ORIGINAL RESEARCH article

Front. Microbiol., 08 December 2022

Sec. Evolutionary and Genomic Microbiology

Volume 13 - 2022 | https://doi.org/10.3389/fmicb.2022.1046777

A new contribution to Megasporoporia sensu lato: Six new species and three new combinations

  • 1. Institute of Microbiology, School of Ecology and Nature Conservation, Beijing Forestry University, Beijing, China

  • 2. School of Agronomy and Life Sciences, Zhaotong University, Zhaotong, China

  • 3. Biology Centre, Czech Academy of Sciences, Institute of Plant Molecular Biology, Ceské Budějovice, Czechia

  • 4. Manaaki Whenua - Landcare Research, Auckland, New Zealand

  • 5. Key Laboratory of Forest and Grassland Fire Risk Prevention, Ministry of Emergency Management, China Fire and Rescue Institute, Beijing, China

Abstract

Megasporoporia sensu lato has recently been intensively studied in China and South America, and four independent clades representing four genera have been recognized phylogenetically. In this study, more samples, mostly from subtropical and tropical Asia, Oceania, and East Africa, are analyzed. A phylogeny based on a 4-gene dataset of sequences (ITS + nLSU + mtSSU + tef) has confirmed the presence of four genera in Megasporoporia sensu lato: Jorgewrightia, Mariorajchenbergia, Megasporia, and Megasporoporia sensu stricto. Six new species, Jorgewrightia austroasiana, Jorgewrightia irregularis, Jorgewrightia tenuis, Mariorajchenbergia subleucoplaca, Megasporia olivacea, and Megasporia sinuosa, are described based on morphology and phylogenetic analysis. Three new combinations are proposed, viz. Jorgewrightia kirkii, Mariorajchenbergia epitephra, and Mariorajchenbergia leucoplaca. To date, 36 species of Megasporoporia sensu lato are accepted and an identification key to these species is provided. In addition, the identification of Dichomitus amazonicus, Dichomitus cylindrosporus, and Megasporoporia hexagonoides is discussed.

Introduction

Megasporoporia Ryvarden and J. E. Wright was established by Ryvarden et al. (). The genus is readily distinguished from other polypore genera by resupinate basidiocarps with large pores, a dimitic hyphal structure, usually the presence of hyphal pegs and dendrohyphidia, and hyaline, thin-walled, and big basidiospores. The species of the genus was found in tropical or subtropical Africa, America, and Asia (Ryvarden et al., ; Lira et al., ; Wang et al., ; Wu et al., ). Li and Cui () performed the first phylogenetic analysis of the genus based on ITS + nLSU sequences, demonstrating that Megasporoporia was a polyphyletic genus with three independent clades nested in Megasporoporia sensu lato. So, they proposed Megasporia B. K. Cui et al., Megasporoporia sensu stricto, and Megasporoporiella B. K. Cui et al. to represent these clades, although these three genera have similar morphology. Subsequently, Yuan et al. () described three new species of Megasporia from China. Recently, Wang et al. () made a comprehensive phylogenetic analysis based on a 4-gene dataset (ITS + nLSU + mtSSU + tef) from 21 species of Megasporoporia sensu lato, and they found a new clade, described four new species, and proposed two combinations. Lira et al. () revised the definition of Megasporoporia sensu lato and proposed Jorgewrightia Gibertoni and C. R. S. Lira and Mariorajchenbergia Gibertoni and C. R. S. Lira. They also confirmed that the four clades nested in Megasporoporia sensu lato were Jorgewrightia, Mariorajchenbergia, Megasporia, and Megasporoporia sensu stricto. In addition, two new species were described and 20 combinations were proposed (Lira et al., ). Several new species have been confirmed recently in Megasporoporia sensu lato, especially from subtropical and tropical areas (Lira et al., ; Wang et al., ).

This study continues to research on the diversity and phylogeny of Megasporoporia sensu lato based on samples from subtropical and tropical Asia, Oceania, and East Africa. Six new species are described and three new combinations are proposed.

Materials and methods

Morphological studies

The voucher specimens are deposited at the herbaria of the Institute of Microbiology, Beijing Forestry University (BJFC); Universidade Federal de Pernambuco (URM); University of Oslo; the National Museum Prague of Czech Republic (PRM); and the private herbarium of Josef Vlasák (JV). Macro-morphological descriptions were based on field notes and herbarium specimens. Special color terms follow Anonymous () and Petersen (). Microscopic analyses follow Wu et al. (). The following abbreviations were used: CB = Cotton Blue, CB+ = cyanophilous in Cotton Blue, CB– = acyanophilous in Cotton Blue, IKI = Melzer's reagent, IKI– = neither amyloid nor dextrinoid, KOH = 2% potassium hydroxide, L = arithmetic average of all spore lengths, W = arithmetic average of all spore widths, Q = L/W ratios, and n = (a/b), where the number of spores (a) is measured from the given number of specimens (b).

DNA extraction, amplification, and sequencing

The CTAB rapid plant genome extraction kit (Aidlab Biotechnologies Co., Ltd, Beijing) procedures were used to extract total genomic DNA from the fruiting bodies and for the polymerase chain reaction (PCR) according to the manufacturer's instructions with some modifications (Chen et al., ; Shen et al., ). The PCR primers for all genes are ITS5 (GGA AGT AAA AGT CGT AAC AAG G), ITS4 (TCC TCC GCT TAT TGA TAT GC), LR0R (ACC CGC TGA ACT TAA GC), LR7 (TAC TAC CAC CAA GAT CT), MS1 (CAG CAG TCA AGA ATA TTA GTC AAT G), MS2 (GCG GAT TAT CGA ATT AAA TAA C), 983F (GCY CCY GGH CAY CGT GAY TTY AT), and 1567R (ACH GTR CCR ATA CCA CCR ATC TT), according to White et al. (), Vilgalys and Hester (), and Rehner and Buckley (). The final PCR volume was 30 μl, which contained 1 μl of each primer, 1 μl extracted DNA, 12 μl ddH2O, and 15 μl 2 × EasyTaq PCR Supermix (TransGen Biotech Co., Ltd., Beijing, China). The PCR procedures for four genes followed Wang et al. ().

Nuclear ribosomal RNA genes of the known 36 species of Megasporoporia sensu lato were used to determine the phylogenetic position of the new species. Gene sequencing was performed at the Beijing Genomics Institute, and the newly-generated sequences were deposited in GenBank. Sequences generated for this study were aligned with additional sequences downloaded from GenBank. All newly generated sequences were deposited at GenBank (http://www.ncbi.nlm.nih.gov/) and are listed in Table 1. Clustal X (Thompson et al., ) and BioEdit (Hall, ) were used to align and collate these sequences. The data matrices were edited in Mesquite v3.04 software (Maddison and Maddison, ). The combined matrix was reconstructed for phylogenetic analysis as a 4-gene dataset (ITS + nLSU + mtSSU + tef). Sequences of Trametes hirsuta (Wulfen) Lloyd and T. ochracea (Pers.) Gilb. and Ryvarden were used as outgroups to root trees (Wang et al., ). The phylogenetic analysis used in this study followed the approach of Zhu et al. () and Sun et al. (). Maximum parsimony (MP), maximum likelihood (ML), and Bayesian inference (BI) were employed to perform phylogenetic analysis.

