiß provided further important material and/or

sequences. The ﬁrst draft of the manuscript was written by Viacheslav

Spirin and all authors commented on previous versions of the manu-

script. All authors read and approved the ﬁnal manuscript.

Funding Open access funding provided by University of Helsinki

including Helsinki University Central Hospital. The research was sup-

ported by Norwegian Biodiversity Information Centre (projects “A sur-

vey of Norwegian jelly fungi”, grant number knr. 44-15, the authors

KHL and VS, “Wood-inhabiting corticioid homo- and hetero-basid-

iomycetes in Norway”, grant number knr. 59-12, and “International

workshop on corticioid heterobasidiomycetes in Northern Europe”,

grant number knr. 28-13, the authors JN, KHL, VS), Academy of Fin-

land research grant (number 315927, the authors VS and OM) Komarov

Botanical Institute, Russian Academy of Sciences (project AAAA-

A19-119020890079-6, the author VM), and Flemish Research Council

(FWO) (Fundamental Research Fellowship, grant number 11E0420N,

the author NS).

Data availability DNA sequences used in the present study are avail-

able in GenBank. Alignments were deposited in TreeBase. Fungal

specimens are stored in public herbaria (as indicated under Specimens

examined)

Declarations

Ethics approval Not applicable

Conflict of interests None.

Open Access This article is licensed under a Creative Commons Attri-

bution 4.0 International License, which permits use, sharing, adapta-

tion, distribution and reproduction in any medium or format, as long

as you give appropriate credit to the original author(s) and the source,

provide a link to the Creative Commons licence, and indicate if changes

were made. The images or other third party material in this article are

included in the article’s Creative Commons licence, unless indicated

otherwise in a credit line to the material. If material is not included in

the article’s Creative Commons licence and your intended use is not

permitted by statutory regulation or exceeds the permitted use, you will

need to obtain permission directly from the copyright holder. To view a

copy of this licence, visit http:// creat iveco mmons. org/ licen ses/ by/4. 0/.

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Viacheslav Spirin · Vera Malysheva · Nathan Schoutteten · Ilya Viner · Karl-Henrik Larsson

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Taxonomy and multigene phylogeny of Pseudohydnum (Auriculariales, Basidiomycota)

Article

Full-text available

May 2023

Taxonomy of Pseudohydnum gelatinosum and its sister taxa is revised via morphological data and a four-gene dataset (ITS, ncLSU rDNA, TEF1, RPB1). Identity of P. gelatinosum and Tremellodon pusillus is re-established based on newly collected and sequenced material from their type localities. Pseudohydnum alienum from Europe; P. umbrosum from temperate East Asia; P. cystidiatum, P. meridianum, and P. placibile from Vietnam; and P. omnipavum from North America are described as new to science; P. translucens and P. brunneiceps from East Asia are redescribed. Most Pseudohydnum collections from North America belong to P. gelatinosum ssp. pusillum. A signifcant divergence of TEF1 sequences in P. gelatinosum is discussed

Basidiodendron yunnanense (Auriculariales), a New Species from Southern China Based on Morphological and Molecular Evidence

Article

Jul 2022

Studies in Basidiodendron eyrei and similar-looking taxa (Auriculariales, Basidiomycota)

Article

Full-text available

Nov 2020

To date, Basidiodendron luteogriseum, the generic type of Basidiodendron (Auriculariales, Basidiomycota) has been treated as a synonym of B. eyrei. Our data show they are not conspecific. The identity of other members of the B.eyrei complex, i.e. B.deminutum and B.grandinioides, is clarified based on morphological and DNA data, and 10 new species are described from Eurasia, as well as from North and South America.

RAxML-NG: A fast, scalable, and user-friendly tool for maximum likelihood phylogenetic inference

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Full-text available

May 2019
BIOINFORMATICS

Motivation: Phylogenies are important for fundamental biological research, but also have numerous applications in biotechnology, agriculture, and medicine. Finding the optimal tree under the popular maximum likelihood (ML) criterion is known to be NP-hard. Thus, highly optimized and scalable codes are needed to analyze constantly growing empirical datasets. Results: We present RAxML-NG, a from scratch re-implementation of the established greedy tree search algorithm of RAxML/ExaML. RAxML-NG offers improved accuracy, flexibility, speed, scalability, and usability compared to RAxML/ExaML. On taxon-rich datasets, RAxML-NG typically finds higher-scoring trees than IQTree, an increasingly popular recent tool for ML-based phylogenetic inference (although IQ-Tree shows better stability). Finally, RAxML-NG introduces several new features, such as the detection of terraces in tree space and a the recently introduced transfer bootstrap support metric. Availability: The code is available under GNU GPL at https://github.com/amkozlov/raxml-ng. RAxML-NG web service (maintained by Vital-IT) is available at https://raxml-ng.vital-it.ch/. Supplementary information: Supplementary data are available at Bioinformatics online.

MEGA X: Molecular Evolutionary Genetics Analysis across Computing Platforms

Article

Full-text available

May 2018
MOL BIOL EVOL

The molecular evolutionary genetics analysis (Mega) software implements many analytical methods and tools for phylogenomics and phylomedicine. Here, we report a transformation of Mega to enable cross-platform use on Microsoft Windows and Linux operating systems. Mega X does not require virtualization or emulation software and provides a uniform user experience across platforms. Mega X has additionally been upgraded to use multiple computing cores for many molecular evolutionary analyses. Mega X is available in two interfaces (graphical and command line) and can be downloaded from www.megasoftware.net free of charge.

Fungi That Decay Ponderosa Pine

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Jun 1975

Niedere basidiomyceten aus südbayern III

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Jan 1963

Franz Oberwinkler

Beiträge zur Kenntnis der Corticieen (II Mitteilung)

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Jan 1908

Hymenomycetes de France. I Heterobasidiés

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Studies of Some Tremellaceae. III. The Genus Bourdotia

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Jul 1959

Kenneth Wells

Caribbean heterobasidiomycetes: 3. British Virgin Islands

Article

Jul 2008

Peter Roberts

Seventeen species of heterobasidioid fungi belonging to the orders Auriculariales, Ceratobasidiales, Dacrymycetales, Exidiales, Tremellales, and Tulasnellales are described or reported from the British Virgin Islands. All are newly recorded from the territory. Endoperplexa tortola and Heterochaete inconspicua are described as new species. Heterochaete tenuicula and Serendipita vermifera are newly recorded from the Americas. Ceratobasidium calosporum is newly recorded from the Caribbean area.

Basidiomicetos resupinados de Costa Rica. Exidiaceae. (Tremellales)

Article

Dec 1997

Ten species of Basidiodendron: burtii, caesio-cinerea, cinerea, eyrei, fulvum, pini, rimosa, rimulenta, spinosa and obscura (Martin) Gómez, Kisimova & Oberw. comb. nov., are discussed and reported from Costa Rica. Only one, B. eyrei, was previously known from the country. Exidiopsis is now represented by two species: laccata and macroacantha, the latter is a new geographical extension. The genus Heterochaete was previously represented by one species and three are added. Heterochaete cystidiophora (Lowy) Oberw., Kisimova-Horovitz & L.D. Gómez comb. nov., was described and known only from Brasil, H. hirneoloides, H. maculata and H. shearii are now added to the mycota of Costa Rica.

Studies in the Basidiodendron caesiocinereum complex (Auriculariales, Basidiomycota)

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