Taxonomy

Structures were mounted in lactic acid, and 30 measurements (× 1 000 magnification) determined wherever possible, with the extremes of spore measurements given in parentheses. Colony colours (surface and reverse) were assessed after 2-4 wk on OA and PDA at 25 °C in the dark, using the colour charts of Rayner (1970). All cultures obtained in this study are maintained in the CBS collection (Table 1). Nomenclatural novelties and descriptions were deposited in MycoBank (www.MycoBank.org).

Members of Chaetothyriales, Herpotrichiellaceae

Cladophialophora australiensis Crous & A.D. Hocking, sp. nov. MycoBank MB504525. Fig. 3.

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Fig. 3.

Cladophialophora australiensis (CBS 112793). A. Conidiophore. B-C. Subcylindrical ramoconidia, and ellipsoid conidia. Scale bar = 10 μm.

Etymology: Named after its country of origin, Australia.

Cladophialophorae carrionii similis, sed conidiis secundis majoribus, (7-)8-12(-15) × 3-4 μm.

In vitro: Mycelium consisting of branched, septate, smooth, pale brown, guttulate, 2-3 μm wide hyphae; hyphal coils not seen. Conidiophores dimorphic; macroconidiophores mononematous, subcylindrical, multi-septate, straight to curved, up to 150 μm long (including conidiogenous cells), and 4 μm wide, pale to medium brown, smooth, guttulate; microconidiophores integrated with hyphae, which terminate in subcylindrical conidiogenous cells that give rise to branched chains of conidia; conidiophores (including conidiogenous cells) up to 5-septate, 50 μm long, with terminal and lateral conidiogenous cells. Conidiogenous cells pale to medium brown, smooth, guttulate, terminal and lateral, subcylindrical, 20-35 × 2-3.5 μm, or reduced to indistinct subtruncate to truncate loci, scars up to 2 μm wide, mono- to polyblastic, proliferating sympodially, scars neither darkened, thickened, nor refractive. Conidia pale to medium brown, guttulate, smooth; ramoconidia subcylindrical, 0-1-septate, 20-35 × 2-3 μm, hila subtruncate, inconspicuous, up to 2 μm wide, giving rise to branched chains of conidia; conidia ellipsoid, pale brown, but becoming dark brown and thick-walled in older cultures, guttulate, tapering towards subtruncate terminal loci, 0-1-septate, occurring in chains of up to 20 conidia, (7-)8-12(-15) × 3-4 μm (older, dark brown conidia are ellipsoid, up to 5 μm wide).

Cultural characteristics: Colonies erumpent, somewhat spreading, margins crenate, feathery, aerial mycelium sparse; colonies on PDA olivaceous-grey to iron-grey (surface); reverse iron-grey; on OA and SNA olivaceous-grey. Colonies reaching 5 mm diam after 2 wk at 25 °C in the dark; colonies fertile. Not able to grow at 37 °C.

Specimen examined: Australia, isolated from apple juice, Dec. 1986, A.D. Hocking, holotype CBS H-19899, culture ex-type CBS 112793 = CPC 1377.

Notes: Cladophialophora australiensis is one of two novel species of Cladophialophora originally isolated from sports drinks in Australia. Cladophialophora spp. are commonly associated with human disorders (Honbo et al. 1984, de Hoog et al. 2000, Levin et al. 2004), and thus their occurrence in sports drinks is cause for concern. However, none of the new species described here had the ability to grow at 37 °C, and therefore it is not expected that they could pose a danger to humans. Comparing ITS diversity, the species shows more than 12 % difference to established pathogens such as C. carrionii and C. bantiana (Sacc.) de Hoog et al.

Cladophialophora chaetospira (Grove) Crous & Arzanlou, comb. nov. MycoBank MB504526. Fig. 4.

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Fig. 4.

Cladophialophora chaetospira (CBS 114747). A-C. Hyphae giving rise to conidiophores with catenulate conidia. D-F. Conidia become up to 3-septate, frequently remaining attached in chains. Scale bars = 10 μm.

Basionym: Septocylindrium chaetospira Grove, J. Bot. Lond. 24: 199. 1886.

• ≡ Septonema chaetospira (Grove) S. Hughes, Naturalist, London 840: 9. 1952.

