Biodiversity Data Journal : Taxonomic Paper
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Taxonomic Paper
Monilochaetes pteridophytophila (Australiascaceae, Glomerellales), a new fungus from tree fern
expand article infoJingyi Zhang‡,§,|, Rungtiwa Phookamsak¶,#,¤,«, Ausana Mapook§, Yongzhong Lu, Menglan Lv
‡ School of Food and Pharmaceutical Engineering, Guizhou Institute of Technology, Guiyang, China
§ Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, Thailand
| School of Science, Mae Fah Luang University, Chaing Rai, Thailand
¶ East and Central Asia Regional Office, World Agroforestry Centre (ICRAF), Kunming, China
# Centre for Mountain Futures (CMF), Kunming Institute of Botany, Kunming, China
¤ Research Center of Microbial Diversity and Sustainable Utilization, Faculty of Sciences, Chiang Mai University, Chiang Mai, Thailand
« Honghe Center for Mountain Futures, Kunming Institute of Botany, Chinese Academy of Sciences, Honghe, China
Open Access

Abstract

Background

During taxonomic and phylogenetic studies of fungi on pteridophytes in Thailand, Monilochaetes pteridophytophila sp. nov. was collected from the frond stalks of a tree fern (Alsophila costularis, Cyatheaceae). The new species is introduced, based on evidence from morphology and phylogenetic analyses of a concatenated dataset of LSU, ITS, SSU and RPB2 sequences.

New information

Monilochaetes pteridophytophila differs from extant species of Monilochaetes in having darker conidiophores with fewer septae (1–4-septate). Monilochaetes pteridophytophila forms a distinct clade, basal from other species of Monilochaetes in Australiascaceae. A detailed description and illustrations of the new species are provided. We also provided a synopsis of accepted species of Monilochaetes.

Keywords

one new taxon, Hyphomycetes, Pteridophytes, Sordariomycetes, taxonomy

Introduction

Studies on the diversity of fungi on pteridophytes have revealed many new taxa during the last decade (Mehltreter 2010, Braun et al. 2013, Kirschner and Liu 2014, Guatimosim et al. 2016, Kirschner et al. 2019). An estimated 670 species of fern occur in Thailand (Lindsay and Middleton 2009), making it a suitable area for studying the fungi associated with ferns. However, the study of fungi on ferns is in its infancy (Razikin et al. 2014, Kirschner et al. 2019). Cyatheaceae, a family of scaly tree ferns in Cyatheales, is widely distributed in tropical and subtropical areas (Lehnert 2011, Korall and Pryer 2014). Species of Cyatheaceae diverged ca. 150 (146–168) million years ago during the Late Jurassic period (Korall and Pryer 2014). Many taxa in this family are threatened species, including Cyathea brunoniana, C. gigantea and C. henryi (Balkrishna et al. 2020, Coritico and Amoroso 2020).

Monilochaetes Halst. ex Harter was introduced by Harter (1916) to accommodate a pathogenic fungus, M. infuscans Harter, that caused scurf disease of the sweet potato. Monilochaetes infuscans was first reported by Halsted (1890), but the species is considered invalid due to the lack of morphological description and illustrations. Réblová et al. (2011a) established the family Australiascaceae Réblová & W. Gams to accommodate Australiasca Sivan. & Alcorn (as a sexual morph) and Monilochaetes (as an asexual morph). Sivanesan and Alcorn (2002) introduced Australiasca with A. queenslandica Sivan. & Alcorn as the type species, which was linked to Dischloridium camelliae Alcorn & Sivan as an asexual morph. Réblová et al. (2011a) treated Dischloridium B. Sutton as the generic synonym of Monilochaetes, based on phylogenetic analysis of ITS and LSU sequences. Following the “One Fungus One Name” (1F1N) principle, Australiasca was synonymised under Monilochaetes, the latter being older (Réblová et al. 2016, Hyde et al. 2020a). Hyde et al. (2020a) and Wijayawardene et al. (2020) accepted Australiascaceae in Glomerellales with a single genus Monilochaetes. Index Fungorum (2021) lists nine species in Monilochaetes. These are M. basicurvata (Matsush.) Réblová & Seifert, M. camelliae (Alcorn & Sivan.) Réblová, W. Gams & Seifert, M. dimorphospora Réblová & W. Gams, M. guadalcanalensis (Matsush.) I.H. Rong & W. Gams, M. infuscans, M. laeënsis (Matsush.) Réblová, W. Gams & Seifert, M. melastomae Crous, M. nothapodytis S.X. Zhou, J.C. Kang & K.D. Hyde and M. regenerans (Bhat & W.B. Kendr.) Réblová & Seifert. Of those, seven species have molecular data in NCBI GenBank (Sivanesan and Alcorn 2002, Réblová et al. 2011a, Réblová et al. 2011b, Zhou et al. 2017, Crous et al. 2018).

