DNA isolation, amplification and analyses

Genomic DNA was extracted from fungal colonies growing on 2 % malt extract agar (MEA; Oxoid) using the UltraClean™ Microbial DNA Isolation kit (MoBio Laboratories, Inc., Solana Beach, CA, USA) and Wizard® Genomic DNA purification kit (Promega, Madison, USA), according to the manufacturer’s protocols. The primers V9G (De Hoog & Gerrits van den Ende 1998) and LR5 (Vilgalys & Hester 1990) were used to amplify part (ITS) of the nuclear rDNA operon spanning the 3’ end of the 18S rRNA gene, the first internal transcribed spacer (ITS1), the 5.8S rRNA gene, the second ITS region (ITS2) and ± 900 bp of the 5’ end of the 28S rRNA gene. The primers ITS4 (White et al. 1990) and LSU1Fd (Crous et al. 2009a) were used as internal sequence primers to ensure good quality sequences over the entire length of the amplicon. Part of the beta-tubulin gene region (BTUB) was amplified and sequenced using primers Btub526F and Btub1332R (Jewell & Hsiang 2013), and primers RPB150F (Jewell & Hsiang 2013) and fRPB2-7cR (Liu et al. 1999) were used for the RNA polymerase II second largest subunit gene (RPB2). Amplification conditions for ITS and LSU followed Crous et al. (2013) and for BTUB and RPB2 Jewell & Hsiang (2013). The program SeqMan Pro (DNASTAR, Madison, WI, USA) was used to obtain consensus sequences of each isolate. Megablast searches using ITS and LSU sequences were performed against NCBIs GenBank nucleotide sequence database to identify the closest matching sequences, which were added to the sequences alignment. Sequences were aligned with MAFFT v. 7 (Katoh & Standley 2013) using the defaults settings and adjusted by hand in MEGA v. 6.06 (Tamura et al. 2013). To address the phylogenetic relationships among taxa, Bayesian inference (BI) using MrBayes v. 3.2.1 (Ronquist et al. 2012), and for maximum parsimony (MP) and neighbour-joining analysis with the Kimura 2-parameter and the HKY85 substitution model using PAUP v. 4.0b10 (Swofford 2003) were used as described by Crous et al. (2006). For parsimony analysis, alignment gaps were treated as a fifth character state with all characters unordered and of equal weight. The maximum parsimony analysis was performed with the heuristic search option with 100 random taxa additions and tree bisection and reconstruction (TBR) as the branch-swapping algorithm. Branches of zero length were collapsed and all multiple, equally parsimonious trees were saved. Other measures calculated included tree length, consistency index, retention index and rescaled consistency index (TL, CI, RI and RC, respectively). MrModelTest v. 2.2 (Nylander 2004) was used to determine the best nucleotide substitution model settings prior to the Bayesian analysis in MrBayes v. 3.2.1 (Ronquist et al. 2012). Nodal support was assessed by bootstrap analysis from 1 000 replicates. Bootstrap values (BS) equal or higher than 70 % were considered significant. Posterior probabilities for the Bayesian analysis (PP) were determined by calculating 50 % majority rule consensus tree.

Sequences derived in this study were deposited at GenBank, the alignments and trees in TreeBASE (http://treebase.org/treebase-web/home.html). The phylogenetic trees were edited using FigTree v. 1.4.0 and Adobe Illustrator CS5.1.

Sordariomycetes, Hypocreales, Clavicipitaceae

Ephelis tripsaci (D. Mulder & Arx) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811868; Fig. 3

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Fig. 3

Ephelis tripsaci (from ex-type, CBS 857.72). a. Colony on OA at 25 °C in 3 wk; b, c. colony overview; d, e. sporodochia; f. extracellular pigments and crystals; g–j. conidiogenous cells; k. conidia. — Scale bars: d, e = 100 μm; f–k = 10 μm.

Basionym. Microdochium tripsaci D. Mulder & Arx, Sydowia 34: 32. 1981.

Mycelium immersed or superficial, hyphae branched, septate, hyaline. Sporodochia white buff to olivaceous black, 276–510 μm diam, solitary to aggregated, often confluent at base, textura intricata-epidermoidea, 1.5–4 μm diam; hymenium with hyaline to pale brown cells, dark sporodochia with crystals (white to yellow) and extracellular brown pigments (umber to chestnut). Conidiophores branched, hyaline, smooth. Conidiogenous cells holoblastic, sympodial, terminal or lateral on aerial mycelium, straight or flexuous, cylindrical, 13–86 × 1–2 μm, hyaline. Conidia in whorls at the tips of conidiogenous cells, acicular, vermiform-subulate or obclavate, 12–22.5 × 1.5–3 μm, unicellular, hyaline, smooth-walled, apically rostrate and curved, base truncate, 1 μm diam.

Culture characteristics — Colonies on OA reaching 12–14 mm diam in 3 wk, velvety to powdery, white, margin with rhizoids. Sporodochia formed after 2 wk near the inoculum, vinaceous buff to grey olivaceous.

Specimen examined. SRI LANKA, on leaf sheath in Tripsacum laxum, Oct. 1972, D. Mulder (holotype CBS H-22144; living culture ex-type CBS 857.72).