• ≡ Heteroconium chaetospira (Grove) M.B. Ellis, in Ellis, More Dematiaceous Hyphomycetes: 64. 1976.

In vitro: Mycelium consisting of branched, septate, smooth, medium brown hyphae, 2-3.5 μm wide. Conidiophores reduced to conidiogenous cells, or a single supporting cell, 20-40 × 3-4 μm. Conidiogenous cells subcylindrical, erect, straight to irregularly curved, medium brown, smooth, 15-30 × 3-4 μm. Conidia in branched, acropetal chains with up to 30 conidia; subcylindrical to fusiform, medium brown, smooth, tapering slightly at subtruncate ends, 1(-3)-septate, thin-walled, becoming slightly constricted at septa of older conidia, (20-)25-30(-45) × 3-4(-5) μm; conidia remaining attached in long chains; hila neither thickened, nor darkened-refractive.

Cultural characteristics: Colonies erumpent, convex, spreading, with sparse to dense aerial mycelium; margins smooth, undulate; on PDA iron-grey (surface), margins olivaceous-black; reverse olivaceous-black; on OA olivaceous-grey in the middle due to fluffy aerial mycelium, iron-grey in wide outer margin; on SNA olivaceous-grey. Colonies reaching 12 mm diam after 2 wk on PDA at 25 °C in the dark. Not able to grow at 37 °C.

Specimens examined: China, Yunnan, Yiliang, isolated from Phyllostachys bambusoides (Gramineae), decaying bamboo, freshwater, 6 Jul. 2003, L. Cai, CBS 114747; China, Yunnan, stream in Kunming, isolated from bamboo wood, 15 Jun. 2003, C. Lei, CBS 115468. Denmark, isolated from roots of Picea abies (Pinaceae), isol. by D.S. Malla, CBS 491.70. Germany, Schleswig-Holstein, Kiel-Kitzeberg, isolated from wheat field soil, isol. by W. Gams, CBS 514.63 = ATCC 16274 = MUCL 8310.

Notes: Two cultures of Heteroconium chaetospira were originally deposited as Spadicoides minuta L. Cai, McKenzie & K.D. Hyde (Cai et al. 2004), but later found to represent Heteroconium chaetospira, a species commonly found on rotting wood in Europe (Ellis 1976). The genus Heteroconium Petr. has in recent years been used to name leaf spotting fungi with chains of brown, disarticulating conidia (Crous et al. 2006b), which have phylogenetic affinities to several orders, obviously being polyphyletic. The type species of Heteroconium, H. citharexyli Petr., is a plant pathogen on Cytharexylum (Petrak 1949) with hitherto unknown phylogenetic position. The fact that H. chaetospira is linked to the Chaetothyriales, was rather unexpected. The species appears to be similar to others placed in Cladophialophora by having short, lateral conidiogenous cells, and long chains of branched subcylindrical conidia that largely remain attached. It is, however, quite distinct from other members of Cladophialophora in having medium brown conidia, and in lacking the ellipsoid conidia observed in several species.

Cladophialophora hostae Crous, U. Braun & H.D. Shin, sp. nov. MycoBank MB504527. Figs ​Figs55-​-66.

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Fig. 5.

Cladophialophora hostae (CPC 10737). A-B. Conidiogenous loci (arrows). C. Hyphal coil. D-F. Branched conidial chains. G-H. Conidia. Scale bar = 10 μm.

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Fig. 6.

Cladophialophora hostae (CPC 10737). Branched conidial chains with ramoconidia and conidia. Scale bar = 10 μm.

Etymology: Epithet derived from the host genus, Hosta.

Cladophialophorae scillae similis, sed conidiophoris in vitro brevioribus et leniter angustioribus, 10-15 × 1.5-2 μm, conidiis brevioribus, (7-)10-15(-20) μm.

