Ping Du1, Tian-Xu Cao1, Ying-Da Wu2, Meng Zhou3, Zhan-Bo Liu3. 1. College of Life Science and Technology, Yangtze Normal University, Chongqing 408100, China Yangtze Normal University Chongqing China. 2. China Fire and Rescue Institute, Beijing 102202, China China Fire and Rescue Institute Beijing China. 3. School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China Beijing Forestry University Beijing China.
Abstract
Two new wood-rotting fungi in the family Hymenochaetaceae, Fulvifomes dracaenicola sp. nov. and Hymenochaete dracaenicola sp. nov., are described and illustrated from tropical China based on morphological characteristics and molecular data. It is worth to mention that both of them grow on Dracaena cambodiana which is a kind of angiosperm tree distributed in tropical regions. F. dracaenicola is characterised by perennial, pileate, triquetrous basidioma with yellowish brown fresh pores which becoming honey yellow with silk sheening upon drying, a dimitic hyphal system in trama and monomitic in context, and subglobose basidiospores measuring 4.8-5 × 4-4.1 μm. H. dracaenicola is characterised by annual, resupinate basidioma with a clay buff hymenophore, a dimitic hyphal system, absence of tomentum and cortex, presence of subulate setae, absence of cystidia, presence of cystidioles and simple hyphidia, and oblong ellipsoid basidiospores measuring 5.2-5.8 × 2.5-2.8 µm. The phylogenetic analyses based on ITS + nLSU rDNA sequences confirm the placement of two new species respectively in Fulvifomes and Hymenochaete. Phylogenetically closely related species to the two new species are discussed. Ping Du, Tian-Xu Cao, Ying-Da Wu, Meng Zhou, Zhan-Bo Liu.
Two new wood-rotting fungi in the family Hymenochaetaceae, Fulvifomesdracaenicola sp. nov. and Hymenochaete dracaenicola sp. nov., are described and illustrated from tropical China based on morphological characteristics and molecular data. It is worth to mention that both of them grow on Dracaena cambodiana which is a kind of angiosperm tree distributed in tropical regions. F. dracaenicola is characterised by perennial, pileate, triquetrous basidioma with yellowish brown fresh pores which becoming honey yellow with silk sheening upon drying, a dimitic hyphal system in trama and monomitic in context, and subglobose basidiospores measuring 4.8-5 × 4-4.1 μm. H. dracaenicola is characterised by annual, resupinate basidioma with a clay buff hymenophore, a dimitic hyphal system, absence of tomentum and cortex, presence of subulate setae, absence of cystidia, presence of cystidioles and simple hyphidia, and oblong ellipsoid basidiospores measuring 5.2-5.8 × 2.5-2.8 µm. The phylogenetic analyses based on ITS + nLSU rDNA sequences confirm the placement of two new species respectively in Fulvifomes and Hymenochaete. Phylogenetically closely related species to the two new species are discussed. Ping Du, Tian-Xu Cao, Ying-Da Wu, Meng Zhou, Zhan-Bo Liu.
Murrill (, ) was erected in 1914 and typified by (Murrill) Murrill (Murrill 1914). Wagner and Fischer (2002) thought that comprises species with a dimitic hyphal system, absence of setae, and yellowish, thick-walled basidiospores. Hattori et al. (2014) provided a key to worldwide species of and other species possibly belonging to . Zhou (2014) treated D.A. Reid as a taxonomic synonym of and transferred (Massee) D.A. Reid to . However, (Massee) L.W. Zhou has a monomitic hyphal system, but he thought that the hyphal system might be not a stable character at the generic level within . Salvador-Montoya et al. (2018) redefined and thought should encompass species with a monomitic hyphal system in the context, a dimitic hyphal system in the trama. We agree with Zhou and Salvador-Montoya et al., and consider the genus has a monomitic or dimitic hyphal system.Lév. (, ) was erected in 1846 and typified by (Dicks.) Lév. (Léveillé 1846). Léger (1998) wrote a world monograph of and provided a key of the genus. The genus comprises more than 120 species around the world (He and Dai 2012). is characterised by annual to perennial, resupinate, effused-reflexed to pileate basidioma with smooth, tuberculate, lamellate, poroid or hydnoid hymenophores; a monomitic or dimitic hyphal system; presence of setae, and hyaline, thin-walled, narrowly cylindrical to globose basidiospores (Léger 1998; Parmasto 2001; He and Dai 2012).During investigations on the diversity of wood-rotting fungi from China, five unknown specimens were collected from Hainan Province, and their morphology corresponds to the concepts of and . To confirm their affinity, phylogenetic analyses based on the ITS and nLSU rDNA sequences were carried out. Both morphological characteristics and molecular evidence demonstrated these five specimens represent two new species of , which we describe in the present paper.