The sexual morph of Monilochaetes is characterised by superficial, dark brown, obpyriform perithecia with or without setae, with periphysate ostioles; hyaline, branching, septate paraphyses; 8-spored, unitunicate, cylindrical-clavate, short-pedicellate asci; and hyaline, ellipsoidal to ovoid, 0–3-septate ascospores (Sivanesan and Alcorn 2002, Réblová et al. 2011a). The asexual morph of Monilochaetes is characterised by solitary, erect, sometimes curved or geniculate, septate, pale brown to dark brown conidiophores; phialidic, terminal, hyaline to pale brown, ampulliform to cylindrical conidiogenous cells with a shallow collarette; and hyaline, aseptate or rarely septate, oval conidia (Harter 1916, Bhat and Kendrick 1993, Réblová et al. 2011a, Réblová et al. 2011b, Zhou et al. 2017, Crous et al. 2018).

In this study, a new species of Monilochaetes, M. pteridophytophila, is described, illustrated and compared with closely-related taxa. Morphological study and multilocus phylogenetic analyses confirm the identity of the new species and confirm its placement in Monilochaetes.

Materials and methods

Sample collection, isolation and conservation

Frond stalks of Alsophila costularis (tree fern) were collected in a disturbed forest near the roadside in Tak Province, Thailand. Specimens were packed into a plastic bag for transportation to the laboratory and the associated metadata were noted (date, locality and host). Fungal colonies on the host surface were observed and examined using a stereomicroscope (Leica EZ4, Leica Microsystems AG, Singapore). Micro-morphological characters were documented with a Nikon DS-Ri2 digital camera fitted to a Nikon ECLIPSE Ni compound microscope (Nikon, Japan). Measurements of morphological structures (conidiophores, conidiogenous cells and conidia) were made with the Tarosoft (R) Image Frame Work. Figures were processed and combined with Adobe Illustrator CS6 (Adobe Systems, USA).

Single spore isolation was carried out to obtain a pure culture, following the method described by Dai et al. (2017). Germinated conidia were aseptically transferred to potato dextrose agar (PDA) plates and incubated at 25°C. Cultures were grown for 2 weeks and culture characteristics, such as size, shape, colour and texture, were recorded. The holotype specimen and ex-type living culture are deposited in the Herbarium of Mae Fah Luang University (MFLU) and Mae Fah Luang University Culture Collection (MFLUCC), Chiang Rai, Thailand, respectively. An isotype specimen is deposited at the Herbarium of Guizhou Academy of Agricultural Sciences (GZAAS), Guiyang, China.

DNA extraction, PCR amplification and sequencing

Fresh fungal mycelium grown on PDA at 25°C for 2 weeks was used to extract DNA. Genomic DNA was extracted by using the Biospin Fungus Genomic DNA Extraction Kit (BioFlux, China), following the manufacturer’s instructions. We amplified the internal transcribed spacer (ITS) region, the small and large subunits of the ribosomal RNA gene (SSU, LSU) and the second largest subunit of RNA polymerase II (RPB2). Primer pairs and PCR thermal cycle conditions are listed in Table 1. The quality of PCR products was checked on 1% agarose gel electrophoresis stained with ethidium bromide. Successful PCR products were sent to Sangon Biotech (Shanghai, China) for purification and sequencing. Forward and reverse sequence reads were assembled using SeqMan v. 7.0.0 (DNASTAR, Madison, WI). Consensus sequences were submitted to NCBI GenBank (Table 2).

Table 1.

Primers and PCR amplification condition.