In vivo: Leaf spots amphigenous, subcircular to somewhat angular-irregular, 1-5 mm wide, scattered to aggregated, sometimes confluent, pale to medium brown or with a reddish brown tinge, later greyish brown, margin indefinite or on the upper leaf surface with a narrow slightly raised marginal line or very narrow lighter halo, yellowish, ochraceous to brownish. Caespituli epiphyllous, punctiform to confluent, dingy greyish brown. Mycelium immersed, forming fusicladium-like hyphal strands or plates; hyphae septate, sometimes with constrictions at the septa, thin-walled, pale olivaceous, 1.5-7 μm wide. Stromata immersed, small, 10-40 μm diam, composed of swollen hyphal cells, subcircular to somewhat angular-irregular in outline, 2-8 μm diam, wall somewhat thickened, brown. Conidiophores in small to moderately large fascicles, loose, divergent to moderately dense, rarely solitary, arising from stromatic hyphal aggregations, erumpent, erect, usually unbranched, rarely branched, straight, subcylindrical to distinctly geniculate-sinuous, 5-40 × 2-5 μm, 0-6-septate, pale to medium olivaceous to olivaceous-brown, thin-walled, up to 0.5 μm, smooth. Conidiogenous cells integrated, terminal, 5-15(-20) μm long, sympodial, conidiogenous loci rather inconspicuous to subdenticulate, flat-tipped, 1-1.5 μm diam, unthickened or almost so, not to slightly darkened-refractive. Conidia in simple or branched chains, narrowly ellipsoid-subcylindrical, 10-15 × 1.5-3.5 μm, 0-1-septate, subhyaline to pale olivaceous, thin-walled, smooth, ends truncate or with two denticle-like hila in ramoconidia, (0.75-)1-1.5(-2) μm diam, unthickened or almost so, at most slightly darkened-refractive.

In vitro: Mycelium composed of branched, smooth, pale olivaceous to medium brown hyphae, frequently forming hyphal coils, guttulate, septa inconspicuous, not constricted, hyphae somewhat irregular in width, 1-2 μm wide. Conidiophores reduced to conidiogenous cells, integrated in hyphae, terminal, subcylindrical, pale olivaceous to pale brown, smooth, 0-1-septate, proliferating sympodially at apex via 1-2(-3) flat-tipped, minute, denticle-like loci, 1-1.5 μm wide, 10-15 × 1.5-2 μm; scars minutely darkened and thickened, but not refractive. Conidia in extremely long chains (-60), simple or branched, subcylindrical, or narrowly ellipsoid, smooth, pale olivaceous, 0-1-septate, (7-)10-15(-20) × (1.5-)2(-2.5) μm, hila truncate, 1-1.5 μm wide, minutely thickened and darkened-refractive.

Cultural characteristics: Colonies on PDA erumpent, spreading, with smooth, undulate margins and dense aerial mycelium; surface hazel (middle), outer zone isabelline; reverse fuscous-black in middle, isabelline in outer zone. Colonies reaching 25 mm diam on SNA, and 40 mm diam on PDA after 1 mo at 25 °C in the dark; colonies fertile.

Specimen examined: Korea, Pyongchang, Hosta plantaginea (Hostaceae), 20 Sep. 2003, H.D. Shin, HAL 2030 F, holotype, culture ex-type SMK 19664, CPC 10737 = CBS 121637, CPC 10738-10739.

Notes: Although this species is morphologically similar to Cladophialophora scillae (Deighton) Crous, U. Braun & K. Schub. described below in this paper, C. hostae is treated as a separate taxon due to the differences in the length and width of its conidiophores and conidia in vitro, as well as 17 bp differences in the ITS DNA sequence data and a distinct ecology causing leaf-spots on a different, unrelated host. Based on disease symptoms caused on the living host leaves, C. hostae is a very unusual, unexpected member of the genus Cladophialophora. In vivo, the mycelium forms obvious hyphal strands and plates which are characteristic for Fusicladium species. The conidiophores and conidia are also fusicladium-like. Nevertheless, this species clusters within the Herpotrichiellaceae, i.e., it has to be placed in the genus Cladophialophora. Biotrophic species like C. hostae and C. scillae without phialidic synanamorphs render the differentiation between Cladophialophora and Fusicladium (incl. Pseudocladosporium) almost impossible without sequence data. Furthermore, the morphology of C. hostae in vivo and in vitro shows remarkable differences in conidiophore morphology, i.e., the growth in vivo is characteristically fusicladium-like (conidiophores macronematous, long, septate), whereas habit in vitro is rather pseudocladosporium-like (conidiophores less developed, usually reduced to conidiogenous cells, short). However, several Fusicladium species have also been observed to exibit a Pseudocladosporium growth habit in culture, suggesting this growth plasticity to be rather common, and strongly influenced by growth conditions.