Materials and methods
Morphological studies
Macro-morphological descriptions were based on field notes and dry herbarium specimens. Microscopic measurements and drawings were made from slide preparations of dried tissues stained with Cotton Blue and Melzer’s reagent following Dai (2010). Pores were measured by subjectively choosing as straight a line of pores as possible and measuring how many fit per mm. The following abbreviations are used: KOH = 5% potassium hydroxide, CB = Cotton Blue, CB– = acyanophilous, IKI = Melzer’s reagent, IKI– = neither amyloid nor dextrinoid, L = mean spore length (arithmetic average of all spores), W = mean spore width (arithmetic average of all spores), Q = variation in the L/W ratios between specimens studied, and n (a/b) = number of spores (a) measured from given number of specimens (b). In presenting spore size variation, 5% of measurements were excluded from each end of the range and this value is given in parentheses. Special color terms follow Anonymous (1969) and Petersen (1996). Herbarium abbreviations follow Thiers (2018). The studied specimens were deposited at the herbarium of the Institute of Microbiology, Beijing Forestry University ().
Molecular studies and phylogenetic analysis
A CTAB rapid plant genome extraction kit (Aidlab Biotechnologies Co., Ltd., Beijing, China) was used to extract total genomic DNA from dried specimens following the manufacturer’s instructions with some modifications (Cui et al. 2019; Shen et al. 2019). ITS regions were amplified with primers ITS4 and ITS5 (White et al. 1990), and the nLSU with primers LR0R and LR7. The polymerase chain reaction (PCR) procedure for ITS was as follows: initial denaturation at 95 °C for 3 min, followed by 35 cycles at 94 °C for 40 s, 58 °C for 45 s, and 72 °C for 1 min, and a final extension of 72 °C for 10 min. The PCR procedure for nLSU was as follows: initial denaturation at 94 °C for 1 min, followed by 35 cycles at 94 °C for 30 s, 48 °C for 1 min, and 72 °C for 1.5 min, and a final extension of 72 °C for 10 min (Chen et al. 2015). The PCR products were purified and sequenced in the Beijing Genomics Institute, China, with the same primers used in the PCR reactions.Phylogenetic trees were constructed using ITS and nLSU rDNA sequences, and phylogenetic analyses were computed with maximum likelihood (ML), maximum parsimony (MP), and Bayesian inference (BI) methods. Sequences of were adopted mainly from ITS + nLSU tree topologies established by Liu et al. (2020). Sequences of were adopted mainly from ITS + nLSU tree topologies established by He et al. (2017) and Rossi et al. (2020). New sequences generated in this study, along with reference sequences retrieved from GenBank (Table 1 and Table 2), were aligned by MAFFT 6 (Katoh and Toh 2008; http://mafft.cbrc.jp/alignment/server/) using the “G-INS-i” strategy and manually adjusted in BioEdit (Hall 1999). The data matrix was edited in Mesquite v3.04 software (Maddison and Maddison 2010). The sequence alignment was deposited at TreeBase (, http://purl.org/phylo/treebase/phylows/study/TB2:S27995; submission ID 27995) and (, http://purl.org/phylo/treebase/phylows/study/TB2:S27696; submission ID 27696). Sequences of (P. Karst.) Bourdot & Galzin and Niemelä obtained from GenBank were used as outgroups of to root trees following Ji et al. (2017) in the ITS + nLSU analysis. Sequences of (Sowerby) Spirin, Miettinen & K.H. Larss. obtained from GenBank were used as outgroups of to root trees following He et al. (2017) in the ITS + nLSU analysis.