Locus

Primers (forward/reverse)

PCR amplification condition

Reference(s)

Large subunit ribosomal RNA (LSU)

LR0R/LR5

1. 95°C – 3 min

Vilgalys and Hester (1990), Hopple (1994), Lu et al. (2017)

2. 94°C – 30 sec

3. 51°C – 50 sec

4. 72°C – 1 min

5. Repeat 2–4 for 30 cycles

6. 72°C – 7 min

7. 4°C on hold

Internal transcribed spacer region of ribosomal DNA (ITS)

ITS1/ITS4

1. 95°C – 3 min

White et al. (1990), Lu et al. (2017)

2. 95°C – 30 sec

3. 51°C – 1 min

4. 72°C – 45 sec

5. Repeat 2–4 for 34 cycles

6. 72°C – 10 min

7. 4°C on hold

Small subunit ribosomal RNA (SSU)

NS1/NS4

1. 94°C – 3 min

White et al. (1990)

2. 94°C – 45 sec

3. 56°C – 50 sec

4. 72°C – 1 min

5. Repeat 2–4 for 40 cycles

6. 72°C – 10 min

7. 4°C on hold

RNA polymerase II second largest subunit (RPB2)

fRPB2-5f/fRPB2-7cR

1. 95°C – 5 min

Liu et al. (1999)

2. 95°C – 1 min

3. 55°C – 2 min

4. 72°C – 90 sec

5. Repeat 2 – 4 for 40 cycles

6. 72°C – 10 min

7. 4°C on hold

DNA sequence alignments and phylogenetic analysis

Closely-related taxa were selected for phylogenetic analyses, based on BLASTn searches in NCBI GenBank (https://blast.ncbi.nlm.nih.gov/Blast.cgi), as well as recent publications (Réblová et al. 2011a, Hongsanan et al. 2017, Zhou et al. 2017, Crous et al. 2018, Dissanayake et al. 2020, Table 2). Sequences of each locus were aligned using the online multiple alignment programme MAFFT version 7 (https://mafft.cbrc.jp/alignment/server/, Katoh et al. 2019) and then manually adjusted in BioEdit 7.1.3.0 (Hall 1999). Phylogenetic relationships were inferred, based on a combined LSU–ITS–SSU–RPB2 dataset. Sequences of each locus were combined to form a concatenated super matrix using SequenceMatrix 1.7.8 and analysed with Maximum Likelihood (ML) and Bayesian Inference (BI) criteria.

Table 2.

Taxa used to infer the phylogenetic tree and their GenBank accession numbers.

Notes: "-" as meaning no data available in GenBank. The newly-generated sequences are underlined. The ex-type strains are in bold.

Taxa

Strain/ Voucher No.

GenBank Accession no.