Cladophialophora humicola Crous & U. Braun, sp. nov. MycoBank MB504528. Figs ​Figs77-​-88.

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Fig. 7.

Cladophialophora humicola (CBS 117536). Conidiophore with branched conidial chains. Scale bar = 10 μm.

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Fig. 8.

Cladophialophora humicola (CBS 117536). A. Hyphal coil. B. Conidiophore. C-F. Conidial chains with ramoconidia and conidia. Scale bar = 10 μm.

Etymology: Named after its ecology, namely occurring in soil.

Cladophialophorae bantianae similis, sed conidiis majoribus, (8-)11-14(-17) × (1.5-)2(-2.5) μm, locis conidiogenis et hilis angustioribus, 1-1.5 μm latis.

In vitro: Mycelium composed of branched, smooth, pale olivaceous to pale brown hyphae, frequently forming hyphal coils, prominently guttulate, not to slightly constricted at the septa, 1-2 μm wide, cells somewhat uneven in width. Conidiophores solitary, mostly inconspicuous and integrated in hyphae, varying from inconspicuously truncate lateral loci on hyphal cells, 1-1.5 μm wide, to occasionally terminal conidiophores, 0-3-septate, subcylindrical, proliferating sympodially, 10-30 × 1.5-3 μm, pale brown, smooth.

Conidiogenous cells integrated, inconspicuous, truncate, lateral loci 1-1.5 μm wide, or conidiogenous cells subcylindrical with 1-3 sympodial loci (which appear as minute lateral denticles), 7-17 × 1.5-2 μm; scars inconspicuous, neither darkened, refractive nor thickened. Conidia in short chains of up to 10, simple or branched, subcylindrical to narrowly ellipsoid, 0-1-septate, (8-)11-14(-17) × (1.5-)2(-2.5) μm, pale olivaceous to olivaceous-brown or pale brown, smooth, hila truncate, 1-1.5 μm wide, unthickened, neither darkened, nor refractive.

Cultural characteristics: Colonies erumpent, spreading, with uneven, feathery margins and dense aerial mycelium on PDA; pale olivaceous-grey in the middle, becoming olivaceous-grey in the outer zone (surface); reverse olivaceous-black, with grey-olivaceous margins. Colonies reaching 7 mm diam after 2 wk at 25 °C in the dark; colonies fertile.

Specimen examined: Germany, Brandenburg, Müncheberg, from soil, Zaspel, Zalf & H. Nirenberg, holotype CBS H-19902, culture ex-type BBA 65570 = CBS 117536.

Notes: Phylogenetically Cladophialophora humicola is closely related to C. sylvestris Crous & de Hoog (see below). Morphologically the two species can be distinguished in that C. humicola lacks ramoconidia, and has 1-septate conidia, while those of C. sylvestris are 0-3-septate.

Cladophialophora potulentorum Crous & A.D. Hocking, sp. nov. MycoBank MB504529. Figs ​Figs99-​-1010.

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Fig. 9.

Cladophialophora potulentorum (CBS 115144). A. Colony on PDA. B. Conidiophore. C-D. Conidial chains. E-F. Ramoconidia and conidia. Scale bar = 10 μm.

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Fig. 10.

Cladophialophora potulentorum (CBS 115144). Conidiophores with chains of ramoconidia and conidia. Scale bar = 10 μm.

Etymology: Refers to its presence in fruit juices and sports drinks.

Cladophialophorae carrionii similis, sed conidiis secundis majoribus, (6-)8-10(-13) × 2-3 μm.