Table 1.
A list of species, specimens and GenBank accession numbers of sequences used in the phylogenetic analysis of .
Taxa
Voucher
ITS
LSU
Fomitiporellacaryophylli
CBS 448.76
AY558611
AY059021
Fulvifomescentroamericanus
JV 0611/III
KX960763
KX960764
F.centroamericanus
JV 0611/8P
KX960757
—
F.dracaenicola
Dai 22093
MW559799
MW559804
F.dracaenicola
Dai 22097
MW559800
MW559805
F.fastuosus
LWZ 20140731-13
KR905674
KR905668
F.fastuosus
LWZ 20140718-29
KR905673
—
F.fastuosus
Dai 18292
MH390411
MH390381
F.grenadensis
JV 1212/2J
KX960756
—
F.grenadensis
JV 1607/66
KX960758
—
F.hainanensis
Dai 11573
KC879263
JX866779
F.halophilus
XG 4
JX104705
JX104752
F.halophilus
JV 1502/4
MH390427
MH390392
F.imbricatus
LWZ 20140728-16
KR905677
KR905670
F.imbricatus
LWZ 20140729-25
KR905678
—
F.imbricatus
LWZ 20140729-26
KR905679
KR905671
F.indicus
Yuan 5932
KC879261
JX866777
F.indicus
O 25034
KC879262
KC879259
F.krugiodendri
JV 0904/1
KX960762
KX960765
F.krugiodendri
JV 0312/24.10J
KX960760
KX960766
F.krugiodendri
JV 1008/21
KX960761
KX960767
F.merrillii
—
JX484013
—
F.nilgheriensis
URM 3028
MH390431
MH390384
F.nilgheriensis
PPT152
MH048095
MH048085
F.rimosus
M 2392655
MH628255
MH628017
F.robiniae
CBS 211.36
AY558646
AF411825
F.robiniae
—
EF088656
—
F.siamensis
XG 2
JX104709
JX104756
F.siamensis
Dai 18309
MH390434
MH390389
F. sp.
PM 950703-1
EU035311
—
F.squamosus
CS385
MF479268
MF479265
F.squamosus
CS444
MF479269
MF479264
F.submerrillii
Dai 17911
MH390405
MH390371
F.submerrillii
Dai 17917
MH390406
MH390372
F.thailandicus
LWZ 20140731-1
KR905672
KR905665
F.xylocarpicola
MU 8
JX104676
JX104723
Inocutisrheades
—
AF237731
—
Inonotushispidus
CBS 388.61
AY558602
—
I.lloydii
Dai 10809
MH390428
MH390378
I.lloydii
Dai 9642
MH390429
MH390379
I.lloydii
Dai 11978
MH390430
MH390380
I.porrectus
CBS 296.56
AY558603
AY059051
I.rigidus
Dai 17496
MH390432
MH390398
I.rigidus
Dai 17507
MH390433
MH390399
Phellinotusneoaridus
URM 80362
KM211294
KM211286
P.piptadeniae
URM 80766
KM211293
KM211285
Phellinuslaevigatus
CBS 122.40
MH856059
MH867554
P.populicola
CBS 638.75
MH860960
MH872729
Phylloporiacrataegi
Dai 18133
MH151191
MH165865
P.ribis
CBS 579.50
MH856765
MN240818
New species is shown in bold.
Table 2.
A list of species, specimens and GenBank accession numbers of sequences used in the phylogenetic analysis of .