Notes — The isolate CBS 857.72 groups in a clade with Ephelis oryzae CBS 236.64 and other members of Clavicipitaceae (Fig. 1). Ephelis tripsaci was initially included in Microdochium. Nevertheless, the isolate CBS 857.72 fits with the Ephelis concept, based on molecular and morphological data. Blast search of ITS resulted in a 99 % of similarity with AB038564 of Ephelis japonica, CBS 236.64 of Ephelis oryzae and several other unidentified Ephelis spp. Conidial morphology in E. tripsaci is slightly different from E. japonica and E. oryzae, having shorter and wider conidia (in E. japonica they are 20–30 × 0.7–1 μm, and in E. oryzae 20–35 × 1 μm, in E. tripsaci 12–22.5 × 1.5–3 μm). Ephelis has been reported as asexual morph occurring in different genera in Clavicipitaceae (Hypocreales) mainly in Atkinsonella, Balansia, Myriogenispora and Nigrocornus (Kuldau et al. 1997, White et al. 2003, Seifert et al. 2011). Phylogenetic studies demonstrated that species of Atkinsonella, Balansia and Myriogenispora with Ephelis asexual states form a monophyletic clade (Kuldau et al. 1997). Further taxonomic studies are clearly needed on these genera.

Sordariomycetes, incertae sedis

Paramicrodochium Hern.-Restr. & Crous, gen. nov. — MycoBank MB811869

Etymology. Named after its morphological similarity to, but being distinct from, Microdochium.

Type species. Paramicrodochium gracile (Mouch. & Samson) Hern.-Restr. & Crous.

Mycelium immersed and superficial, hyphae hyaline, septate, smooth. Conidiophores slightly differentiated, branched, hyaline. Conidiogenous cells polyblastic, occasionally monoblastic, terminal and intercalary, sympodial, denticulate, cylindrical, lageniform, straight or curved. Conidia solitary, dry, hyaline, unicellular, smooth, filiform to falcate, straight or curved, truncate at base, tapering towards the apex. Sexual morph unknown.

Paramicrodochium gracile (Mouch. & Samson) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811870; Fig. 4

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Fig. 4

Paramicrodochium gracile (from ex-type, CBS 493.70). a. Colony on OA at 25 °C in 4 wk; b–f. conidiogenous cells; g. conidia. — Scale bars: b–g = 10 μm.

Basionym. Microdochium gracile Mouch. & Samson, Rev. Mycol. (Paris) 37: 270. 1973.

Mycelium immersed and superficial, hyphae septate, hyaline. Conidiogenous cells mainly terminal, mono- and polyblastic, denticulate, straight or curved, cylindrical to slightly inflated in the median region, 7–31.5 × 1.5–3 μm, hyaline, smooth. Conidia acicular, falcate, 11–18 × 0.8–1.5 μm, unicellular, hyaline, apex pointed, base truncate.

Culture characteristics — Colonies on OA 20 mm diam in 4 wk. Flat, aerial mycelium absent, with concentric rings, flesh to white at the periphery, margin entire; reverse saffron. On MEA, 25–30 mm diam after 4 wk. Convex, funiculose, peach, margin fimbriate; reverse scarlet.

Specimen examined. THE NETHERLANDS, Baarn, Groeneveld, isolated from rabbit dung, 1970, G.S. de Hoog, (CBS H-22138, living culture ex-type CBS 493.70 (as Microdochium gracile).

Notes — The strain CBS 493.70 grouped incertae sedis (Sordariomycetes) in a clade distant from Xylariales. Paramicrodochium is introduced here to accommodate a microdochium-like taxon isolated from a rabbit dung sample collected in The Netherlands. According to the phylogenetic analysis this taxon does not cluster with Microdochium s.str. Paramicrodochium gracile was placed as the sister clade of Lanspora coronata, Paramicrothyrium chinensis and Phomatospora bellaminuta. These obscure fungi are sexual morphs without any known asexual morph. Paramicrothyrium chinenses is a fungus that grows on dead leaves found in China and produces thyrothecial ascomata (Wu et al. 2011). Lanspora coronata is a marine species that grows on driftwood collected in Seychelles (Hyde & Jones 1986). Phomatospora bellaminuta was isolated from senescent culms of Juncus roemerianus in North Carolina (USA) and also considered a marine fungus (Kohlmeyer et al. 1995). Additional samples are needed in order to assess the higher taxonomical rank and to understand the ecology and geographic distribution of species in this clade.

Sordariomycetes, Xylariales

Microdochiaceae Hern.-Restr., Crous & J.Z. Groenew., fam. nov. — MycoBank MB811871

Saprobic, endophytic or pathogenic; on leaves, seeds and soil. Sexual morph. Stroma present or absent. Ascomata perithecial. Asci cylindrical, oblong, clavate, with amyloid funnel-shaped apical ring and 8 biseriate or uniseriate ascospores. Ascospores ellipsoid or oblong, fusoid, hyaline to pale brown. Asexual morph. Conidiomata if present, sporodochial. Conidiophores solitary or aggregated, mono- or biverticillate. Conidiogenous cells solitary or in whorls, polyblastic, sympodial, denticulate, cylindrical often ampulliform, lageniform with elongated necks and minute annellides from percurrent proliferations, hyaline to pale brown. Conidia lunate, oblong, fusiform or cylindrical, straight or curved, hyaline, flattened at base. Chlamydospores if present, brown.

Type genus. Microdochium Syd.

Included genera — Idriella, Microdochium and Selenodriella.

Idriella P.E. Nelson & S. Wilh., Mycologia 48: 550. 1956

Mycelium immersed and superficial, hyphae hyaline to brown, septate, smooth. Conidiophores brown, non-septate. Conidiogenous cells polyblastic, terminal, denticulate, lageniform to cylindrical. Conidia dry, in heads, hyaline, unicellular, smooth, lunate, curved. Chlamydospores brown, uni- or pluricellular. Sexual morph unknown.