Table 1

SpeciesSample no.Geographic originGenBank accessionsReferences
ITSnLSUmt-SSUtef
Crassisporus imbricatusDai 10788ChinaKC867350KC867425KX838374Cui et al.,
C. imbricatusCui 6556ChinaKC867351KC867426Cui et al.,
C. leucoporusCui 16801AustraliaMK116488MK116497MK116507MK122986Cui et al.,
C. macroporusCui 14465ChinaMK116485MK116494MK116504MK122983Cui et al.,
C. macroporusCui 14468ChinaMK116486MK116495MK116505MK122984Cui et al.,
C. microsporusCui 16221ChinaMK116487MK116496MK116506MK122985Cui et al.,
Daedaleopsis confragosaCui 6892ChinaKU892428KU892448KX838381KX838418Cui et al.,
D. confragosaCui 9756ChinaKU892438KU892451Cui et al.,
D. hainanensisDai 9268ChinaKU892434KU892458KX838414Li et al.,
D. hainanensisCui 5178ChinaKU892435KU892462KX838413KX838441Li et al.,
D. purpureaDai 8060JapanKU892442KU892475KX838409KX838438Li et al.,
D. purpureaDai 13583aChinaKX832054KX832063KX838412KX838440Cui et al.,
Datronia mollisDai 11456ChinaJX559253JX559292KX838388KX838424Li et al.,
D. mollisDai 11253ChinaJX559258JX559289KX838387Li et al.,
Datroniella subtropicaDai 12883ChinaKC415184KC415191KX838390KX838427Li et al.,
D. subtropicaDai 12885ChinaKC415185KC415192KX838391KX838428Li et al.,
Dichomitus squalensCui 9639ChinaJQ780407JQ780426KX838404KX838436Li and Cui,
D. squalensCui 9725ChinaJQ780408JQ780427KX838403KX838435Li and Cui,
D. squalensCui 15870ChinaON088330ON089003Present study
D. squalensCui 18424ChinaON088331ON089004Present study
D. squalensCui 18438ChinaON088332ON089005Present study
D. squalensDai 15352ChinaON088333ON089006Present study
Echinochaete russicepsDai 13868ChinaKX832051KX832060KX838406KX838437Cui et al.,
E. russicepsDai 13866ChinaKX832050KX832059KX838405Cui et al.,
Favolus acervatusCui 11053ChinaKU189774KU189805KU189956KU189920Zhou and Cui,
F. acervatusDai 10749bChinaKX548953KX548979KX549018KX549043Zhou and Cui,
F. niveusCui 11129ChinaKX548955KX548981KX549019KX549045Zhou and Cui,
F. niveusDai 13276ChinaKX548956KX548982KX549020KX549046Zhou and Cui,
F. pseudoemericiCui 11079ChinaKX548958KX548984KX549022KX549048Zhou and Cui,
F. pseudoemericiCui 13757ChinaKX548959KX548985KX549023KX549049Zhou and Cui,
Hexagonia glabraDai 12993ChinaKX900637KX900683KX900733KX900823Cui et al.,
H. glabraCui 11367ChinaKX900638KX900684KX900734KX900824Cui et al.,
Hornodermoporus latissimusCui 6625ChinaHQ876604JF706340KF051040KF181134Zhao and Cui,
H. latissimusDai 12054ChinaKX900639KX900686KF218297KF286303Cui et al.,
Jorgewrightia austroasianaDai 17884 (holotype)SingaporeMW422260ON089007ON088341Present study
J. austroasianaDai 18627MalaysiaMW422261ON089008Present study
J. bambusaeDai 22106 (holotype)ChinaMW694884MW694912MZ618631Wang et al.,
J. bambusaeDai 20064ChinaMW694885MW694928MW694913MZ618632Wang et al.,
J. cystidiolophoraCui 2642ChinaJQ780390JQ780432Li and Cui,
J. cystidiolophoraCui 2688 (paratype)ChinaJQ780389JQ780431Li and Cui,
J. ellipsoideaDai 19743ChinaMW694879MW694923MW694899MZ669220Wang et al.,
J. ellipsoideaCui 5222 (holotype)ChinaJQ314367JQ314390Li and Cui,
J. fusiformisDai 18596 (holotype)MalaysiaMW694892MW694935MW694920MZ618637Wang et al.,
J. fusiformisDai 18578MalaysiaMW694893MW694936MW694921MZ618638Wang et al.,
J. guangdongensisCui 9130 (holotype)ChinaJQ314373JQ780428Li and Cui,
J. guangdongensisCui 13986ChinaMG847208MG847217MG847229MG867699Cui et al.,
J. hengduanensisCui 8076 (holotype)ChinaJQ780392JQ780433MG847252KF286337Li and Cui,
J. hengduanensisCui 8176ChinaJQ314370KX900697KX900749MG867700Li and Cui,
J. kirkiiRyvarden 32577ZimbabweON088326ON089001ON158685Present study
J. majorCui 10253ChinaJQ314366JQ780437MK116502Li and Cui,
J. majorYuan 1183ChinaJQ314365Li and Cui,
J. rimosaDai 15357 (holotype)ChinaKY449436KY449447MW694908Yuan et al.,
J. rimosaDai 21997ChinaMW422262MW694909Wang et al.,
J. irregularisDai 16449ChinaON088318ON088994Present study
J. irregularisCui 13853 (holotype)ChinaMW694880MW694924MW694900MZ618625Wang et al.,
J. tenuisDai 20510 (holotype)ChinaON088323ON088998ON088338Present study
J. tenuisDai 20517ChinaON088324ON088999ON088339ON158684Present study
J. tropicaCui 13740ChinaKY449438KY449449MW694910MZ618629Yuan et al.,
J. tropicaCui 13660 (holotype)ChinaKY449437KY449448MW694911MZ618630Yuan et al.,
J. violaceaCui 13845ChinaMG847211MG847220MG847232MG867703Cui et al.,
J. violaceaCui 13838ChinaMG847210MG847219MG847231MG867702Cui et al.,
J. yunnanensisCui 12614AChinaKY449442KY449453MW694922MZ618628Yuan et al.,
J. yunnanensisDai 13870 (holotype)ChinaKY449443KY449454MW694907Yuan et al.,
M. epitephraCoveny 219AustraliaON088325ON089000Present study
M. hubeiensisDai 18102ChinaMW694890MW694933MW694918MZ618636Wang et al.,
M. hubeiensisDai 18103ChinaMW694891MW694934MW694919Wang et al.,
Mariorajchenbergia leucoplacaDai 18657 (holotype of Megasporoporiella australiae)AustraliaMW694888MW694931MW694916MZ618634Wang et al.,
M. leucoplacaDai 18658AustraliaMW694889MW694932MW694917MZ618635Wang et al.,
M. leucoplacaICMP 16412New ZealandON944162ON944142Present study
M. leucoplacaICMP 16962New ZealandON944161ON944141Present study
M. leucoplacaICMP 17545New ZealandON944160ON944140Present study
M. pseudocavernulosaYuan 1270 (holotype)ChinaJQ314360JQ314394Li and Cui,
M. pseudocavernulosaDai 19379ChinaMW694882MW694904MZ618626Wang et al.,
M. rhododendriDai 4226 (holotype)ChinaJQ314356JQ314392MW694905Li and Cui,
M. rhododendriCui 12432ChinaMW694883MW694927MW694906MZ618627Wang et al.,
M. subcavernulosaCui 9252ChinaJQ780378JQ780416MG847235MG867706Li and Cui,
M. subcavernulosaCui 14247ChinaMG847213MG847222MG847234MG867705Cui et al.,
M. subleucoplacaRyvarden 11049 (holotype)TanzaniaON088327Present study
Megasporia amazoniaURM 87859BrazilMW989394MW965595Wang et al.,
M. amazoniaURM 85601BrazilKX584455KX619579MW161494Lira et al.,
M. anoectoporaURM 86947BrazilKX584456KX619577MW045831Lira et al.,
M. anoectoporaURM 86928BrazilKX584457KX619580MW161495Lira et al.,
M. cavernulosaURM 83867BrazilKX584458KX619582Lira et al.,
M. hexagonoidesCBS 464.63ArgentinaAY333802Lira et al.,
M. mexicanaJV 1806/4-JHondurasMW989396Wang et al.,
M. olivaceaDai 17908 (holotype)ChinaON088328ON089002ON158686Present study
M. olivaceaDai 17909ChinaON088329ON088340ON158687Present study
M. sinuosaDai 22011ChinaON088321ON088996ON088336ON158682Present study
M. sinuosaDai 22210 (holotype)ChinaON088322ON088997ON088337ON158683Present study
M. sp. 1JV 0904/81USAMW989395Wang et al.,
M. sp. 1JV 0904/52-JUSAJF894107ON088995ON088335ON158681Present study
M. sp. 1JV 0904/50-JUSAJF894105Present study
M. variabilicolorURM 88369BrazilKX584449KX619578MW045833Lira et al.,
M. variabilicolorURM 88368BrazilKX584448KX619574MW161496Lira et al.,
Megasporoporia bannaensisDai 12306 (holotype)ChinaJQ314362JQ314379Li and Cui,
M. bannaensisDai 13596ChinaKX900653KX900702KX900754KX900838Cui et al.,
M. inflataDai 17882MalaysiaMW694886MW694929MW694914Wang et al.,
M. inflataDai 17478 (holotype)MalaysiaMW694887MW694930MW694915MZ618633Wang et al.,
M. minorDai 18322VietnamMW694881MW694925MW694901MZ618624Wang et al.,
M. minorDai 12170 (holotype)ChinaJQ314363JQ314380MW694902KF494980Li and Cui,
M. neosetulosaJV 1008/51-JUSAJF894109Li and Cui,
M. neosetulosaJV 1008/102-JUSAJF894110Li and Cui,
M. neosetulosaURM 85679 (holotype)BrazilKX584459OL684780Lira et al.,
M. neosetulosaURM 85113BrazilKX584460MW045832Lira et al.,
M. neosetulosaJV 0904/139-JUSAON088320Present study
M. setulosaLR 9907 (neotype)TanzaniaOL678508OL684781Lira et al.,
Neodatronia gaoligongensisCui 8055ChinaJX559269JX559286MG847236KX900846Li et al.,
N. gaoligongensisCui 8186ChinaJX559268JX559285MG847237Li et al.,
Perenniporia martiaCui 4055ChinaKX900641KX900688KX900737Cui et al.,
P. martiaCui 7992ChinaHQ876603HQ654114KF051041KF181135Zhao and Cui,
Polyporus tuberasterDai 12462ChinaKU507580KU507582KU507584KU507590Zhou et al.,
P. tuberasterDai 11271ChinaKU189769KU189800KU189950KU189914Zhou et al.,
P. variusCui 12249ChinaKU507581KU507583KU507585KU507591Zhou et al.,
P. variusDai 13874ChinaKU189777KU189808KU189958KU189923Zhou et al.,
Trametes hirsutaRLG 5133TUSAJN164941JN164801JN164891Li and Cui,
T. ochraceaHHB 13445spUSAJN164954JN164812JN164904Li and Cui,