Taxa
Voucher
ITS
LSU
Hydnoporiatabacina
He 390
JQ279610
JQ279625
Hymenochaeteacerosa
He 338
JQ279543
JQ279657
H.adusta
He 207
JQ279523
KU975497
H.angustispora
Dai 17045
MF370592
MF370598
H.angustispora
Dai 17049
MF370593
MF370599
H.anomala
He 592
JQ279566
JQ279650
H.asetosa
Dai 10756
JQ279559
JQ279642
H.attenuata
He 28
JQ279526
JQ279633
H.bambusicola
He 4116
KY425674
KY425681
H.berteroi
He 1488
KU975459
KU975498
H.biformisetosa
He 1445
KF908247
KU975499
H.boddingii
MEH 66068
MN030343
MN030345
H.boddingii
MEH 69996
MN030341
MN030347
H.boddingii
MEH 66150
MN030344
MN030344
H.borbonica
CBS 731.86
MH862026
MH873716
H.cana
He 1305
KF438169
KF438172
H.cinnamomea
He 755
JQ279548
JQ279658
H.colliculosa
Dai 16427
MF370595
MF370602
H.colliculosa
Dai 16428
MF370596
MF370603
H.colliculosa
Dai 16429
MF370597
MF370604
H.conchata
MEH 70144
MF373838
—
H.contiformis
He 1166
KU975461
KU975501
H.cruenta
He 766
JQ279595
JQ279681
H.cyclolamellata
Cui 7393
JQ279513
JQ279629
H.damicornis
URM 84261
KC348466
—
H.damicornis
URM 84263
KC348467
—
H.denticulata
He 1271
KF438171
KF438174
H.dracaenicola
Dai 22090
MW559797
MW559802
H.dracaenicola
Dai 22096
MW559798
MW559803
H.duportii
AFTOL ID666
DQ404386
AY635770
H.epichlora
He 525
JQ279549
JQ279659
H.floridea
He 536
JQ279597
JQ279683
H.fuliginosa
He 1188
KU975465
KU975506
H.fulva
He 640
JQ279565
JQ279648
H.globispora
He 911
—
KU975508
H.huangshanensis
He 432
JQ279533
JQ279671
H.hydnoides
He 245
JQ279590
JQ279680
H.innexa
He 555
JQ279584
JQ279674
H.legeri
He 960
KU975469
KU975511
H.longispora
He 217
JQ279537
KU975514
H.luteobadia
He 8
JQ279569
KU975515
H.macrochloae
ARAN-Fungi 7079
MF990738
MF990743
H.megaspora
He 302
JQ279553
JQ279660
H.minor
He 933
JQ279555
JQ279654
H.minuscula
He 253
JQ279546
KU975516
H.murina
He 569
JQ716406
JQ716412
H.muroiana
He 405
JQ279542
KU975517
H.nanospora
He 475
JQ279531
JQ279672
H.ochromarginata
He 47
JQ279579
JQ279666
H.odontoides
Dai 11635
JQ279563
JQ279647
H.orientalis
He 4601
KY425677
KY425685
H.parmastoi
He 867
JQ780063
KU975518
H.paucisetigera
Cui 7845
JQ279560
JQ279644
H.quercicola
He 373
KU975474
KU975521
H.rhabarbarina
He 280
JQ279574
KY425688
H.rheicolor
Cui 8317
JQ279529
—
H.rhododendricola
He 389
JQ279577
JQ279653
H.rubiginosa
He 1049
JQ716407
JQ279667
H.rufomarginata
He 1489
KU975477
KU975524
H.separabilis
He 460
JQ279572
JQ279655
H.setipora
Cui 6301
JQ279515
JQ279639
H.sharmae
CAL 1535
KY929017
KY929018
H.sharmae
66088
MK588753
MK588836
H.spathulata
He 685
JQ279591
KU975529
H.sphaericola
He 303
JQ279599
JQ279684
H.sphaerospora
He 715
JQ279594
KU975531
H.subferruginea
Cui 8122
JQ279521
—
H.subferruginea
He 1598
KU975481
—
H.tasmanica
He 449
JQ279582
JQ279663
H.tongbiguanensis
He 1552
KF908248
KU975532
H.tenuis
He 779
JQ279538
JQ279641
H.tropica
He 574
JQ279587
JQ279675
H.ulmicola
He 864
JQ780065
KU975534
H.unicolor
He 468a
JQ279551
JQ279662
H.verruculosa
Dai 17047
—
MF370600
H.verruculosa
Dai 17052
MF370594
MF370601
H.villosa
He 537
JQ279528
JQ279634
H.xerantica
Cui 9209
JQ279519
JQ279635
H.yunnanensis
He 1447
KU975486
KU975538
New species is shown in bold.