In vitro: Mycelium consisting of branched, septate, smooth, pale brown, guttulate, 1.5-2.5 μm wide hyphae. Conidiophores solitary, macronematous, well distinguishable under the dissecting microscope from aerial mycelium, pale to medium brown, subcylindrical, straight to somewhat curved, erect, with apical apparatus appearing as a tuft due to extremely long conidial chains; conidiophores up to 5-septate, and 100 μm tall (excluding conidiogenous cells). Conidiogenous cells pale brown, smooth, terminal and lateral, subcylindrical, tapering towards subtruncate to truncate loci, 1 μm wide, somewhat darkened, thickened, but not refractive, loci appearing subdenticulate on lateral conidiogenous cells, mono- to polyblastic, proliferating sympodially, 10-35 × 1.5-2 μm. Conidia pale brown, smooth, guttulate, occurring in branched chains of up to 60; hila somewhat darkened and thickened, but not refractive, 0.5 μm wide; ramoconidia subcylindrical, 0-1-septate, 15-17(-20) × 2.5-3 μm; conidia ellipsoid, (6-)8-10(-13) × 2-3 μm.

Cultural characteristics: Colonies erumpent, spreading, with smooth margins and dense aerial mycelium on PDA, olivaceous-grey (surface), with a thin, olivaceous-black margin; reverse olivaceous-black; on OA olivaceous-grey (surface) with a wide olivaceous-black margin. Colonies reaching 25-30 mm diam after 1 mo at 25 °C in the dark; colonies fertile, also sporulating in the agar. Not able to grow at 37 °C.

Specimens examined: Australia, isolated from apple juice drink, Dec. 1986, A.D. Hocking, holotype CBS H-19901, culture ex-type CBS 115144 = CPC 11048; Australia, isolated from sports drink, Feb. 1996, A.D. Hocking, CBS 114772 = CPC 1375 = FRR 4947; Australia, isolated from sports drink, Feb. 1996, A.D. Hocking, CBS 112222 = FRR 4946.

Notes: Originally this taxon, isolated from fruit and sports drinks, was thought to be an undescribed species of Pseudocladosporium (= Fusicladium, see below). However, upon closer examination, this proved not to be the case. Conidiophores appear as distinct tufts under the dissecting microscope, and are readily distinguishable from the superficial mycelium, as is normally observed in species of Fusicladium, but the conidial chains are extremely long, and the conidia tend to be more ellipsoid than the predominantly fusiform or subcylindrical conidia observed in species of Fusicladium. Hyphal coils were also not observed in cultures of C. potulentorum, but are rather common in species of Fusicladium. The phylogenetic position of this taxon within the Herpotrichiellaceae clade also supports inclusion in the genus Cladophialophora.

Cladophialophora proteae Viljoen & Crous, S. African J. Bot. 64: 137. 1998. Fig. 11.

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Fig. 11.

Cladophialophora proteae (CBS 111667). A. Colony on OA. B-C. Conidiophores. D-H. Catenulate conidia. Scale bars = 10 μm.

• ≡ Pseudocladosporium proteae (Viljoen & Crous) Crous, in Crous et al., Cultivation and Diseases of Proteaceae: Leucadendron, Leucospermum and Protea: 101. 2004.

In vitro: Mycelium consisting of branched, septate hyphae, often forming strands, anastomosing, smooth to finely verruculose, frequently constricted at septa, olivaceous, 3-4 μm wide; hyphal cells in older cultures becoming swollen, up to 6 μm wide. Conidiophores reduced to conidiogenous cells. Conidiogenous cells holoblastic, integrated, forming short, truncate protuberances, 2-3 × 1.5-2 μm, concolorous with mycelium, subcylindrical. Conidia in vitro arranged in long acropetal chains (up to 20), simple or branched, subcylindrical to oblong-doliiform, (9-)13-17(-22) × 2.5-3(-4) μm in vitro on MEA, (9-)16-22(-25) × (2.5-)3-4(-6) μm on SNA; 0-1(-4)-septate, pale brown to pale olivaceous, smooth, hila subtruncate to truncate, not thickened, but somewhat refractive.

Cultural characteristics: Colonies erumpent, with sparse aerial mycelium on PDA; margins irregular, feathery; greyish rose, with patches of pale olivaceous-grey (surface); reverse olivaceous-grey. Colonies reaching 10 mm diam after 2 wk at 25 °C in the dark; colonies fertile.

Specimen examined: South Africa, Western Cape Province, Stellenbosch, J.S. Marais Nature Reserve, leaves of Protea cynaroides (Proteaceae), 26 Aug. 1996, L. Viljoen, holotype PREM 55345, culture ex-type CBS 111667.