Taxa information and GenBank accession numbers of the sequences used in this study.

New taxa and new sequences are in bold.

Maximum Parsimony and bootstrap values (MP-BS) obtained from 1,000 replicates were performed using PAUP* version 4.0b10 (Swofford, ). All characters were equally weighted, and the gaps were treated as missing data. Trees were inferred using the heuristic search option with TBR branch swapping and 1,000 random sequence additions. Max trees were set to 5,000, branches of zero length were collapsed, and all parsimonious trees were saved. Clade robustness was assessed using bootstrap analysis with 1,000 replicates (Felsenstein, ). 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 generated (Farris, ; Farris et al., ).

Maximum likelihood (ML) was conducted with RAxML-HPC v. 8.2.3 (Stamatakis, ), involving 1,000 ML searches under the GTRGAMMA model, and only the maximum likelihood best tree from all searches was kept. In addition, 1,000 rapid bootstrap replicates were run with the GTRCAT model to assess the ML BS values (ML) of the nodes.

MrMODELTEST v. 2.3 (Posada and Crandall, ; Nylander, ) also was used to determine the best-fit evolution model for the combined datasets of ITS + nLSU and ITS + nLSU + mtSSU + tef sequences for estimating BI. BI was performed using MrBayes v. 3.2.6 (Ronquist and Huelsenbeck, ; Ronquist et al., ) with four simultaneous independent chains for two datasets, where 2 million generations were performed until the split deviation frequency value of <0.01 and were sampled every 100th generation. The first 25% of sampled trees were discarded as burn-in, while the remaining ones were used to calculate the Bayesian Posterior Probabilities (BPP) of the clades.

Branches that received bootstrap support for MP, ML, and BPP more than or equal to 50% (MP and ML) and 0.90 (BPP) were considered significantly supported (Figure 1). The phylogenetic tree was visualized with the program FigTree v. 1.4.3 (http://tree.bio.ed.ac.uk/software/figtree/).

Figure 1

Results

Phylogenetic analysis

Analyses were based on a combined dataset of 4-gene (ITS + nLSU + mtSSU + tef) sequences from 114 fungal collections representing 58 species. According to MrMODELTEST v.2.3, the most suitable model was GTR + I + G, lset nst = 6, rates = invgamma, and prset statefreqpr = Dirichlet (1,1,1,1). The alignment length of the dataset of each tree generated by MP analysis is 3,548 characters, of which 2,238 characters are constant, 1,146 characters are parsimony-informative, and other key data are TL = 5,018, CI = 0.392, RI = 0.772, RC = 0.302, and HI = 0.608. BI analysis generated a congruent topology with an average standard deviation of split frequencies = 0.007589 for MP and ML analyses. Thus, the topology from the MP tree is presented along with statistical values from the MP/ML/BPP algorithms (Figure 1).

The phylogeny shows that the samples of Megasporoporia sensu lato form four clades (Figure 1): Jorgewrightia (90% MP, 98% ML, 1.00 BPP), Mariorajchenbergia (86% MP, 100% ML, 1.00 BPP), Megasporia (100% MP, 100% ML, 1.00 BPP), and Megasporoporia sensu stricto (99% MP, 100% ML, 1.00 BPP).

Fifteen lineages are nested in the Jorgewrightia clade. Among them, three new lineages represent three new species: J. austroasiana sp. nov. (100% MP, 100% ML, 1.00 BPP), J. irregularis sp. nov. (87% MP, 82% ML, 0.90 BPP), and J. tenuis sp. nov. (100% MP, 100% ML, 1.00 BPP), and another lineage represents the taxon J. kirkii comb. nov. (100% MP, 100% ML, 1.00 BPP).

Seven lineages are nested in the Mariorajchenbergia clade. Among them, one lineage represents M. subleucoplaca sp. nov. (52% MP, 88% ML, 0.99 BPP), and two lineages represent M. epitephra comb. nov. (54% MP, 81% ML) and M. leucoplaca comb. nov. (100% MP, 100% ML, 1.00 BPP).