ITS

LSU

SSU

RPB2

Acrostalagmus luteoalbus

strain V205

KJ443271

KJ443141

KJ443096

KJ443184

Acrostalagmus luteoalbus

strain V206

KJ443272

KJ443142

KJ443097

KJ443185

Collariella bostrychodes

CBS 586.83

KX976642

KX976739

-

KX976838

Colletotrichum acutatum

BBA 67875

AJ301926

AJ301926

AJ301926

-

Colletotrichum circinans

CBS 221.81

NR_111457

NG_069094

NG_062845

-

Colletotrichum gloeosporioides

CBS 79672

-

AY705727

-

-

Colletotrichum gloeosporioides

MCA 2498

DQ286198

DQ286199

-

-

Colletotrichum sansevieriae

MFLU 19–2898

MT177931

MT177958

MT177985

MT432208

Colletotrichum truncatum

BBA 70523

AJ301937

AJ301937

AJ301937

-

Corynascus fumimontanus

CBS 137294

MK919291

LK932706

-

MK919347

Cylindrotrichum clavatum

CBS 125296

GU180627

GU180643

GU180622

-

Cylindrotrichum clavatum

DLUCC 0575

MH120193

MH120184

-

MH120179

Cylindrotrichum gorii

DLUCC 0614

MH120195

MH120189

-

MH120183

Cylindrotrichum oligospermum

CBS 570.76

MH861002

MH872775

-

-

Cylindrotrichum oligospermum

CBS 561.77

GU291801

-

-

-

Cylindrotrichum setosum

DAOM 229246

-

GU180652

GU180617

-

Gibellulopsis nigrescens

CBS 120949

NR_149327

NG_067330

-

LR026149

Gibellulopsis nigrescens

DAOM 226890

GU180631

GU180648

GU180613

GU180664

Kylindria chinensis

MFLUCC 16–0965

MH120190

MH120186

-

MH120181

Kylindria peruamazonensis

CBS 838.91

GU180628

GU180638

GU180609

GU180656

Kylindria peruamazonensis

CBS 421.95

GU291800

HM237325

-

-

Lectera nordwiniana

CBS 144921

NR_161150

NG_066300

-

MK047549

Lectera nordwiniana

JW231013

MK047462

MK047512

-

MK047550

Lectera sambuci

CPC 36475

NR 170055

MT223905

-

-

Leptosillia pistaciae

CBS 128196

NR 160064

MH798901

-

MH791334

Malaysiasca phaii

CBS 141321

KX228280

KX228331

-

-

Malaysiasca phaii

MFLUCC 16–0256

MH275069

MH260302

MH260342

-

Monilochaetes camelliae

BRIP 24607

HM237327

HM237324

-

-

Monilochaetes camelliae

BRIP 24334c

HM237326

HM237323

-

-

Monilochaetes dimorphospora

MUCL 40959

NR_137765

HQ609480

NG 062390

-

Monilochaetes guadalcanalensis

CBS 346.76

GU180625

GU180640

-

-

Monilochaetes infuscans

CBS 379.77

-

GU180645

GU180619

GU180658

Monilochaetes infuscans

CBS 870.96

-

GU180644

GU180621

-

Monilochaetes infuscans

CBS 869.96

GU180626

GU180639

GU180620

GU180657

Monilochaetes laeensis

MR 2875

GU180624

GU180642

-

-

Monilochaetes laeensis

DAOM 226788

GU180623

GU180641

GU180610

-

Monilochaetes melastomae

CBS 145059

NR_161124

NG_068601

-

-

Monilochaetes nothapodytis

TRY2 34

MF153475

MF153476

-

-

Monilochaetes pteridophytophila

MFLUCC 21 – 0022

MW826218

MW826219

MW826220

MW829186

Maximum Likelihood (ML) analysis was performed using IQ-TREE (Nguyen et al. 2015, Chernomor et al. 2016) under partitioned models. The optimal nucleotide substitution model for each locus was selected under the corrected Akaike Information Criterion (AICc) using jModelTest2 (Darriba et al. 2012) on XSEDE via the CIPRES Science Gateway 3.3 (https://www.phylo.org/portal2/home.action, Miller et al. 2010). The TIM3+I+G model (-lnL = 3601.7319) was selected for LSU, GTR+I+G (-lnL = 4351.9427) for ITS, TIM1+G (-lnL = 2071.9778) for SSU and TIM2+I+G (-lnL = 7734.2580) for RPB2. A non-parametric bootstrap (BS) analysis was implemented with 1000 replicates (Hoang et al. 2018).

The aligned fasta file was converted to nexus file format for BI analyses using AliView. BI analyses were performed in CIPRES (Miller et al. 2010) with MrBayes on XSEDE 3.2.7a (Ronquist et al. 2012). The best-fit evolutionary model for BI analysis was determined using MrModeltest v.2 (Nylander 2004). For the LSU, ITS and RPB2 datasets, GTR+I+G was selected, whereas GTR+G was selected for SSU. Bayesian posterior probabilities (PP) (Rannala and Yang 1996) were evaluated, based on Markov Chain Monte Carlo (MCMC) sampling. Four simultaneous Markov chains were run for 10,000,000 generations and trees were sampled every 1,000th generation (yielding 10,000 total trees). The first 2,500 trees, which represented the burn-in phase of the analysis, were discarded. The remaining 7,500 trees were used to calculate PP in the majority rule consensus tree.

Phylogenetic trees were visualised using FigTree v. 1.4.0 (Rambaut and Drummond 2008) and edited using Microsoft Office PowerPoint 2010 and Adobe Illustrator CS6 (Adobe Systems, USA). The final alignments and trees were deposited in TreeBASE (http://www.treebase.org/, accession number: 27987).

Taxon treatment

Monilochaetes pteridophytophila J.Y. Zhang, K.D. Hyde & Y.Z. Lu, sp. nov.