Type species. Idriella lunata P.E. Nelson & S. Wilh.

Idriella lunata P.E. Nelson & S. Wilh., Mycologia 48: 550. 1956 — Fig. 5

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Fig. 5

Idriella lunata (a–d, j from ex-type CBS 204.56; e from CBS 177.57; g–i, k from CBS 404.78). a. Colony overview on OA at 25 °C in 3 wk; b–f. conidiogenous cells; g–i. chlamydospores; j, k. conidia. — Scale bars: b–k = 10 μm.

Specimens examined. JAPAN, Kamakura, unknown substrate, Dec. 1974, K. Takano, living culture CBS 736.74. – THE NETHERLANDS, isolated from soil, Oct. 1960, J.C. Went, living culture CBS 209.60. – UNKNOWN, unknown substrate, 12 Jan. 1957, P.E. Nelson, living culture CBS 177.57. – USA, Santa Clara, California, on diseased roots of Fragaria chiloensis, Sept. 1950, P.E. Nelson, living culture ex-type CBS 204.56.

Notes — Idriella lunata was introduced for a fungus growing on infected roots on Fragaria chiloensis (Nelson & Wilhelm 1956) and the genus currently comprises 30 species (Matsushima 1971, Von Arx 1981, Castañeda-Ruiz & Kendrick 1991, Rodrigues & Samuels 1992). Nevertheless, our phylogenetic analyses suggest that Idriella is a monotypic genus, and species formerly described in this genus as I. desertorum, I. jambosae and I. uncinospora, depict new genera. Although the phylogenetic position of these new genera is still unclear, they do not belong to the Microdochiaceae, but appear as members of Sordariomycetes with uncertain position (Fig. 1).

Microdochium Syd., Ann. Mycol. 22: 267. 1924

=Monographella Petr., Ann. Mycol. 22: 144. 1924.

=Griphosphaerella Petr., Ann. Mycol. 25: 209. 1927.

=Gloeocercospora D.C. Bain & Edgerton, Trans. Brit. Mycol. Soc. 57: 358. 1971.

=Gerlachia W. Gams & E. Müll., Netherlands J. Agric. Sci. 86: 49. 1980.

Type species. Microdochium phragmitis Syd.

Mycelium immersed, branched, septate, hyphae hyaline to pale brown. Sporodochia, if present, epidermal, subepidermal, erumpent through stomata, through rupture of the outer epidermal wall and cuticle, or by specialized egression hyphae through the outer epidermal wall; hyaline, pseudoparenchymatic, spreading after egress. Conidiophores more or less verticillate, often slightly differentiated, reduced to conidiogenous cells, hyaline, smooth. Conidiogenous cells holoblastic, discrete, hyaline, smooth, solitary or aggregated in small sporodochia. Two kinds: with sympodial proliferation, cylindrical or slightly tapering, or clavate, denticulate with one or more apical denticles. Or with percurrent proliferation (annellidic), subcylindrical, obpyriform, ampulliform to lageniform. Conidia dry or in slimy mass, unicellular or multiseptate, hyaline, smooth, lunate, falcate, fusiform, filiform, obovoid or subpyriform, straight or curved, apex rounded, base flattened. Sometimes the conidia originate directly from hyphae. Chlamydospores terminal or intercalary, solitary, in chains or grouped in clusters, brown. Sexual morph monographella-like, on natural substrate. Ascomata perithecial, immersed, subepidermal, solitary or in groups, pale brown to black, globose, subglobose to oval with central, papillate and often acute ostiole, ostioles usually more distinctly pigmented than the perithecial body, filled with slightly clavate periphyses. Peridium brown, thin-walled, thickened and darker around the ostiole, in view face textura angularis-epidermoidea. Paraphyses filamentous, apically free, thin-walled. Asci unitunicate, oblong to clavate with 8 bi- to multiseriate ascospores, apex with an amyloid, refractive, flat, funnel-shaped ring. Ascospores clavate, fusoid or oblong, hyaline to brownish, straight or curved, smooth and septate.

Microdochium albescens (Thüm.) Hern.-Restr. & Crous, comb. nov. — MycoBank MB812167

Basionym. Metasphaeria albescens Thüm., Die Pilze der Reispflanze 12: 5. 1889.

≡ Griphosphaerella albescens (Thüm.) Arx, Gen. Fungi Sporul. Cult., Edn 3 (Vaduz): 174. 1981.

≡ Monographella albescens (Thüm.) V.O. Parkinson, Sivan. & C. Booth, Trans. Brit. Mycol. Soc. 76: 64. 1981.

=Metasphaeria oryzae-sativae Hara, Diseases of the Rice Plant (Japan): 151. 1918.

=Rhynchosporium oryzae Hashioka & Yokogi, Contrib. Lab. Plant Disease Sci. Fac. Agric. Gifu Univ. 6: 51. 1955.

≡ Gerlachia oryzae (Hashioka & Yokogi) W. Gams, in Gams & Müller, Neth. J. Pl. Path. 86: 50. 1980.

≡ Microdochium oryzae (Hashioka & Yokogi) Samuels & I.C. Hallett, Trans. Brit. Mycol. Soc. 81: 481. 1983.

=Micronectriella pavgii R.A. Singh, Friesia 11: 238. 1978.

Microdochium citrinidiscum Hern.-Restr. & Crous, sp. nov. — MycoBank MB811872; Fig. 6

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Fig. 6

Microdochium citrinidiscum (from ex-type, CBS 109067). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c–e. conidiogenous cells; f, g. conidia. — Scale bars: c–g = 10 μm.