Nine lineages are nested in the Megasporia clade, and among them, two new lineages represent M. olivacea sp. nov. (98% MP, 96% ML, 1.00 BPP) and M. sinuosa sp. nov. (99% MP, 96% ML, 1.00 BPP).

Five lineages are nested in the Megasporoporia sensu stricto clade.

Taxonomy

Jorgewrightia austroasiana Y. C. Dai, Yuan, Ya R. Wang and Y. D. Wu, sp. nov. Figures 2, 3

Figure 2

Figure 3

MycoBank: 845309

Type: Singapore, Bukit Timah Nature Reserve, on a fallen angiosperm branch, 20 July 2017, Dai 17884 (holotype, BJFC025416!).

Etymology: austroasiana (Lat.) refers to the species being found in South Asia.

Basidiocarps annual, resupinate, adnate, corky, without odor or taste when fresh, becoming hard corky upon drying, up to 13 cm long, 2 cm wide, and 0.6 mm thick at the center; sterile margin thinning out, white when fresh, cream when dry, up to 1 mm wide. Pore surface white to cream when fresh, cream to buff when dry; pores round to angular, 3–3.5 per mm; dissepiments thick, entire; subiculum cream, corky, up to 0.2 mm thick; tubes cream, paler than subiculum, corky, up to 0.4 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae indextrinoid, CB+; tissues unchanged in KOH (not swollen). Subicular generative hyphae infrequent, hyaline, thin-walled, occasionally branched, 1.5–2 μm diameter; skeletal hyphae dominant, distinctly thick-walled with a narrow to medium lumen, occasionally branched, interwoven, 1.5–2.5 μm diameter. Tramal generative hyphae hyaline, thin-walled, occasionally branched, 1.5–3 μm diameter; skeletal hyphae dominant, thick-walled with a narrow lumen, frequently branched, mostly flexuous, interwoven, sometimes encrusted by crystals, 2–3.5 μm diameter. Dendrohyphidia absent. Hyphal pegs absent. Cystidia absent; cystidioles present, fusoid, thin-walled, smooth, 14–30 × 6.5–10 μm. Basidia more or less barrel-shaped, with four sterigmata and a basal clamp connection, 24–28 × 9–12 μm; basidioles in shape similar to basidia. Small tetrahedric or polyhedric crystals frequent among hymenium and trama. Basidiospores cylindrical, slightly curved, hyaline, thin-walled, smooth, IKI–, CB–, (14.5–) 15.0–19.5 (−20.0) × (3.2–) 3.5–6.0 (−6.5) μm, L = 16.27 μm, W = 4.50 μm, Q =3.54–3.74 (n = 60/2).

Additional materials (paratypes) examined: Malaysia, Selangor, Kota Damansara, Community Forest Reserve, on a fallen angiosperm branch, 17 April 2018, Dai 18627 (BJFC026915!).

Notes: Phylogenetically, Jorgewrightia austroasiana is related to J. rimosa, J, tenuis, J. fusiformis, and J. irregularis (Figure 1). However, J. rimosa differs from J. austroasiana by its dextrinoid skeletal hyphae and the presence of dendrohyphidia (Yuan et al., ). J. fusiformis and J. tenuis are readily distinguished from J. austroasiana by their fusiform basidiospores (Wang et al., ), J. irregularis differs from J. austroasiana by its bigger pores (0.5–1 per mm vs. 3–3.5 per mm) and the presence of dendrohyphidia and hyphal pegs.

Jorgewrightia irregularis Y. C. Dai, Yuan, Ya R. Wang and Y. D. Wu, sp. nov. Figures 4, 5

Figure 4

Figure 5

MycoBank: 845312

Type: China, Hainan Prov., Baisha County, Yinggeling Nature Reserve, on a fallen angiosperm branch, 17 June 2016, Cui 13853 (holotype, BJFC028719!).

Etymology: irregularis (Lat.) refers to irregular pores of the basidiocarps.

Basidiocarps annual, resupinate, adnate, without odor or taste when fresh, becoming hard corky upon drying, up to 6 cm long, 1.5 cm wide, and 1.3 mm thick at the center; sterile margin cream when juvenile, brownish with age, up to 0.6 mm wide. Pore surface white to cream when fresh, buff to honey when dry; pores angular when juvenile, irregular with age, e.g., hexagonoid, sinuous or split, 0.5–1 per mm; dissepiments thick, entire to lacerate; subiculum pale cream, corky, up to 0.4 mm long; tubes buff, corky, up to 0.9 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae indextrinoid, CB+; tissues unchanged in KOH (not swollen). Subicular generative hyphae infrequent, hyaline, thin-walled, moderately branched, 1–1.2 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, moderately branched, strongly flexuous, interwoven, 2.5–3 μm diameter. Tramal generative hyphae infrequent, hyaline, thin-walled, moderately branched, 1.2–1.5 μm diameter; skeletal hyphae dominant, thick-walled with a narrow lumen, moderately branched, strongly flexuous, interwoven, 2.2–2.5 μm diameter. Dendrohyphidia present. Hyphal pegs present. Cystidia absent; cystidioles present, subulate or ventricose, thin-walled, smooth, 25.5–32.5 × 6.5–8 μm. Basidia more or less clavate, usually constricted in middle, with four sterigmata and a basal clamp connection, 42–51 × 8–13 μm; basidioles in shape similar to basidia, but distinctly smaller. Small tetrahedric or polyhedric crystals present among hymenium and trama. Basidiospores cylindrical, slightly curved, hyaline, thin-walled, smooth, IKI–, CB–, (17–) 17.5–21.2 (−21.5) × (4.5–) 5–6.2 (−6.5) μm, L = 19.22 μm, W = 5.86 μm, Q = 3.22–3.34 (n = 60/2).

Additional materials (paratypes) examined: China, Hainan Prov., Ledong County, Jianfengling Nature Reserve, 11 May 2009, Cui 6592 (BJFC004445!); Qiongzhong County, Limushan Forest Park, on a fallen angiosperm branch, 8 June 2016, Dai 16449 (BJFC022566!).

Notes: Phylogenetically, Jorgewrightia irregularis is related to J. fusiformis (Figure 1), but the latter has fusiform basidiospores and lacks hyphal pegs (Wang et al., ).

Jorgewrightia tenuis Y. C. Dai, Yuan Yuan, Ya R. Wang and Y. D. Wu, sp. nov. Figures 6, 7

Figure 6

Figure 7

MycoBank: 845313

Type: China, Yunnan Prov., Mengla County, Tropical Rain Forest Valley, on dead bamboo, 18 August 2019, Dai 20510 (holotype, BJFC032178!).

Etymology: tenuis (Lat.) refers to the extremely thin basidiocarps.

Basidiocarps annual, resupinate, adnate, corky, without odor or taste when fresh, becoming hard corky upon drying, up to 19 cm long, 3 cm wide, and 0.18 mm thick at the center; sterile margin very narrow to almost lacking. Pore surface cream when fresh, buff when dry; pores angular, 3–3.5 per mm; dissepiments thin, entire; subiculum pale cream, corky, extremely thin to almost absent; tubes cream, corky, up to 0.18 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae sometimes simple septate, weakly dextrinoid, CB+; tissues unchanged in KOH (not swollen). Subicular generative hyphae hyaline, thin-walled, unbranched, 1.5–1.8 μm diameter; skeletal hyphae dominant, thick-walled with a medium to wide lumen, moderately branched, flexuous, interwoven, 2–2.5 μm diameter. Tramal generative hyphae frequent, hyaline, thin-walled, moderately branched, 1.2–1.5 μm diameter; skeletal hyphae dominant, thick-walled with a medium to wide lumen, moderately branched, flexuous, interwoven, 1.5–2.5 μm diameter. Dendrohyphidia absent. Hyphal pegs absent. Cystidia absent; cystidioles absent. Basidia not seen. Small tetrahedric or polyhedric crystals frequent among hymenium and trama. Basidiospores fusiform, hyaline, thin-walled, smooth, sometimes with one or two small guttules, IKI–, CB–, (15–) 16.5–17 (−17.2) × (4.2–) 4.8–5.5 (−5.8) μm, L = 16.47 μm, W = 5.02 μm, Q = 3.28–3.42 (n = 60/2).