A list of species, specimens and GenBank accession numbers of sequences used in the phylogenetic analysis of .New species is shown in bold.A list of species, specimens and GenBank accession numbers of sequences used in the phylogenetic analysis of .New species is shown in bold.Maximum parsimony analysis was applied to the ITS + nLSU dataset sequences. Approaches to phylogenetic analysis followed Song et al. (2016), and the tree construction procedure was computed in PAUP* version 4.0b10 (Swofford 2002). All characters were equally weighted and gaps were treated as missing data. Trees were inferred using the heuristic search option with tree bisection and reconnection (TBR) branch swapping and 1000 random sequence additions maxtrees were set to 5000, branches of zero length were collapsed, and all parsimonious trees were saved. Clade robustness was assessed using a bootstrap (BT) analysis with 1000 replicates (Felsenstein 1985). Descriptive tree statistics tree length (TL), Consistency Index (CI), Retention Index (RI), Rescaled Consistency index (RC), and Homoplasy Index (HI) were calculated for each maximum parsimonious tree (MPT) generated. Sequences were also analyzed using maximum likelihood (ML) with RAxML-HPC through the CIPRES Science Gateway (Miller et al. 2009; http://www.phylo.org). Branch support for ML analysis was determined by 1000 bootstrap replicates.MrModeltest 2.3 (Posada and Crandall 1998; Nylander 2004) was used to determine the best-fit evolution model for the combined dataset for Bayesian Inference (BI). BI was performed using MrBayes v. 3.2.7a (Ronquist and Huelsenbeck 2003) with four simultaneous independent chains for two datasets, performing 3 million generations () and 5 million generations () until the split deviation frequency value < 0.01, and sampled every 1000th generation. The first 25% sampled trees were discarded as burn-in, while the remaining ones were used to calculate Bayesian posterior probabilities (BPP) of the clades.Branches that received bootstrap support for maximum likelihood (BS), maximum parsimony (BP), and Bayesian posterior probabilities (BPP) greater than 70% (BS), 50% (BP) and 0.95 (BPP) were considered as significantly supported, respectively. FigTree v1.4.2 (Rambaut 2012) was used to visualize the resulting tree.
Results
Phylogeny results
The combined ITS + nLSU dataset included sequences from 50 specimens representing 31 species (Table 1). The dataset had an aligned length of 1693 characters, of which 1013 (60%) were constant, 186 (11%) were variable but parsimony-uninformative, and 494 (29%) were parsimony-informative. MP analysis yielded two equally parsimonious trees (TL = 1841, CI = 0.546, RI = 0.712, RC = 0.389, HI = 0.454). The best model-fi for the ITS + nLSU dataset estimated and applied in the Bayesian analysis was GTR+I+G. Bayesian analysis and ML analysis resulted in a similar topology to the MP analysis, with an average standard deviation of split frequencies of 0.004578 (BI).The phylogeny (Fig. 1) inferred from the ITS and nLSU sequences demonstrated that the new species nested in the clade. Moreover, two specimens of form a lineage with strong support (100% BP, 100% BS, 1.00 BPP, Fig. 1).
Figure 1.
Phylogeny of and related species by MP analysis based on combined ITS and nLSU rDNA sequences. Branches are labelled with maximum likelihood bootstrap > 70%, parsimony bootstrap proportions > 50%, and Bayesian posterior probabilities > 0.95, respectively. New species is in bold.
Phylogeny of and related species by MP analysis based on combined ITS and nLSU rDNA sequences. Branches are labelled with maximum likelihood bootstrap > 70%, parsimony bootstrap proportions > 50%, and Bayesian posterior probabilities > 0.95, respectively. New species is in bold.The combined ITS + nLSU dataset included sequences from 79 specimens representing 69 species (Table 2). The dataset had an aligned length of 2249 characters, of which 1486 (66%) were constant, 248 (11%) were variable but parsimony-uninformative, and 515 (23%) were parsimony-informative. MP analysis yielded 48 equally parsimonious trees (TL = 3261, CI = 0.365, RI = 0.619, RC = 0.226, HI = 0.635). The best model for the ITS + nLSU dataset estimated and applied in the Bayesian analysis was GTR+I+G. Bayesian analysis and MP analysis resulted in a similar topology to the ML analysis, with an average standard deviation of split frequencies of 0.009996 (BI).The phylogeny (Fig. 2) inferred from the ITS and nLSU sequences demonstrated that the new species clustered in the clade and two specimens of form a lineage with strong support (100% BS, 100% BP, 1.00 BPP, Fig. 2).