Etymology. Latin Citrinus- meaning orange and discus- disk; in reference to their orange slice colony appearance.

Mycelium mostly immersed, hyphae hyaline, septate, smooth, 1.5–4 μm wide. Conidiophores undifferentiated. Conidiogenous cells terminal or intercalary, mono- or polyblastic, denticulate, cylindrical, 11–29 × 1.5–2 μm. Conidia cylindrical, clavate, obovoid, 0–3-septate, 7–31 × 2–3 μm, base usually flattened 0.5–1 μm. Sometimes born directly from the mycelial hyphae. Chlamydospores not observed.

Culture characteristics — Colonies on OA 40 mm diam after 1 wk, centre aerial mycelium cottony, white, periphery scarce aerial mycelium, saffron, margin diffuse, reverse saffron, no exudate or soluble pigment produced. After 3 wk radially folded to rugose, shiny, dark saffron, margin diffuse, reverse cinnamon.

Specimen examined. PERU, Ucayali, Yarinacocha, Isla de Amor, on leaf of Eichhornia crassipes, 21 Oct. 1998, H.C. Evans, isolated by D.H. Djeddour (No. W1916f) (holotype CBS H-22132; living culture ex-type CBS 109067).

Notes — This species forms a clade with CBS 691.96 (listed in the CBS database as M. sorghi, not an ex-type culture). Unfortunately, the latter isolate remains sterile and only produces black sclerotia in culture. Microdochium sorghi is a widespread fungus that causes zonate leaf spots on Sorghum and other species of Poaceae. Microdochium sorghi is different from M. citrinidiscum in having larger conidia (50–125 × 1–3 μm, in culture) with up to 10 septa. Furthermore, it is characterized by producing sclerotial bodies in both natural substratum and in culture (Von Arx 1987, Braun 1995). In contrast, M. citrinidiscum is only known from Peru growing on leaves of Eichhornia crassipes, has smaller conidia (7–31 × 2–3 μm) with up to 3 septae, and lacks sclerotia in culture.

Microdochium colombiense Hern.-Restr. & Crous, sp. nov. — MycoBank MB811873; Fig. 7

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Fig. 7

Microdochium colombiense (from ex-type, CBS 624.94). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c–f. conidiogenous cells ampulliform with percurrent proliferations; g–i. conidiogenous cells cylindrical to clavate; j. conidia. — Scale bars: c–j = 10 μm.

Etymology. Named after the country where this fungus was collected, Colombia.

Mycelium mostly immersed; hyphae hyaline, septate, 1.5–2.5 μm wide. Conidiogenous cells of two types: some polyblastic, ampulliform, with percurrent proliferations, 5–11.5 × 2.5–3.5 μm, neck up to 4.5 μm long, 1–1.5 μm wide, others cylindrical up to 13 μm long, 1–2 μm wide. Conidia lunate, fusiform, allantoid or reniform, straight or curved, 5–8 × 1.5–2.5 μm, 0(–1)-septate, base truncate. Sometimes produced directly on mycelial hyphae. Chlamydospores not observed.

Culture characteristics — Colonies on OA 40 mm diam after 1 wk, flat, salmon, no exudate or soluble pigment produced, margin diffuse or entire; reverse saffron. After 3 wk 90 mm diam, flat, orange peach, radially striate.

Specimen examined. COLOMBIA, on Musa sapientum, Jan. 1995, L. Verbruggen (holotype CBS H-22133; living culture ex-type CBS 624.94).

Notes — Microdochium colombiense forms a sister clade to M. nivale and M. majus, and is morphologically distinguished from those species by their conidial morphology. Microdochium colombiense has smaller conidia (5–8 × 1.5–2.6 μm) than those of M. majus (6–15 × 2–4 μm) and M. nivale (5–36 × 2–4.5 μm). Furthermore, conidia in M. colombiense are mostly aseptate (rarely 1-septate), while in M. majus and M. nivale conidia are mostly 3-septate (up to 10- or 7-septate, respectively). Although M. colombiense resembles M. neoqueenslandicum, they are phylogenetically distinct (Fig. 2). Additionally, the colony growth rate at 30 °C after 1 wk was about 10 mm in M. colombiense (CBS 624.94) and 35–37 mm in M. neoqueenslandicum (CBS 445.95 and CBS 108926) under the same conditions. At lower temperatures (12, 18 and 24 °C) the grow rate was similar for both species.

Microdochium consociatum (Rehm) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811967

Basionym. Leptosphaeria consociata Rehm, Hedwigia Beibl.: 149. 1896.

= Monographella consociata (Rehm) O.E. Erikss. & J.Z. Yue, Mycotaxon 38: 205. 1990.

Microdochium fisheri Hern.-Restr. & Crous, sp. nov. — MycoBank MB811874; Fig. 8

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Fig. 8

Microdochium fisheri (from ex-type, CBS 242.91). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c, d. conidiophores; e–g. conidiogenous cells; h. conidia. — Scale bars: c–h = 10 μm.

Etymology. Named in honour of P.J. Fisher, who collected this fungus in the UK.

Mycelium superficial and immersed; hyphae hyaline, branched, septate. Conidiophores slightly differentiated, bifurcate, hyaline, smooth. Conidiogenous cells terminal, sympodial, denticulate, cylindrical, 19–60 × 1.5–2 μm, hyaline, smooth. Conidia solitary, dry, fusiform, obovoid, subpyriform, to clavate, 7–12 × 3–4 μm, 0–1-septate, hyaline, tapering to a subtruncate hilum; hilum unpigmented. Chlamydospores not observed.