Materials    Download as CSV 
Holotype:
  1. scientificName:
    Monilochaetes pteridophytophila
    ; phylum:
    Ascomycota
    ; class:
    Sordariomycetes
    ; order:
    Glomerellales
    ; family:
    Australiascaceae
    ; locationRemarks:
    THAILAND, Tak Province, Umphang District, Mo Kro Subdistrict, 16°12'11"N, 98°52'5"E, 21 August 2019
    ; habitat:
    Terrestrial
    ; fieldNotes:
    on dead frond stalks of Alsophila costularis Baker (Cyatheaceae) in a disturbed forest nearby the roadside
    ; recordedBy:
    Jing Yi Zhang
    ; collectionID:
    MFLU 21–0023
    ; collectionCode:
    Y26
Isotype:
  1. collectionID:
    GZAAS 21-0015

Description

Saprobic on dead frond stalks of Alsophila costularis. Sexual morph: Undetermined. Asexual morph: Hyphomycetous (Fig. 1), colonies on natural substrate superficial, effuse, gregarious, white. Conidiophores (268–)360–565 μm high (x̄ = 465 μm, n = 15), 9–14.5 μm wide (x̄ = 12 μm, n = 15) near the base, macronematous, unbranched, solitary, erect, straight or slightly flexuous, monophialidic, subcylindrical, thick-walled, 1–4-septate, dark brown to black, darker near the base, becoming paler brown towards the apex. Conidiogenous cells 25–54 × 7–11.5 μm (x̄ = 38 × 9.5 μm, n = 20), enteroblastic, monophialidic, terminal, swollen, with a shallow collarette, subcylindrical with apical taper to truncate apex, pale brown, rough. Conidia 20–24 × 10–12 μm (x̄ = 22 × 11.7 μm, n = 30), oblong to obovoid or ellipsoidal, occasionally with a median or submedian constriction, thick-walled, hyaline, aseptate, rough-walled.

Figure 1.  

Monilochaetes pteridophytophila (MFLU 21-0023, holotype). a. The host tree fern (Alsophila costularis) in the field; b. Dead frond stalks of tree fern; c. Colony on dead frond stalk of tree fern; d. Conidiophore; eg. Conidiogenous cells with attached conidia; h. Germinating conidium; in. Conidia; o. Colony on PDA from above and below. Scale bars: c = 200 μm, d = 100 μm, eh = 20 μm, in = 10 μm.

Culture characteristics: Conidia germinating on PDA within 12 hours at 25℃, with hyaline germ tube germinating from the base of conidia. Colonies growing on PDA at 25℃, circular, flat surface, planar, thin, dark brown, reaching 2 cm diam. in 7 days, edge entire, emission at margin, dark brown to pale brown in reverse from the centre to margin of the colony.

Material: ex-type living culture, MFLUCC 21–0022.

Etymology

Referring to the host, which is a pteridophyte.

Notes

Monilochaetes pteridophytophila formed a distinct phylogenetic clade, which clustered with other species of Monilochaetes (Fig. 2). Following BLASTn searches, the closest matches of M. pteridophytophila are M. melastomae (LSU, NG_068601, 98.21% shared identity; ITS, NR_161124, 84.5%), M. laeensis (SSU, GU180610, 99.4%) and M. infuscans (RPB2, GU180658, 80.64%). Monilochaetes pteridophytophila is most similar to M. regenerans in the shape of conidiophores, conidiogenous cells and conidia (Bhat and Kendrick 1993). However, M. pteridophytophila has darker and longer conidiophores [(268–)360–565 μm vs. 300 μm high], shorter conidiogenous cells (25–54 μm vs. 70–100 μm) and smaller conidia (20–24 × 10–12 μm vs. 25–38 × 12–16 μm). Therefore, we introduce M. pteridophytophila as a new species, based on both phylogenetic and morphological evidence.

Figure 2.  

Phylogenetic tree generated from ML analysis, based on a concatenated LSU–ITS–SSU–RPB2 dataset. BS ≥ 70/PP ≥ 0.95 are indicated at the nodes. The newly-generated strain is shown in red and bold. Ex-type strains are indicated by black and bold. Collariella bostrychodes (CBS 586.83), Corynascus fumimontanus (CBS 137294) and Leptosillia pistaciae (CBS 128196) were used as outgroup taxa.