Figure 2.
Phylogeny of and related species by ML analysis based on combined ITS and nLSU rDNA sequences. Branches are labelled with maximum likelihood bootstrap > 70%, parsimony bootstrap proportions > 50%, and Bayesian posterior probabilities > 0.95, respectively. New species is in bold.
Phylogeny of and related species by ML analysis based on combined ITS and nLSU rDNA sequences. Branches are labelled with maximum likelihood bootstrap > 70%, parsimony bootstrap proportions > 50%, and Bayesian posterior probabilities > 0.95, respectively. New species is in bold.
Taxonomy
Z.B. Liu & Y.C. Dai
sp. nov.4648B76D-75FA-5D94-B7BB-6DC1AF828646838682Figs 3
, 4
Figure 3.
A basidiocarp of (Holotype, Dai 22097). Scale bar: 1.0 cm. Photo by: Yu-Cheng Dai.
Figure 4.
Microscopic structures of (Holotype, Dai 22097) a basidiospores b hyphae of context c hyphae of the tubes. Drawings by: Meng Zhou.
Diagnosis.
is characterised by perennial, pileate, triquetrous basidioma with yellowish brown fresh pores which becoming honey yellow with silk sheening upon drying, a dimitic hyphal system in trama and monomitic in context, subglobose basidiospores measuring 4.8–5 × 4–4.1 μm.A basidiocarp of (Holotype, Dai 22097). Scale bar: 1.0 cm. Photo by: Yu-Cheng Dai.Microscopic structures of (Holotype, Dai 22097) a basidiospores b hyphae of context c hyphae of the tubes. Drawings by: Meng Zhou.
Holotype.
China. Hainan Province, Sanya, Daxiaodongtian Park, N18.299, E109.172, on living tree of , 15.XI.2020, Dai 22097 (BJFC 035989).
Etymology.
(Lat.): referring to the species growing on .
Fruiting body.
Basidioma perennial, pileate, without odor or taste and woody hard when fresh, light in weight when dry. Pilei triquetrous, projecting up to 2.5 cm, 2.3 cm wide and 2.6 cm thick at base. Pileal surface yellowish brown to grayish brown when fresh, vinaceous brown when dry, encrusted, glabrous, zonate, uncracked, margin olivaceous brown. Pore surface yellowish brown when fresh, honey yellow with silk sheening when dry; sterile margin indistinct; pores circular, 5–7 per mm; dissepiments thin, entire. Context cinnamon buff to fawn, corky, often darker near the pileus surface, up to 1.4 cm thick, with a distinct crust (black line) near pileus surface at the basal area, partly with additional crust (black line) within context or above tubes. Tubes cinnamon buff to cinnamon, woody hard, up to 1.2 cm thick, tube layers distinctly stratified, individual tube layer up to 0.5 cm long.
Hyphal structure.
Hyphal system dimitic in trama, monomitic in context; generative hyphae simple septate; tissues darkening but otherwise unchanged in KOH.
Context.
Generative hyphae apricot-orange to brownish-orange, thick-walled with a wide lumen, simple septate, unbranched, regularly arranged, 4.5–6 µm in diam.
Trama of the tubes.
Generative hyphae hyaline, thick-walled, simple septate, occasionally branched, 2–2.5 mm in diam; skeletal hyphae apricot-orange to brownish-orange, thick-walled to subsolid, unbranched, loosely interwoven, 3.5–4 mm in diam. Setae or setal hyphae absent; hymenium collapsed in the studied material, basidia and basidioles not seen.
Spores.
Basidiospores subglobose with an apiculus, yellowish brown, thick-walled, smooth, IKI–, CB–, occasionally collapsed when mature, 4.8–5(–5.5) × 4–4.1 μm, L = 5.02 μm, W = 4.04 μm, Q = 1.22–1.25 (n = 90/3).