Notes: Cladophialophora proteae differs from species of Fusicladium (= Pseudocladosporium) based on its colony colour, the slimy nature of colonies, as well as its conidia that have inconspicuous, unthickened hila (Fig. 11) (Crous et al. 2004), unlike those observed in species of Fusicladium. Sequence data show that this species is not allied to the Venturiaceae, but to the Herpotrichiellaceae.

Cladophialophora scillae (Deighton) Crous, U. Braun & K. Schub., comb. nov. MycoBank MB504530. Fig. 12.

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Fig. 12.

Cladophialophora scillae (CBS 116461). A-C. Conidiophores. D-F. Catenulate conidia. Scale bar = 10 μm.

Basionym: Cladosporium scillae Deighton, N. Zealand J. Bot. 8: 55. 1970.

• ≡ Fusicladium scillae (Deighton) U. Braun & K. Schub., IMI Descriptions of Fungi and Bacteria 152: 1518. 2002.

In vivo: see Schubert & Braun (2002a) and Schubert et al. (2003).

In vitro: Mycelium consisting of branched, septate, smooth, green-brown to medium brown, guttulate hyphae, variable in width, 1.5-3 μm diam. Conidiophores lateral or terminal on hyphae, erect, straight to slightly flexuous, solitary, in some cases aggregated, subcylindrical, curved to geniculate-sinuous, unbranched, up to 55 μm long, 2-3 μm wide, 0-7-septate, septa in short succession, pale to medium brown, somewhat paler towards apices, smooth. Conidiogenous cells integrated, terminal or lateral as individual loci on hyphal cells, straight to curved, subcylindrical, up to 14(-18) μm long and 2 μm wide, pale to medium brown, smooth, with a single or few subdenticulate to denticulate loci at the apex due to sympodial proliferation, or reduced to individual loci, 0.8-1.5(-2) μm wide; scars minutely thickened and darkened, but not refractive. Conidia occurring in long, unbranched or loosely branched chains (-30), straight to slightly curved, ellipsoid to mostly narrowly subcylindrical, obclavate in some larger, septate conidia, (5-)10-20(-35) × 1.5-3 μm, 0-1(-3)-septate, sometimes slightly constricted at the septa, subhyaline to pale brown, smooth, guttulate, tapering at ends to subtruncate hila, 0.8-1.5 μm wide, minutely thickened and darkened, but not refractive; microcyclic conidiogenesis occurring.

Cultural characteristics: Colonies erumpent, spreading, with smooth, even margins and dense, abundant aerial mycelium on PDA; grey-olivaceous (surface); reverse dark olivaceous. Colonies on OA olivaceous-grey, smoke-grey due to profuse sporulation, reverse olivaceous-grey to iron-grey, velvety, aerial mycelium sparse, diffuse. Colonies reaching 20 mm diam on SNA, and 40 mm on PDA after 1 mo at 25 °C in the dark; colonies fertile.

Specimens examined: New Zealand, Levin, on Scilla peruviana (Hyacinthaceae), 21 Dec. 1965, G.F. Laudon, IMI 116997 holotype; Auckland, Manurewa, Auckland Botanic Gardens, on leaf spots of Scilla peruviana, 25 Apr. 2004, C.F. Hill, 1044, CBS H-19903, epitype designated here, culture ex-type CBS 116461.

Notes: In culture Cladophialophora scillae forms a pseudocladosporium-like state, though the scars are somewhat darkened and thickened, but not refractive. Conidiophores are reduced to conidiogenous cells that are integrated in the mycelium, terminal or lateral, frequently also as an inconspicuous lateral denticle, with a flat-tipped scar. Conidia occur in long, branched chains, which are subcylindrical to narrowly ellipsoid, and are up to 35 μm long, 1.5-3 μm wide, thus longer and thinner than reported on the host, which were 0-3-septate, subcylindrical to ellipsoid-ovoid, 7-22 × 2.5-4 μm. Due to the fusicladioid habit of this species in vivo, Schubert & Braun (2002a) reallocated it to Fusicladium. Based on ITS sequence data, morphology and cultural characteristics, Cladophialophora scillae was almost identical to an isolate obtained from leaf spots of Hosta plantaginea in Korea. These isolates appeared to resemble species of Fusicladium, but phylogenetically they clustered in the Herpotrichiellaceae. Therefore, “Fusicladium” scillae was placed in the genus Cladophialophora. As far as we are aware, this species and C. hostae are first reports of phytopathogenic species within the genus Cladophialophora.