Additional materials (paratypes) examined: China, Yunnan Prov., Mengla County, Tropical Rain Forest Valley, on dead bamboo, 18 August 2019, Dai 20517 (BJFC032185!).

Notes: For the phylogenetic relationships of Jorgewrightia tenuis and other species, refer to the notes of J. austroasiana. Morphologically, J. tenuis resembles J. bambusae and J. rimosa by the adnate and extremely thin basidiocarps, but J. bambusae has thick-walled and ellipsoid basidiospores, and J. rimosa has dendrohyphidia (Yuan et al., ; Wang et al., ). In addition, J. tenuis is similar to J. fusiformis, both present with fusiform basidiospores, but J. fusiformis has indextrinoid skeletal hyphae and dendrohyphidia (Wang et al., ).

Jorgewrightia kirkii (Masuka and Ryvarden) Y. C. Dai, Yuan Yuan, Ya R. Wang and Y. D. Wu, comb. nov. Figure 8

Figure 8

MycoBank: 845318

Basionym: Dichomitus kirkii Masuka and Ryvarden, Mycological Research 103 (9): 1129 (1999).

Basidiocarps annual, resupinate, corky when dry, around 1 mm thick at the center; sterile margin very narrow to almost lacking. Pore surface clay buff to isabelline when dry; pores round, 1.5–2 per mm; dissepiments thin, entire; subiculum clay buff, corky, up to 0.2 mm thick; tubes concolorous with the pore surface, corky, up to 0.8 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae indextrinoid, CB+; tissues unchanged in KOH (not swollen). Subicular generative hyphae hyaline, thin-walled, occasionally branched, 1.5–1.8 μm diameter; skeletal hyphae dominant, thick-walled with a wide lumen, moderately branched, flexuous, interwoven, 2.5–3 μm diameter. Tramal generative hyphae, hyaline, thin-walled, moderately branched, 1.2–1.5 μm diameter; skeletal hyphae dominant, thick-walled with a wide lumen, frequently branched, flexuous, interwoven, 1.5–2.5 μm diameter. Dendrohyphidia present. Hyphal pegs absent. Cystidia absent; cystidioles present, fusoid to ventricose, thin-walled, smooth, 23–28 × 6.5–15 μm. Basidia barrel-shaped, with four sterigmata and a basal clamp connection, 30–40 × 16–18 μm; basidioles in shape similar to basidia. Small tetrahedric or polyhedric crystals frequent among hymenium and trama. Basidiospores cylindrical, hyaline, thin-walled, smooth, IKI–, CB–, (20.2–) 21–23.5 (−24) × (7–) 7.5–8.8 (−9) μm, L = 21.86 μm, W = 8.1 μm, Q = 2.70 (n = 30/1).

Materials examined: Zimbabwe, Mashonaland, Binga Forest East of Harare, on an angiosperm wood, 27 January 1993, Ryvarden 32577 (O, dupl. BJFC002897!); Ryvarden 33631 (holotype, O).

Notes: Jorgewrightia kirkii was originally described as Dichomitus kirkii Masuka and Ryvarden from Africa (Masuka and Ryvarden, ). It is extremely large basidiospores (21–23.5 × 7.5–8.8 μm) that are unique in Megasporoporia sensu lato. Our phylogeny (Figure 1) shows that the species is nested in Jorgewrightia clade with robust support (100% MP, 100% ML, 1.00 BPP). Hence, the above combination is proposed.

Mariorajchenbergia epitephra (Berk.) Y. C. Dai, Yuan Yuan, Ya R. Wang and Y. D. Wu, comb. nov. Figure 9

Figure 9

MycoBank: 845319

Basionym: Trametes epitephra Berk., J. Linn. Soc., Bot. 13: 165 (1872).

= Dichomitus epitephrus (Berk.) Ryvarden, Mycotaxon 20 (2): 339 (1984).

Basidiocarps biennial, pileate, solitary, attached by a broad lateral base. Pilei ungulate, hard corky when dry, projecting up to 5 mm, 7 mm wide, and 5.5 mm thick at the base. Pore surface cream to buff when dry; pores round to sinuous, 1–2 per mm; dissepiments thick, entire; subiculum pale buff, corky, up to 0.5 mm thick; tubes concolorous with the pore surface, corky, up to 5 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae indextrinoid, CB+; tissues become slightly swollen in KOH. Subicular generative hyphae hyaline, thin-walled, unbranched, 1.8–2 μm diameter; skeletal hyphae dominant, thick-walled with a wide lumen, infrequently branched, flexuous, interwoven, 2–2.8 μm diameter. Tramal generative hyphae hyaline, thin-walled, unbranched, 1.8–2.5 μm diameter; skeletal hyphae dominant, thick-walled with a medium to wide lumen, infrequently branched, flexuous, interwoven, 2.5–3 μm diameter. Dendrohyphidia absent. Hyphal pegs present. Cystidia absent; cystidioles present, fusoid to clavate, thin-walled, smooth, 26.5–50.5 × 6–13.2 μm. Basidia clavate, with four sterigmata and a basal clamp connection, 28.5–35.5 × 7.5–10.2 μm; basidioles in shape similar to basidia, but slightly smaller. Small tetrahedric crystals frequent among hymenium and trama. Basidiospores broadly ellipsoid, hyaline, thin-walled, smooth, IKI–, CB–, 9.5–16.5 × 7–9 μm, L = 13.28 μm, W =7.8 μm, Q = 1.7 (n = 15/1).

Material examined: Australia, New South Wales, Blackett, on Eucalyptus moluccana, 10 July 1983, Coveny 219 (H, JV, dupl. BJFC002895!).

Notes: Mariorajchenbergia epitephra was originally described as Trametes epitephra from South Australia. Our studied sample fits the original description of Trametes epitephra (Berkeley, ; Cunningham, ). Phylogenetically, the species is nested in the Mariorajchenbergia clade. Therefore, the above combination is proposed. The species has pileate basidiocarps that are unique to Megasporoporia sensu lato.

Mariorajchenbergia leucoplaca (Berk.) Y. C. Dai and P. K. Buchanan, comb. nov.

MycoBank: 845320

Basionym: Polyporus leucoplacus Berk., Fl. N. Zealand 2: 180 (1855).

= Dichomitus leucoplacus (Berk.) Ryvarden, Norweg. J. Bot. 24: 222 (1977).

= Megasporoporiella australiae Y. C. Dai, Yuan Yuan and Ya. R. Wang, in Wang, Wu, Vlasák, Yuan and Dai, Mycosphere 12 (1): 1027 (2021).

Megasporoporiella australiae was recently described in Australia (Wang et al., ). However, its vouchers and samples of Polyporus leucoplacus from New Zealand are nested together in a subclade with robust support in the Mariorajchenbergia clade. In addition, the morphology of these two taxa is similar (Wang et al., ), and the former becomes a synonym of the latter, with the above combination proposed.