Additional specimens (paratypes) examined.
China. Hainan Province, Sanya, Daxiaodongtian Park, N18.299, E109.172, on rotten wood of living , 15.XI.2020, Dai 22093 (BJFC 035986), Dai 22095 (BJFC 035987).Z.B. Liu & Y.C. Dai
sp. nov.36A2207E-6F2E-5D13-9D2D-F13DDC27B60B838683Figs 5
, 6
Figure 5.
A basidiocarp of (Holotype, Dai 22090). Scale bar: 1.0 cm. Photo by: Zhan-Bo Liu.
Figure 6.
Microscopic structures of (Holotype, Dai 22090) a basidiospores b basidia and basidioles c cystidioles d hyphidia e setae f Hyphae from hyphal layer. Drawings by: Meng Zhou.
is characterised by annual, resupinate basidioma with a clay buff hymenophore, a dimitic hyphal system, absence of tomentum and cortex, subulate setae present in hyphal layer, absence of cystidia, presence of cystidioles and simple hyphidia, and oblong ellipsoid basidiospores measuring 5.2–5.8 × 2.5–2.8 µm.A basidiocarp of (Holotype, Dai 22090). Scale bar: 1.0 cm. Photo by: Zhan-Bo Liu.Microscopic structures of (Holotype, Dai 22090) a basidiospores b basidia and basidioles c cystidioles d hyphidia e setae f Hyphae from hyphal layer. Drawings by: Meng Zhou.China. Hainan Province, Sanya, Daxiaodongtian Park, N18.299, E109.172, on dead tree of , 15.XI.2020, Dai 22090 (BJFC 035983).(Lat.): referring to the species s growing on .Basidioma annual, resupinate, adnate, not separable from substrate, hard corky, up to 7.5 cm long, 2 cm wide, and less than 0.1 mm thick at center. Hymenophore surface smooth or locally verruculose, clay buff, with some scattered crevices; margin cinnamon buff, up to 0.4 mm.Hyphal system dimitic; generative hyphae infrequent, simple septate; skeletal hyphae dominant; tissues darkening but otherwise unchanged in KOH.
Subiculum.
Tomentum and cortex absent; hyphal layer present. Generative hyphae infrequent, hyaline, thick-walled, simple septate, often branched, 1–2 µm in diam. Skeletal hyphae cinnamon to orange brown, thick-walled to subsolid, rarely branched, interwoven, 1.5–2.5 µm in diam.
Hymenium.
Hyphae similar to those in hyphal layer. Setal layer present, thickening with age, with one to several rows of overlapping setae. Setae numerous, subulate with blunt to acute tips, orange brown to reddish brown, smooth, occasionally with a hyphal sheath, distinctly thick-walled, 30–57 × 6–10 µm, embedded or projecting up to 35 µm beyond the hymenium. Cystidia absent; cystidioles present, fusoid, hyaline, thin-walled, basally swollen, with a sharp or often hyphoid neck, 10–17 × 2.5–4 μm; Simple hyphidia present, scattered, thick-walled, 15–36 × 2–3.5 µm. Basidia subclavate to subcylindrical, with walls thickening toward the base, with four sterigmata and a basal simple septum, 17–23(–25) × 3.5–5 µm; basidioles similar to basidia but smaller.Basidiospores oblong ellipsoid with an apiculus, hyaline, thin-walled, smooth, IKI–, CB–, occasionally bearing a guttule, (5–)5.2–5.8(–6.1) × 2.5–2.8 µm, L = 5.6 µm, W = 2.68 µm, Q = 2.03–2.15 (n = 60/2).
Additional specimen (paratype) examined.
China. China. Hainan Province, Sanya, Daxiaodongtian Park, N18.299, E109.172, on fallen branch of , 15.XI.2020, Dai 22096 (BJFC 035988).