Culture characteristics — Colonies on OA 45–50 mm diam after 1 wk, powdery to velvety, aerial sporulation, centre salmon, periphery peach, margin entire; reverse salmon.

Specimen examined. UK, on stem of Oryza sativa (greenhouse-grown plant, endophytic), June 1990, P.J. Fisher (holotype CBS H-22142; living culture ex-type CBS 242.90).

Notes — Isolate CBS 242.90 forms a separated branch as the sister clade of M. phragmites and M. lycopodinum. Originally, the isolate CBS 242.90 was identified as Arthrobotrys foliicola (no ex-type isolate available) which is morphologically similar, but A. foliicola was originally described with pale brown, sympodial, and nodose proliferations in the conidiophores, terminal and intercalary, swollen conidiogenous cells, hyaline conidia with brown septa, appearing pale brown in mass (Matsushima 1975). Microdochium fisheri is different since it has hyaline, tapering conidiophores, with denticulate conidiogenous cells and hyaline conidia, without pigment at the septa, appearing salmon in mass.

Microdochium fusariisporum (Ellis & Everh.) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811968

Basionym. Rhopographus fusariisporus Ellis & Everh., Erythea 2: 23. 1894.

≡ Exarmidium fusariisporum (Ellis & Everh.) Theiss. & Syd., Ann. Mycol. 13: 424. 1915.

≡ Monographella fusariispora (Ellis & Everh.) M.E. Barr, Mycotaxon 46: 63. 1993.

Microdochium lycopodinum (Jaklitsch, Siepe & Voglmayr) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811969; Fig. 9, ​,1010

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Fig. 9

Microdochium lycopodinum (from CBS 109398). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c. colony overview; d–f. aggregated conidiophores; g, h. conidiogenous cells; i. conidia. — Scale bars: d = 25 μm; e–i = 10 μm.

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Fig. 10

Microdochium lycopodinum (from CBS 109399). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c. colony overview; d. sporodochia with brown mycelium; e, f. aggregated conidiophores; g, h. conidiogenous cells; i. conidia. — Scale bars: d = 100 μm; e–i = 10 μm.

Basionym. Monographella lycopodina Jaklitsch, Siepe & Voglmayr, Fung. Diversity 52: 86. 2012.

Description of sexual morph — Jaklitsch & Volgmayr (2012).

Mycelium immersed and superficial, hyphae hyaline to pale brown, septate, smooth or verruculose, 1.5–6 μm diam. Conidiophores more or less mono- to biverticillate, metulae doliiform to clavate, aggregated in slimy masses in the aerial mycelium often reduced to conidiogenous cells born directly from the hyphae. Conidiogenous cells holoblastic, with percurrent proliferations, ampulliform to lageniform, subcylindrical, 4–12 × 2.5–3.5 μm. Conidia hyaline, fusiform or with one side straighter than the other, lunate, 8–15.5 × 2.5–4 μm, 0–1-septate, truncate base, rounded apex. Some conidia are borne directly on the mycelial hyphae. Chlamydospores not observed. Sclerotia superficial on the agar, brown to dark brown, textura angularis.

Culture characteristics — Colonies on OA reaching 50–54 mm after 1 wk. White cottony, lanose to flocosse, buff to rosy buff, margin effuse. After 3 wk with aerial mycelium profuse, olivaceous grey with some white to saffron patches, aerial sporulation in aggregated slimy masses, rosy buff to umber; reverse greenish black with some white patches.

Specimens examined. AUSTRIA, Oberösterreich, St. Willibald, Salletwald, on leaves of Lycopodium annotinum, 19 July 2009, H. Voglmayr (living culture ex-type CBS 125585). – GERMANY, Konstanz, on Phragmites australis, May 1997, W. Leibinger, living cultures CBS 109397, CBS 109398, CBS 109399. – THE NETHERLANDS, Sellingen, isolated from an air sample, Dec. 1967, A. Kikstra (No. 1062), living culture CBS 146.68.

Notes — The clade M. lycopodinum is represented by five isolates with M. phragmitis as sister clade. The ex-type culture of M. lycopodinum, CBS 122885, and CBS 146.68 remained sterile. Isolate CBS 109397 was morphologically degenerated, as colonies lacked aerial mycelium and sporodochia, conidiogenous cells were scarce and small, and sclerotial bodies were present. The other two strains, CBS 109398 and CBS 109399 (Fig. 9, ​,10),10), showed colonies with abundant aerial mycelium, producing superficial sporodochial-like structures, with verticillate conidiophores and abundant conidiogenous cells and conidia. Microdochium lycopodinum was originally described as sexual morph growing in leaves of Lycopodium annotium in Austria and Germany (Jaklitsch & Volgmayr 2012). Nevertheless, original cultures were sterile and no asexual morph has been reported. According to our phylogenetic analysis based in four genes (Fig. 2), isolates CBS 146.68, CBS 109397, CBS 109398 and CBS 109399 represent the same phylogenetic species as M. lycopodinum. Here we newly describe the asexual morph of M. lycopodinum.

Microdochium maydis (E. Müll. & Samuels) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811970

Basionym. Monographella maydis E. Müll. & Samuels, Nova Hedwigia 40: 114. 1984.

Microdochium neoqueenslandicum Hern.-Restr. & Crous, sp. nov. — MycoBank MB811875; Fig. 11

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Fig. 11

Microdochium neoqueenslandicum (from ex-type, CBS 108926). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c. colony overview; d. sporodochia; e–h. conidiophores with conidiogenous cells; i. conidia. — Scale bars: d = 25 μm; e–i = 10 μm.

Etymology. Named after its resemblance to Microdochium queenslandicum.