Analysis

Analysis Ⅰ: Phylogenetic reconstruction of a combined LSU, ITS, SSU and RPB2 sequence dataset

The aligned, concatenated sequence matrix comprised sequence data for 39 taxa from seven families of the following loci: LSU (853 bp), ITS (489 bp), SSU (1,014 bp) and RPB2 (1,061 bp). Included sequences represented taxa of Glomerellales and three outgroup taxa, Collariella bostrychodes (CBS 586.83), Corynascus fumimontanus (CBS 137294) and Leptosillia pistaciae (CBS 128196). The sequence matrix comprised 3,417 characters (including gaps), of which 2,317 characters were constant, 185 variable characters were parsimony-uninformative and 915 characters were parsimony-informative. The matrix had 1,188 distinct alignment patterns, with 40.80% undetermined characters or gaps. The ML and BI analyses of the concatenated LSU–ITS–SSU–RPB2 dataset resulted in similar tree topologies (Fig. 2).

The phylogenetic tree shows that all strains of Monilochaetes clustered within Australiascaceae. The new species M. pteridophytophila forms a distinct clade, basal to other species of Monilochaetes with BS = 98% MLBS and PP = 1.00 (Fig. 2).

Discussion

Monilochaetes is a widespread genus, with species occurring as endophytes, pathogens or saprobes on various plants in terrestrial environments (Rashmi et al. 2019, Table 3). All currently-described species of Monilochaetes have hyphomycetous asexual morphs. Only M. camelliae, M. dimorphospora and M. nothapodytis have dimorphic hyphomycetous asexual forms (Réblová et al. 2011a, Réblová et al. 2011b, Zhou et al. 2017). Monilochaetes camelliae and M. laeensis are represented also by sexual morphs (Sivanesan and Alcorn 2002, Réblová et al. 2011a).

Table 3.

Synopsis of asexual morph of accepted species in Monilochaetes with morphological features.

Species

Hosts

Distribution

Macroconidiophores/ Microconidiophores (μm)

Macroconidia/ Microconidia (μm)

Reference(s)

Monilochaetes basicurvata

Palm petiole

Peru

200–300(–600) × 5–7 / -

9–25 × 3.5–6(–7) / -

Matsushima (1995)

M. camelliae

Branch of Camellia sinensis

Australia

200–720 × 9–10(–10.5) / 40–60 × 2–2.5

20.5–24(–26.5) × (10–)11–12 / 4–5.5 × 3–3.5

Sivanesan and Alcorn (2002), Réblová et al. (2011a)

M. dimorphospora

Decayed wood

Cuba

230–450 × 6.5–7 / 40 × 3

21–25(–27) × 6.5–7 /

4.5–6(–6.5) × 2.5–3

Réblová et al. (2011b)

M. guadalcanalensis

Decaying leaf of Musa sp.

Solomon Islands

150–220(–400) × 4–7 / -

18–21 × 6–9 /-

Rong and Gams (2000)

M. infuscans

Ipomoea batatas (sweet potato)

Asia, Australia, Europe, New Zealand, South Africa, Pacific Islands, USA

60–400 / -

15–20 × 4–6 / -

Harter (1916), Lawrence et al. (1981), Rong and Gams (2000)

M. laeensis

Leaf litter, dead stipes and spathes of a tree fern, rotting frond stems of Victoria regia, dead stipes of Dicksonia antarctica and dead palm spathes

Australia, British Isles, Cuba, Ethiopia, India, Malaysia, Papua New Guinea, Sabah and Sri Lanka.

40–160(–280) × 7–8 / -

(15.5–)18–22.5(–23.5) × 7.5–9(–10) / -

Bhat and Sutton (1985), Kirk (1986), Rong and Gams (2000), Réblová et al. (2011a)

M. melastomae

Leaf spots of Melastoma sp.

Malaysia

90 – 250 × 6 –10 /-

(17–)18–19(–20) × (7.5–)8 / -

Crous et al. (2018)

M. nothapodytis

Healthy leaf of Nothapodytes pittosporoides

China

300–640 × 7.5–13 /

18–35 × 4–5.5

16.5–24 × 9.5–15.5 /

3–4.9 × 2.9–4

Zhou et al. (2017)

M. pteridophytophila

Dead frond stalks of Alsophila costularis

Thailand

(268–)360–565 × 9–14.5 / -

20–24 × 10–12 / -

This study

M. regenerans

Dead twigs of Ficus sp.