Discussion
and were found in tropical regions of China. It is interesting that both species growing on .Morphologically, (5–7 per mm) shares similar pores with (M.J. Larsen, Lombard & Hodges) T. Wagner & M. Fisch. (5–7 per mm, Larsen et al. 1985), (5–6 per mm, Salvador-Montoya et al. 2018), Murrill (5–7 per mm, Hattori et al. 2014) and L.W. Zhou (6–7 per mm, Zhou 2015). and share perennial, pileate basidioma, but basidioma of is solitary and glabrous, while basidioma of is imbricate and nodulose. In addition, basidioma of is much bigger (30–40 × 10–20 × 5–10 cm, Larsen et al. 1985) than that of And basidiospores of are bigger than that of (4.8–5 × 4–4.1 µm vs. 4.5 × 3.5 µm, Larsen et al. 1985). and share perennial, triquetrous and solitary basidioma, a monomitic hyphal system in context and dimitic in trama, however, can be distinguished from by its bigger basidiospores (5.5–6 × 4–5.5 µm vs. 4.8–5 × 4–4.1 µm). In addition, has a distinct crust (black line) on the pileal surface, but the crust (black line) is absent in (Gilbertson and Ryvarden 1987). resembles by perennial, glabrous basidioma, a dimitic hyphal system in trama, however, basidioma of is ungulate and pileal surface of is azonate, while basidioma of is triquetrous and its pileal surface is zonate. And can be also distinguished from by its wider basidiospores (4–4.1 µm vs. 3–4 µm, Salvador-Montoya et al. 2018). is similar to by sharing perennial, solitary basidioma, but can be distinguished from by a dimitic hyphal system in context, and its bigger basidiospores (5–5.8 × 4.1–4.8 µm vs. 4.8–5 × 4–4.1 µm, Zhou 2015).Two specimens of form a lineage with strong support (100% BP, 100% BS, 1.00 BPP, Fig. 1) in our phylogeny. is closely related to T. Hatt. et al. (98% BP, 99% BS, 1.00 BPP, Fig. 1) and both species share perennial, pileate basidioma, a dimitic hyphal system in trama and monomitic in context, and occurring in tropical Asia. Morphologically they can be easily differentiated by the presence of crust on the pileus surface. has a distinct crust (black line) on the pileus surface and partly with additional crust (black line) within context or above tubes, but the crust (black line) is absent in. (Hattori et al. 2014). Besides, has applanate pilei pores 7–8 per mm, thin- to thick-walled contextual generative hyphae 2–8 μm wide, and basidiospore 4–5 μm wide (Hattori et al. 2014), while has triquetrous pilei, pores 5–7 per mm, thick-walled contextual generative hyphae 4.5–6 μm wide, and basidiospore 4–4.1 μm wide. In addition, grows on in mangrove while grows on in terrestrial ecosystem.Morphologically, to avoid redescribing the existed species, we review the monograph by Léger (1998) and compare with all the species in the monograph. belongs to the section “FULTOCHAETE” and is similar to (Berk. & M.A. Curtis) Cooke. Both species share resupinate and adnate basidioma, absence of tomentum and cortex, similar setae (30–57 × 6–10 µm vs. 30–60 × 5.5–9 µm in , Cooke 1880), but has a dimitic hyphal system, while has a monomitic or subdimitic hyphal system and smaller basidiospores (5.2–5.8 × 2.5–2.8 µm vs. 3.5–5 × 1.8–2.5 µm, Cooke 1880). Besides, has simple hyphidia in hymenium, but hyphidia are absent in (Cooke 1880).Phylogenetically, two specimens of form a lineage with strong support (100% BP, 100% BS, 1.00 BPP, Fig. 2). clusters together with J.C. Léger & Lanq., S.H. He & Y.C. Dai and Peck with strong support (100% BS, 98% BP, 1.00 BPP, Fig. 2). Morphologically, setae in are shorter than in (30–57 µm vs. 60–70 µm in ). In addition, basidiospores of are oblong ellipsoid while they are suballantoid in (5–6 × 2 µm, Léger and Lanquetin 1987). is different from by a monomitic hyphal system and narrowly cylindrical to allantoid basidiospores (5–7 × 1.8–2.2 µm, He et al. 2017). can be distinguished from through its smaller basidiospores (4.5–5.5 × 2–2.5 µm vs. 5.2–5.8 × 2.5–2.8 µm) and a monomitic hyphal system (Peck 1887).