Materials examined: Australia, Melbourne, Dandenong Ranges Botanic Garden, on a dead tree of Rhododendron, 12 May 2018, Y. C. Dai 18657 (BJFC027125!, holotype of Megasporoporiella australiae). New Zealand, Auckland, Waitakere Ranges, on a fallen wood, 11 April 1989, P. K. Buchanan 89/037 (ICMP 16412); Northland, William Hewett Reserve, on decaying wood, 2007, B. C. Paulus BCP3987 (ICMP 16962); Taupo, Kurua Reserve, Owhango, 3 Oct 2007, on a decaying branch (probably Dacrydium cupressinum), B. C. Paulus AOD348 (ICMP 17545).

Mariorajchenbergia subleucoplaca Y. C. Dai and P. K. Buchanan, sp. nov. Figure 10

Figure 10

MycoBank: 845315

Type: Tanzania, Morogoro, Uluguri Mts., Morning Side Nature Reserve, 24 February 1973, Ryvarden 11049 (holotype, O; isotype, BJFC002898!).

Etymology: subleucoplaca (Lat.) refers to the species that somewhat resemble Mariorajchenbergia leucoplaca.

Basidiocarps annual, resupinate, corky when dry, around 0.4 mm thick at the center; sterile margin distinct, white, up to 0.2 mm wide. Pore surface cream to buff when dry; pores round, 4–5 per mm; dissepiments thick, entire; subiculum pale cream, corky, up to 0.3 mm thick; tubes concolorous with the pore surface, corky, up to 0.1 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae indextrinoid, CB+; tissues unchanged in KOH (not swollen). Subicular generative hyphae infrequent, hyaline, thin-walled, unbranched, 1.2–1.8 μm diameter; skeletal hyphae dominant, thick-walled with narrow to wide lumen, unbranched, flexuous, interwoven, 2.5–3 μm diameter. Tramal generative frequent, hyphae hyaline, thin-walled, unbranched, 1.2–1.5 μm diameter; skeletal hyphae dominant, thick-walled with a medium to wide lumen, unbranched, interwoven, 2.5–3.5 μm diameter. Dendrohyphidia absent. Hyphal pegs absent. Cystidia absent; cystidioles present, subulate or ventricose, thin-walled, smooth, 22.5–26.5 × 5.5–13.5 μm. Basidia more or less pyriform, with four sterigmata and a basal clamp connection, 23.2–26.5 × 9.5–11 μm; basidioles in shape similar to basidia, but distinctly smaller. Small tetrahedric or polyhedric crystals frequent among hymenium and trama. Basidiospores oblong ellipsoid, hyaline, thin-walled, smooth, IKI–, CB–, (10–) 11–12 × (4.5–) 5–6 μm, L = 10.94 μm, W = 5.2 μm, Q = 2.10 (n = 30/1).

Notes: Mariorajchenbergia leucoplaca was originally described as Polyporus leucoplacus from New Zealand [Berkeley, ; = Dichomitus leucoplacus (Berk.) Ryvarden (Ryvarden, )]. Masuka and Ryvarden () identified Tanzanian samples as D. leucoplacus. Our studied specimen (Ryvarden 11049) was also collected in Tanzania, and phylogenetically (Figure 1) is nested in the Mariorajchenbergia clade with robust support (53% MP, 91% ML, 0.98 BPP). Samples labeled as D. leucoplaca from Africa and New Zealand, therefore, nested into two independent lineages. Thus, we describe the African samples as a new species. It differs from M.leucoplaca by its smaller pores (4–5 per mm vs. 2–4 per mm) and shorter basidiospores (11–12 × 5–6 μm vs. 11.8–15 × 4–6 μm, Wang et al., ).

Megasporia sinuosa Y. C. Dai, Yuan Yuan, Ya R. Wang and Y. D. Wu, sp. nov. Figures 11, 12

Figure 11

Figure 12

MycoBank: 845316

Type: China, Hainan Prov., Qiongzhong County, Limushan Forest Park, on a fallen angiosperm branch, 31 March 2021, Dai 22210 (holotype, BJFC036801!).

Etymology: sinuosa (Lat.) refers to the species having sinuous pores.

Basidiocarps annual, resupinate, adnate, corky, without odor or taste when fresh, becoming hard corky upon drying, up to 3 cm long, 2 cm wide, and 0.6 mm thick at the center; sterile margin distinct, pale buff, up to 1.5 mm wide. Pore surface white to cream when fresh, cream to buff when dry; pores angular to sinuous, 1.5–2 per mm; dissepiments thick, entire to lacerate; subiculum pale buff, corky, up to 0.3 mm thick; tubes cream, corky, up to 0.3 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae strongly dextrinoid, CB+, slightly swollen in KOH. Subicular generative hyphae hyaline, thin-walled, occasionally branched, 1.5–2 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, frequently branched, strongly flexuous, interwoven, 1.8–2.5 μm diameter. Tramal generative hyphae frequent, hyaline, thin-walled, moderately branched, 1.5–1.8 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, frequently branched, strongly flexuous, interwoven, 1.5–2.8 μm diameter. Dendrohyphidia present. Hyphal pegs absent. Cystidia absent; cystidioles present, subulate or ventricose, thin-walled, smooth, 34.5–38.5 × 4.5–6.5 μm. Basidia clavate, usually constricted in middle, with four sterigmata and a basal clamp connection, 20–50.2 × 7–9.2 μm; basidioles similar to basidia, sometimes with a few guttules. Small tetrahedric or polyhedric crystals frequent among hymenium and trama. Basidiospores cylindrical to allantoid, hyaline, thin-walled, smooth, sometimes with one to two small guttules, IKI–, CB–, (15–) 15.2–16.8 (−17.2) × (4.5–) 4.8–5 μm, L = 16.3 μm, W = 4.87 μm, Q = 3.4 (n = 30/1).

Additional materials (paratypes) examined: China, Hainan Prov., Lingshui County, Diaoluoshan Forest Park, on a fallen angiosperm branch, 8 November 2020, Dai 22010 (BJFC035906!), Dai 22011 (BJFC035907!).

Notes: Phylogenetically, Megasporia sinuosa is closely related to M. olivacea (Figure 1), but the latter differs from the former by darker pore surface (deep olive vs. cream to buff), presence of hyphal pegs, and wider basidiospores (5.5–6.5 μm vs. 4.8–5 μm).

Megasporia olivacea Y. C. Dai, Yuan Yuan, Ya R. Wang and Y. D. Wu, sp. nov. Figures 13, 14

Figure 13

Figure 14

MycoBank: 845317

Type: China, Hubei Prov., Wufeng County, Chaibuxi Geopark, on the dead tree of Quercus, 14 August 2017, Dai 17908 (holotype, BJFC025437!).

Etymology: olivacea (Lat.), refers to the species with a deeply olivaceous pore surface when dry.