Mycelium immersed or superficial, hyphae hyaline, septate, smooth. Sporodochia slimy, orange. Conidiophores more or less mono- or biverticillate, metulae clavate to cylindrical. Conidiogenous cells polyblastic, with percurrent proliferations, ampulliform, lageniform to subcylindrical, 4.5–10 × 2–3.5 μm, neck up to 4 μm long, 1–1.5 μm diam, solitary or in whorls. Conidia lunate, allantoid, curved, with one side straighter than the other, 0(–1)-septate, 4–9 × 1.5–3 μm, base flattened. Sometimes produced directly on the mycelial hyphae. Chlamydospores not observed.

Culture characteristics — Colonies on OA 40–47 mm diam after 1 wk, centre flat, creamy, with concentric rings, peach to salmon, periphery with cottony aerial mycelium, white, margin diffuse, entire. After 3 wk with concentric rings scarlet of sporodochia, alternate with a dense zone of white, cottony aerial mycelium, exudate hyaline. No aerial mycelium nor sporodochia were observed in degenerated cultures.

Specimens examined. NEW ZEALAND, Waihi, Waihi Golf Club, on Agrostis sp., 24 Jan. 2000, A. Ellis (Holotype CBS H-22136; living culture ex-type CBS 108926). – THE NETHERLANDS, Brecklenkamp, Twente, on Juncus effusus, 6 Apr. 1995, E. Brouwer, living culture CBS 445.95.

Notes — Microdochium neoqueenslandicum is represented by two isolates, CBS 108926 and CBS 445.95, and clustered basal to other Microdochium species (Fig. 2). Microdochium neoqueenslandicum is distinct from M. queenslandicum by having shorter and wider conidia (7.5–11 × 1.8–2.2 μm in M. queenslandicum). Microdochium queenslandicum is only known from a forest soil sample collected in Australia. Unfortunately, no living material of M. queenslandicum was available for study. In our phylogenetic tree M. neoqueenslandicum is represented by two strains isolated from grasses, Agrostis sp. and Juncus effuses, the former from New Zealand and the latter from the Netherlands, suggesting that this species has a wide distribution. The isolate CBS 445.95 was macro- and micromorphologically degenerated, since colonies lacked aerial mycelium and sporodochia, and conidiogenous cells were scarce and smaller in size.

Microdochium opuntiae (Ellis & Everh.) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811971

Basionym. Sphaerella opuntiae Ellis & Everh., J. Mycol. 4: 97. 1888.

≡ Mycosphaerella opuntiae (Ellis & Everh.) Dearn., Bull. New York State Mus. Nat. Hist. 205: 55. 1919.

≡ Monographella opuntiae (Ellis & Everh.) Arx, Trans. Brit. Mycol. Soc. 83: 374. 1984.

= Gloeosporium lunatum Ellis & Everh., Proc. Acad. Nat. Sci. Philadelphia 43: 82. 1891.

≡ Fusarium lunatum (Ellis & Everh.) Arx, Verh. Kon. Ned. Akad. Wetensch., Afd. Natuurk., sect. 2. 51: 101. 1957.

Microdochium phragmitis Syd., Ann. Mycol. 22: 267. 1924 — Fig. 12, ​,1313

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Fig. 12

Microdochium phragmitis (from ex-epitype, CBS 285.71). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c. colony overview; d–h. conidiogenous cells; i. conidia. — Scale bars: d–i = 10 μm.

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Fig. 13

Microdochium phragmitis (from CBS 423.78). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c, d. colony overview with orange, slimy sporodochia; e–g. sporodochia; h, i. conidiophores with conidiogenous cells; j, k. conidia. — Scale bars: e = 50 μm; f–k = 10 μm.

Description based on CBS 285.71 after 1 wk on OA at 24 °C. Mycelium superficial and immersed, hyphae hyaline, septate, 1–2 μm wide. Conidiogenous cells terminal, sympodial, denticulate, hyaline, smooth, cylindrical to clavate, sometimes navicular, 6–24 × 1.5–3 μm. Conidia dry, solitary, fusiform, navicular or clavate, 0–1-septate, 10–14.5 × 2–3 μm, guttulate. Chlamydospores not observed.

Culture characteristics — Colonies on OA 37 mm diam after 1 wk. Floccose, white in the centre, sparse aerial mycelium, buff to the periphery, margin effuse; reverse buff. After 3 wk velvety.

Specimens examined. GERMANY, Berlin, Brandenburg, on leaves of Phragmites communis, Nov. 1919, H. Sydow (holotype K-IMI 193888; Sydow, Mycotheca germanica 2250). – POLAND, Bialowiesza National Park, on Phragmites australis, Sept. 1966, W. Gams (epitype designated here CBS H-22135, MBT200934, living culture ex-epitype CBS 285.71). – THE NETHERLANDS, Nijkerk, on a leaf of Phragmites australis, unknown date, P. Reinecke, CBS H-22134, CBS 423.78 living culture.

Notes — The ex-epitype strain CBS 285.71 and CBS 423.78 clustered together (1 PP) in the combined tree (Fig. 2). Nevertheless, the strain CBS 423.78 (Fig. 13) differs from the ex-epitype strain CBS 285.71 (Fig. 12) in its colony appearance and micro-morphological characters. CBS 423.78 produces pionnotal sporodochia, conidiogenous cells lageniform with annellidic percurrent proliferations, conidia produced in slimy mass, fusiform, 12.5–16 × 3–3.5 μm and obovoid, unicellular, 4.5–8.5 × 2–4 μm. Molecularly those strains were very similar, their ITS sequences were identical and the other genes only differ in 5, 3 and 1 bp in their BTUB, RPB2 and LSU sequences, respectively, which would indicate they are the same phylogenetic species. Considering the polymorphism in Microdochium and the difficulties to delimit species in this group we refer to CBS 423.78 as M. phragmites.