India

300 × 8–10 / -

25–38 × 12–16 / -

Bhat and Kendrick (1993)

Monilochaetes pteridophytophila is the second species found on a tree fern; M. laeensis occurs on tree ferns in Australia and the UK (Kirk 1986, Réblová et al. 2011a). Monilochaetes pteridophytophila forms a distinct clade with M. laeensis, basal to other Monilochaetes species. However, M. pteridophytophila differs from M. laeensis in having darker and longer conidiophores [(268–)360–565 μm vs. 40–160(–280) μm]. Hyde et al. (2018) and Hyde et al. (2020b) showed high fungal diversity in Thailand and suggested that studies on new hosts and new areas would lead to discovery of further new fungal species. Further studies of fungi on pteridophytes are likely expected to reveal more novel species.

Glomerellales was proposed by Réblová et al. (2011a) to accommodate three families, based on morphology and multilocus phylogenetic data: Australiascaceae, Glomerellaceae and Reticulascaceae. Later, Maharachchikumbura et al. (2016) accepted Plectosphaerellaceae in Glomerellales, based on the analysis of a combined LSU–SSU–TEF1–RPB2 dataset. Malaysiascaceae was added to Glomerellales by Tibpromma et al. (2018), based on a combined ribosomal DNA dataset (SSU, ITS, LSU). Our phylogenetic study confirms Glomerellales as a robust clade (ML = 100, PP = 1.00) comprising five lineages: Australiascaceae (ML = 98, PP = 1.00), Glomerellaceae (ML = 95, PP = 1.00), Malaysiascaceae (ML = 100, PP = 1.00), Plectosphaerellaceae (ML = 100, PP = 1.00) and Reticulascaceae (ML = 99, PP = 1.00). The phylogenetic relationships of families in Glomerellales are in agreement with Tibpromma et al. (2018) and Hyde et al. (2020a).

The tree topologies resulting from the phylogenetic reconstruction of a combined LSU–ITS dataset (analysis Ⅱ, Suppl. material 1) and the concatenated LSU–ITS–SSU–RPB2 dataset (analysis Ⅰ, Fig. 2) were overall similar and not significantly different. A comparison of phylogenetic analysis Ⅰ and Ⅱ with the analysis by Hyde et al. (2020a) showed negligible variation in tree topologies in Glomerellales, even with the inclusion of SSU and RPB2 data. The phylogeny in the current study suggests that LSU and ITS sequences can resolve interspecific relationships within Monilochaetes, as well as interfamilial relationships within Glomerellales.

Acknowledgements

This work was funded by the National Natural Science Foundation of China (NSFC 32060013) and Youth Science and Technology Talent Development Project from Guizhou Provincial Department of Education (QJHKYZ[2021]263). Jing-Yi Zhang would like to thank Shaun Pennycook, De-Ping Wei, and Rong-Ju Xu for their help. Rungtiwa Phookamsak thanks CAS President’s International Fellowship Initiative (PIFI) for Young Staff (grant no. Y9215811Q1), the National Science Foundation of China (NSFC) project code 31850410489 (grant no. Y81I982211) and Chiang Mai University for their partial support of this research.

References

Supplementary material

Suppl. material 1: Phylogenetic analysis of a combined LSU and ITS sequence data 
Authors:  Jingyi Zhang
Data type:  phylogenetic tree
Brief description: 

Analysis Ⅱ: Phylogenetic analysis of a combined LSU and ITS sequence data

The aligned sequence matrix comprises LSU (853 bp) and ITS (489 bp) sequence data for 39 taxa from GenBank. The aligned sequence matrix comprises 1,342 characters after alignment including the gaps, of which 873 characters were constant, 67 variable characters were parsimony-uninformative and 402 characters were parsimony informative. The matrix had 518 distinct alignment patterns, with 10.95% undetermined characters or gaps. The RAxML and BI analyses, based on combined LSU and ITS sequence data, provided similar tree topologies and the result of ML analysis is shown in FIGURE S1.