Basidiocarps annual, resupinate, adnate, hard corky, without odor or taste when fresh, becoming hard corky upon drying, up to 14 cm long, 4.5 cm wide, and 4 mm thick at the center; sterile margin distinct, cream, up to 1.5 mm wide. Pore surface white to cream when fresh, deep olive when dry; pores angular, 0.5–1 per mm; dissepiments thin, entire; subiculum grayish brown, hard corky, up to 0.2 mm thick; tubes grayish buff, hard corky, up to 3.8 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae sometimes simple septate, moderately dextrinoid, CB+, strongly swollen in KOH. Subicular generative hyphae hyaline, thin-walled, occasionally branched, 1.8–2.5 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, moderately branched, flexuous, interwoven, 2–3.5 μm diameter. Tramal generative hyphae hyaline, thin-walled, occasionally branched, 2–2.5 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to wide lumen, unbranched, flexuous, interwoven, 2–3 μm diameter. Dendrohyphidia present. Hyphal pegs present. Cystidia absent. Cystidioles present, subulate or ventricose, thin-walled, smooth, 26–31 × 5.5–6.5 μm. Basidia clavate, usually constricted in middle, with four sterigmata and a basal clamp connection, 38–44 × 9–10 μm; basidioles in shape similar to basidia, but distinctly smaller. Small tetrahedral crystals frequent among hymenium and trama. Basidiospores cylindrical, some slightly curved, hyaline, thin-walled, smooth, IKI–, CB–, (14.5–) 15.2–17 (−18.2) × (4.5–) 5.5–6.5 (−7) μm, L = 16.4 μm, W = 5.69 μm, Q = 2.73–2.95 (n = 60/2).

Additional materials (paratypes) examined: China, Hubei Prov., Wufeng County, Chaibuxi Geopark, on a dead tree of Quercus, 14 August 2017, Dai 17909 (BJFC025438!).

Notes: Morphologically, Megasporia olivacea has a deep olive pore surface when dry which is unique to Megasporoporia sensu lato.

Megasporia sp. 1 Figures 15, 16

Figure 15

Figure 16

Basidiocarps annual, resupinate, adnate, corky, without odor or taste when fresh, becoming hard corky upon drying, up to 8 cm long, 3 cm wide, and 0.6 mm thick at the center; sterile margin indistinct, white, very narrow to almost absent with age. Pore surface pale ochraceous when fresh and dry; pores mostly angular, 2–3 per mm; dissepiments thin, lacerate; subiculum cream, corky, up to 0.2 mm thick; tubes concolorous with the pore surface, corky, up to 0.4 mm long. Hyphal system dimitic; generative hyphae with clamp connections; skeletal hyphae strongly dextrinoid, CB+, strongly swollen in KOH. Subicular generative hyphae hyaline, thin-walled, unbranched, 1.8–2 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, moderately branched, flexuous, interwoven, 2–2.5 μm diameter. Tramal generative hyphae hyaline, thin-walled, occasionally branched, 1.8–2 μm diameter; skeletal hyphae dominant, thick-walled with a narrow to medium lumen, moderately branched, strongly flexuous, interwoven, 2–3 μm diameter. Dendrohyphidia present. Hyphal pegs absent. Cystidia absent; cystidioles present, fusiform, thin-walled, smooth, 18–23 × 5–6 μm. Basidia pyriform to barrel-shaped, with four sterigmata and a basal clamp connection, usually with a few small guttules, 34.5–28.5 × 7.8–10.2 μm; basidioles in shape similar to basidia, but smaller. Small polyhedric crystals frequently present among hymenium and trama. Basidiospores cylindrical, hyaline, thin-walled, smooth, IKI–, CB–, (10.5–) 12.5–14.2 (−15) × (4.2–) 4.5–4.8 (−5) μm, L = 12.98 μm, W = 4.58 μm, Q = 2.76–3.09 (n = 30/2).

Materials examined: USA, Florida, Long Pine Key, April 2009, JV 0904/50-J (JV, BJFC038548!), JV 0904/52-J (JV, BJFC038549!).

Notes: Megasporoporia hexagonoides was originally described as Poria hexagonoides Speg. from Argentina (Spegazzini, ), and a detailed description was given by Ryvarden et al. (). Lira et al. () analyzed the nLSU sequence of the Argentine specimen (CBS 464.63) and treated it as M. hexagonoides. Our studied samples from Florida, USA have the same nLSU sequence as CBS 464.63, but their morphological characteristics are very different from that of M. hexagonoides (the latter has pores 0.5–1 per mm, absence of dendrohyphidia, basidiospores 16.6–21.8 × 5.2–6.8 μm, Ryvarden et al., ).

Poria linearis Murrill, described from Panama (Murrill, ), was treated as a synonym of Megasporia cavernulosa (Berk.) C. R. S. Lira and T. B. Giberton (=Megasporoporia cavernulosa), described from Panuré, Brazil (Berkeley, ). The morphology of the taxon from Florida fits Poria linearis well, but so far no DNA data are available from the Panamanian sample, and for the time being, we treat the Florida samples as Megasporia sp. 1.