Microdochium seminicola Hern.-Restr., Seifert, Clear & B. Dorn, sp. nov. — MycoBank MB812168; Fig. 14

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Fig. 14

Microdochium seminicola (from ex-type, CBS 139951). a. Colony on OA at 25 °C in 3 wk; b. colony overview of the sporodochia; c. colony overview of the ascomata; d. sporodochia; e–g. conidiophores with conidiogenous cells and conidia attached; h. conidia; i. ascomata; j–l. asci (k and m in Melzer’ reagent); m. ascus ring in Melzer’s reagent; n. ascospores — Scale bars: d–h; j–n = 10 μm; i = 50 μm.

Etymology. Latin seminicola- meaning growing on seeds.

Mycelium immersed and superficial, hyphae hyaline, septate, smooth. Sporodochia slimy, peach, minute to essentially pionnotal. Conidiophores more or less biverticillate, metulae doliiform. Conidiogenous cells solitary or in whorls, ampulliform to lageniform, with percurrent proliferations, 5–11 × 3–4 μm, the neck 1–1.5 μm wide. Conidia cylindrical to fusiform, straight or curved, 19–54 × 3–4.5 μm, (0–)3(–5)-septate, hyaline, tapering at the apex, occasionally curved at the tip, base usually flattened. Chlamydospores not observed. Sexual morph. Perithecia submerged or superficial on the agar, solitary or in groups, spherical to subspherical, 110–149 μm diam, pale brown to brown, textura angularis-epidermoidea. Paraphyses filiform, hyaline. Asci basal, 41–66.5 × 7.5–11 μm, oblong, narrowly clavate, fusiform, with 8 ascospores, short stipe and amyloid, funnel-shaped apical ring. Ascospores fusiform, oblong, sometimes navicular or allantoid, 12–22 × 3–5 μm, 0–3-septate, not constricted at the septa, hyaline, smooth.

Culture characteristics — Colonies on OA 90 mm diam after 1 wk, centre with some puffs of white aerial mycelium, periphery scarce aerial mycelium, salmon to saffron with slimy, peach spots, reverse similar; no exudate or soluble pigment produced. After 3 wk centre with some puffs of white aerial mycelium, saffron with slimy, peach, brick or dark brick spots.

Specimens examined. CANADA, Alberta, on barley, 1995, R. Clear, DAOM 250164; Manitoba, on grain, 2001, R. Clear, DAOM 250175, DAOM 250174, DAOM 250173, DAOM 250172, DAOM 250171, DAOM 250169, CPC 26001; Manitoba, Brandon, on Triticum aestivum, 2006, DAOM 250162, DAOM 250161; Saskatchewan, on grain, 1984, R. Clear, CPC 25993; Saskatchewan, on grain, 2001, R. Clear, DAOM 250168, DAOM 250167, DAOM 250166, DAOM 250165; Saskatchewan, on Triticum aestivum, 10 Jan. 2002, R. Clear, DAOM 250176; unknown substrate, 16 June 2005, R. Clear, DAOM 250163. – SWITZERLAND, Reckenholz, on maize kernels, 2005, B. Dorn (holotype CBS H-22139; living culture ex-type CBS 139951 = CPC 26019); 2006, B. Dorn, DAOM 250159, DAOM 250158; 2007, B. Dorn, DAOM 250155; unknown date, B. Dorn, CBS 122706, CBS 122707.

Notes — The M. seminicola clade is represented by 23 strains collected mainly in Canada and Switzerland. Most strains remained sterile. Conidiophores and conidia observed in CBS 139951 and CBS 122706 were very similar. The sexual morph was only observed in CBS 139951. Microdochium seminicola was phylogenetically closely related to M. albescens (Fig. 2). Nevertheless, M. albescens, the causal agent of leaf-scald disease of rice, is different from M. seminicola. Microdochium albescens has larger ascospores with more septa (14–30 × 3.5–7.5 μm, 1–5-septate), and the asexual morph has falcate conidia, 11–16 × 3.5–4.5 μm conidia that are 0–3-septate but usually 1-septate, (Parkinson et al. 1981) while M. seminicola has smaller ascospores with fewer septa (12–22 × 3–5 μm, up to 3-septate), and the asexual morph has larger conidia with more septa (23–54 μm long, up to 5-septate, usually 3-septate). Morphologically M. seminicola, which has been isolated from maize in Switzerland, also resembles M. maydis. However, conidia of M. maydis are smaller with more septa (20–46 × 3–4 μm, 3–9-septate). In addition, M. maydis was isolated from maize leaves whereas, although M. seminicola occurs on maize kernels, it is most often isolated from harvested grain, including oats, barley, and wheat grain, and rarely canola seed. Unfortunately, there are no cultures or molecular data available for M. maydis.

For decades, Canadian seed testing laboratories have been puzzled by the sporadic occurrence, sometimes at frequencies of 3–4 % within a seed lot, of this fast growing fungus, with white to pinkish colonies that superficially resemble those produced by some Fusarium species. However, the colonies often remain sterile on PDA, the medium used in most seed testing procedures. A few orange sporodochia are sometimes produced, but this sporulation disappears after one or two transfers, resulting in sterile, relatively fast-growing light orange colonies.