Key to known species of Megasporoporia sensu lato

1. Pores < 1 per mm………………………………………. 2

1. Pores > 1 per mm………………………………………. 5

2. Dendrohyphidia present…………………………………3

2. Dendrohyphidia absent…………………………………. 4

3. Hyphal pegs absent…………………Jorgewrightia irregularis

3. Hyphal pegs present……………………Megasporia olivacea

4. Basidiospores > 20 μm long………….Megasporia mexicana

4. Basidiospores < 20 μm long…..Mariorajchenbergia epitephra

5. Pores 5–7 per mm………………………………………..6

5. Pores 1–5 per mm………………………………………..7

6. Pore surface violet to greyish violet……Jorgewrightia violacea

6. Pore surface cream to buff………….. Megasporoporia minor

7. Basidiospores ellipsoid……………………………………8

7. Basidiospores cylindrical, allantoid, or fusiform……….…13

8. Pores 4–5 per mm………………………………………..9

8. Pores 1–2 per mm………………………………………11

9. Basidiospores thick-walled…………Jorgewrightia bambusae

9. Basidiospores thin-walled……………….………………10

10. Skeletal hyphae dextrinoid……………….….….…………

…………………….….….…Mariorajchenbergia rhododendri

10. Skeletal hyphae indextrinoid………………………………

……………………………Mariorajchenbergia subleucoplaca

11. Basidiospores > 15 μm long; pore surface pale purplish brown………………………………Megasporia anoectopora

11. Basidiospores < 15 μm long; pore surface cream to yellow.12

12. Pores 1–1.5 per mm; hyphal pegs present……….…………

…..….………………………………Jorgewrightia ellipsoidea

12. Pores 2 per mm; hyphal pegs absent………………….……

………………………………………Megasporia amazonica

13. Basidiospores fusiform…………………………………14

13. Basidiospores cylindrical or allantoid….….….…………15

14. Dendrohyphidia present; skeletal hyphae indextrinoid.….…

…….….….….………………………Jorgewrightia fusiformis

14. Dendrohyphidia absent; skeletal hyphae weakly dextrinoid...

……………………………………….…Jorgewrightia tenuis

15. Hyphal pegs present……………………………………16

15. Hyphal pegs absent………………………….…………21

16. Cystidioles present………………………….….………17

16. Cystidioles absent…………………………….….….…19

17. Basidiospores > 15 μm long….….….…Jorgewrightia major

17. Basidiospores < 15 μm long……………………………18

18. Basidiospores cylindrical………Megasporoporia bannaensis

18. Basidiospores allantoid……………………………………

…………………….…Mariorajchenbergia pseudocavernulosa

19. Dendrohyphidia present…………………………….….…

…….….…………………Mariorajchenbergia subcavernulosa

19. Dendrohyphidia absent……………………….….….…20

20. Basidiospores 3–4 μm wide; American species……….….…

……………….…………………Megasporoporia neosetulosa

20. Basidiospores 4.2–5.7 μm wide; African species.….….….…

….….….……………………………Megasporoporia setulosa

21. Dendrohyphidia present………………….….…………22

21. Dendrohyphidia absent…………….….…….…………28

22. Skeletal hyphae indextrinoid……………………………23

22. Skeletal hyphae weakly to strongly dextrinoid….….….…24

23. Basidiocarps annual; basidiospores > 20 μm long…………

….….….…………………………………Jorgewrightia kirkii

23. Basidiocarps biennial; basidiospores < 20 μm long.….….…

….……………………………Mariorajchenbergia hubeiensis

24. Skeletal hyphae strongly dextrinoid….….………………25

24. Skeletal hyphae weakly dextrinoid….….….….…………27

25. Cystidioles absent…………………Megasporia cavernulosa

25. Cystidioles present…………………………….….….…26

26. Basidiospores > 15 μm long; Asian species….….….………

…….……………………………………Megasporia sinuosa

26. Basidiospores < 15 μm long; North American species.….…

…………………………….….……………Megasporia sp. 1

27. Basidiocarps cracked when dry…….…Jorgewrightia rimosa

27. Basidiocarps uncracked when dry……….….….….………

……………………………………Jorgewrightia yunnanensis

28. Skeletal hyphae indextrinoid……………………………29

28. Skeletal hyphae moderately to strongly dextrinoid………30

29. Basidiospores > 15 μm long……Jorgewrightia austroasiana

29. Basidiospores < 15 μm long………………….….….….…

………………………………Mariorajchenbergia leucoplaca

30. Cystidioles absent…………….….….…………………31

30. Cystidioles present….….………………………………32

31. Basidiospores 10–11.8 μm long; Asian species……….….…

………………………………………Megasporoporia inflata

31. Basidiospores 12–13 μm long; South American species……

……………………………………Megasporia variabilicolor

32. Skeletal hyphae strongly dextrinoid……………….….…33

32. Skeletal hyphae moderately dextrinoid…………………34

33. Pores 2–3 per mm……………………Jorgewrightia tropica

33. Pores 4–5 per mm…….….….Jorgewrightia guangdongensis

34. Basidiospores 16–21 μm long……Megasporia hexagonoides

34. Basidiospores < 15 μm long……………………………35

35. Pore surface cream to buff, pores 2–3 per mm….….………

…………………………………Jorgewrightia hengduanensis

35. Pore surface pale pinkish-brown to salmon, pores 3–5 per

mm ……………………………Jorgewrightia cystidiolophora.

Discussion

Megasporoporia was established based on M. setulosa (the type from Tanzania), but the type has probably been lost (Ryvarden et al., ). Lira et al. () analyzed sequences from an African specimen (LR 9907), providing the most reliable molecular data for the species, conforming to the Megasporoporia sensu stricto clade. An additional three species were included in Megasporoporia: M. cavernulosa (type from Brazil), M. hexagonoides (type from Argentina), and M. mexicana (type from Mexico). Phylogenetically these three are nested in another clade (Megasporia clade, Lira et al., ).

To date, four genera, Jorgewrightia, Mariorajchenbergia, Megasporia, and Megasporoporia sensu stricto, which include 36 species are accepted in Megasporoporia sensu lato.

The type of Megasporia cavernulosa was from Brazil, and the sequences KX584458 and KX619582 are from the Brazilian specimen URM 83867. Lira et al. () considered this specimen to represent M. cavernulosa. This species was also reported from Florida, USA, and the morphology of our studied Florida samples (JV 0904/81-J, JV 0904/50-J, and JV 0904/52-J) is consistent with the description of M. cavernulosa. However, phylogenetically, these samples are distantly related to URM 83867. So, the occurrence of M. cavernulosa in the USA is uncertain.

Dichomitus amazonicus Gomes-Silva et al. was described from Amazonas (Gomes-Silva et al., ) and was later combined as Megasporia amazonica (Gomes-Silva et al.) C. R. S. Lira and Gibertoni (Lira et al., ). The molecular data of the type specimen of M. amazonica (Ryvarden 48295) are not available. Its phylogenetic analysis was based on specimens URM 85601 (Brazil-Pernambuco) and URM 87859 (Brazil-Bahia), but these two specimens did not cluster together (Lira et al., ). We studied a part of URM 87859 and found that it has a dimitic hyphal system, strongly dextrinoid and CB+ skeletal hyphae, and ellipsoid to subcylindrical basidiospores, (10–) 10.2–11.5 (−12.2) × (4.2–) 4.5–5 μm. These characteristics are consistent with the original description of M. amazonica. Therefore, we believe that URM 87859 represents M. amazonica, and URM 85601 is treated as “M. amazonica” in our phylogeny (Figure 1).

Lira et al. () demonstrated that Dichomitus cylindrosporus (Ryvarden 45186) is nested in the Megasporia clade, and they combined it as Megasporia cylindrospora (Ryvarden) C. R. S. Lira and Gibertoni. However, we studied the type (Ryvarden 44248) of D. cylindrosporus and failed to extract the DNA. Morphologically, we found that Ryvarden 44248 has hyphal pegs and pores 2.5–3 per mm, while Ryvarden 45186 lacks hyphal pegs and has pores 1.5–2 per mm. So, Ryvarden 45186 most probably does not represent D. cylindrosporus, and the phylogenetic relationship between D. cylindrosporus and Megasporoporia sensu lato is uncertain.

Megasporoporia, Megasporia, Jorgewrightia, Mariorajchenbergia, and other genera (Dichomitus, Perenniporia, Crassisporus, Daedaleopsis, Datronia, Neodatronia, Polyporus, etc.) are nested together with robust support in our phylogeny based on our selected samples (Figure 1). Megasporia and Jorgewrightia are related to each other with moderate support. These two genera and Megasporoporia and Mariorajchenbergia seem to be strikingly unrelated to each other although the four genera share a very similar morphology. We currently cannot resolve this dilemma, which requires additional genomic data and further analyses.

Statements

Data availability statement

The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found in the article/supplementary material.

Author contributions

Y-RW, YY, and Y-CD: design of the research. Y-RW: performance of the research. Y-RW, Y-CD, YY, and Y-DW: data analysis and interpretation. Y-RW, H-GL, JV, Y-CD, YY, Y-DW, and PB: the collection of materials. Y-RW, Y-CD, YY, Y-DW, and PB: writing and revising the manuscript. All authors contributed to the article and approved the submitted version.

Funding

This study was supported by the National Natural Science Foundation of China (Project Nos. 32000010 and U1802231).

Acknowledgments

We thank Prof. Leif Ryvarden (Norway), Prof. Bao-Kai Cui (China), and Dr. Slava Spirin (Finland) for allowing us to study their specimens.

Conflict of interest

PB was employed by Manaaki Whenua - Landcare Research.

The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

References

Summary

Keywords

taxonomy, phylogeny, morphology, Polyporaceae, polymerase

Citation

Wang Y-R, Dai Y-C, Liu H-G, Vlasák J, Buchanan P, Yuan Y and Wu Y-D (2022) A new contribution to Megasporoporia sensu lato: Six new species and three new combinations. Front. Microbiol. 13:1046777. doi: 10.3389/fmicb.2022.1046777

Received

17 September 2022

Accepted

10 November 2022

Published

08 December 2022

Volume

13 - 2022

Edited by

Ji-Chuan Kang, Guizhou University, China

Reviewed by

Hiran A. Ariyawansa, National Taiwan University, Taiwan; Hai-Sheng Yuan, Institute of Applied Ecology (CAS), China

Updates

Copyright

*Correspondence: Yuan Yuan Ying-Da Wu

This article was submitted to Evolutionary and Genomic Microbiology, a section of the journal Frontiers in Microbiology

Disclaimer

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

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