Microdochium stevensonii (Petr.) Hern.-Restr. & Crous, comb. nov. — MycoBank MB811972

Basionym. Griphosphaerella stevensonii Petr., Ann. Mycol. 25: 209. 1927.

≡ Griphosphaeria stevensonii (Petr.) E. Müll. & Arx, Phytopathol. Z. 24: 355. 1955.

≡ Monographella stevensonii (Petr.) Arx, The genera of fungi sporulating in pure culture: 174. 1981.

Microdochium trichocladiopsis Hern.-Restr. & Crous, sp. nov. — MycoBank MB811876; Fig. 15

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Fig. 15

Microdochium trichocladiopsis (from ex-type, CBS 623.77). a. Colony on OA at 25 °C in 1 wk; b. colony on OA at 25 °C in 3 wk; c–h. conidiogenous cells; i. conidia; j, k. chlamydospores. — Scale bars: c–k = 10 μm.

Etymology. Trichocladiopsis, referring to the chlamydospores of this taxon that superficially resemble conidia of Trichocladium species.

Mycelium mostly immersed, hyphae hyaline, branched, smooth. Conidiogenous cells sparse, solitary, cylindrical to clavate, straight, often curved at the tip, hyaline, smooth, 4–37.5 × 2–3 μm. Conidia oblong, fusiform to obovoid, straight or curved, 6–18 × 2–3.5 μm, 0(–1)-septate, base usually flattened. Chlamydospores abundant, terminal, obovoid, pyriform to clavate, trichocladium-like, 1–3(–5)-septate, brown to dark brown, basal cells often paler, constricted at the septa, sometimes with a pale brown frill at the base.

Culture characteristics — Colonies on OA 80 mm diam after 1 wk, flat, lacking aerial mycelium, rosy buff, black near to the inoculum, margin diffuse, reverse similar. After 3 wk, centre with sparse to absent aerial mycelium, radially striate, dark grey olivaceous, periphery aerial mycelium floccose white, margin diffuse, saffron, reverse olivaceous grey with concentric rings of pale mouse grey.

Specimen examined. UNKNOWN COUNTRY, from rhizosphere of Triticum aestivum, unknown date, J.W.L. van Vuurde (holotype CBS H-22137; living culture ex-type CBS 623.77).

Notes — Isolate CBS 623.77 formed a clade with two isolates of M. tainanensis, CBS 269.76 and CBS 270.76. Both species are clearly distinguished morphologically. In M. tainanensis the conidia are lunate and smaller (10–15 × 2–3 μm), while M. trichocladiopsis produces oblong to fusiform and larger conidia (4–37.5 × 2–3 μm). Species in this clade (Fig. 2) are associated with roots and produce brown chlamydospores. Microdochium trichocladiopsis was isolated from the rhizosphere of Triticum aestivum and has chlamydospores with up to 5 septa, while both isolates of M. tainanense were isolated from roots of Saccharum officinarum, and have aseptate chlamydospores (De Hoog & Hermanides-Nijhof 1977).

Selenodriella cubensis Hern.-Restr. & Crous, sp. nov. — MycoBank MB811877; Fig. 16

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Fig. 16

Selenodriella cubensis (from ex-type, CBS 683.96). a. Colony on OA at 25 °C in 1 wk; b, d–f. conidiophores; c. conidia; g–j. conidiogenous cells. — Scale bars: b–j = 10 μm.

Etymology. Named after the country where this fungus was collected, Cuba.

Mycelium immersed and superficial, hyphae hyaline to pale brown, branched, septate, smooth. Conidiophores erect, setiform, branched at the apex, brown at the base, becoming hyaline at the apex, 49–87 × 2.5–4 μm. Conidiogenous cells cylindrical to lageniform, sympodial, denticulate, terminal, in whorls at the apex or solitary on the mycelial hyphae, hyaline to subhyaline, 13–39 × 2–4 μm. Conidia lunate, asymmetrical, 10–20 × 2–3 μm, unicellular, hyaline, smooth-walled, guttulate. Chlamydospores not observed. Sexual morph unknown.

Culture characteristics — Colonies on OA 17–19 mm diam in 1 wk. Zonate, velvety to powdery, buff in the centre; sparse aerial mycelium, umber towards the periphery; margin diffuse.

Specimen examined. CUBA, unknown substrate, June 1996, R.F. Castañeda (holotype INIFAT C96/30; living culture ex-type CBS 683.96; CBS H-22143 dry culture).

Notes — The isolate CBS 683.96, formerly identified as Idriella tropicalis, is better accommodated in Selenodriella, since it produces setiform conidiophores, and conidiogenous cells and branches are disposed in whorls along the main axis of setiform conidiophores as in species of Selenodriella. It differs from Idriella, which shows conidiophores reduced to conidiogenous cells. The only available strain of Selenodriella cubensis clustered phylogenetically close to Selenodriella fertilis (CBS 772.83) in Microdochiaceae. Selenodriella fertilis, the type species of the genus, and S. cubensis, differs mainly in the arrangement of the conidiogenous cells. In S. fertilis they are arising in groups in the middle part of the conidiophores (Pirozynski & Hodges 1973), while in S. cubensis the conidiogenous cells are disposed at the apex of the conidiophores. Conidial morphology is slightly different in both species; in S. cubensis conidia are pointed at both ends, while in S. fertilis they are flat at the base and rounded at the apex.

We thank Keith A. Seifert, Randy Clear and Lawrence Thomson for providing strains and for valuable information of M. seminicola, and the technical staff of the CBS, Arien van Iperen (cultures) and Mieke Starink-Willemse (DNA isolation, amplification and sequencing) for their invaluable assistance.