Cladophialophora sylvestris Crous & de Hoog, sp. nov. MycoBank MB504531. Fig. 13.

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Fig. 13.

Cladophialophora sylvestris (CBS 350.83). A-B. Conidiophores. C. Catenulate conidia. D. Conidial mass. Scale bar = 10 μm.

Etymology: Refers to its host, Pinus sylvestris.

Cladophialophorae humicolae similis, sed conidiis 0-3-septatis, (7-)10-16(-20) × 1.5-2 μm.

Mycelium composed of branched, smooth, pale olivaceous to pale brown hyphae, frequently forming hyphal coils, not to slightly constricted at the septa, 1-2 μm wide. Conidiophores medium brown, subcylindrical, flexuous, mononematous, multiseptate, up to 50 μm long, and 2-3 μm wide. Conidiogenous cells apical, sympodial, pale brown, 5-12 × 2-3 μm; scars somewhat darkened and thickened, not refractive. Conidia occurring in branched chains; ramoconidia up to 2 μm wide, giving rise apically to disarticulating chains of conidia; smooth, 0-3-septate, pale olivaceous, subcylindrical, (7-)10-16(-20) × 1.5-2 μm, with truncate ends; hila somewhat darkened and thickened, not refractive.

Cultural characteristics: Colonies erumpent on PDA, with smooth, catenulate margins; iron-grey (surface); reverse greenish black. Colonies reaching 15 mm diam after 1 mo at 25 °C in the dark; colonies fertile.

Specimen examined: Netherlands, Kootwijk, needle litter of Pinus sylvestris (Pinaceae), 8 Nov. 1982, G.S. de Hoog, holotype CBS H-19917, culture ex-type CBS 350.83.

Notes: Morphologically CBS 350.83 was originally identified as Polyscytalum griseum Sacc., but the latter is reported to have conidia that are 5-5.5 × 1 μm (Saccardo 1877), which is much smaller than that observed for the present isolate. Furthermore, the type species of Polyscytalum, P. fecundissimum Riess (CBS 100506), does not cluster within the Herpotrichiellaceae, thus suggesting that CBS 350.83 is best treated as a new species of Cladophialophora.

Cyphellophora hylomeconis Crous, de Hoog & H.D. Shin, sp. nov. MycoBank MB504532. Fig. 14.

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Fig. 14.

Cyphellophora hylomeconis (CBS 113311). A. Colony on PDA. B-C. Hyphae with truncate conidiogenous loci. D-F. Conidia. Scale bars = 10 μm.

Etymology: Named after its host genus, Hylomecon.

Cyphellophorae lacinatae similis, sed conidiis longioribus et leniter angustioribus, (15-)25-35(-55) × (2.5-)3(-4) μm.

Mycelium consisting of branched, greenish brown, septate, branched, smooth, 3-5 μm wide hyphae, constricted at septa. Conidiogenous cells phialidic, intercalary, appearing denticulate, 1 μm tall, 1.5-2 μm wide, with minute collarettes (at times proliferating percurrently). Conidia sickle-shaped, smooth, medium brown, guttulate, (1-)3(-5)-septate, constricted at septa, widest in middle, or lower third of the conidium; apex subacutely rounded, base subtruncate, or having a slight constriction, giving rise to a foot cell, 1 μm long, 0.5-1 μm wide, subacutely rounded, (15-)25-35(-55) × (2.5-)3(-4) μm; a marginal frill is visible above the foot cell, suggesting this foot cell may be the onset of basal germination; conidia also anastomose and undergo microcyclic conidiation in culture.

Cultural characteristics: Colonies slow-growing, slimy, aerial mycelium absent, margins smooth, catenate; surface crumpled, olivaceous-black to iron-grey. Colonies reaching 20 mm diam after 1 mo at 25 °C in the dark on PDA, 12 mm on SNA; colonies fertile.

Specimen examined: Korea, Yangpyeong, on leaves of Hylomecon verlance (Papaveraceae), 4 Jun. 2003, H.D. Shin, holotype CBS H-19907, isotype SMK 19550, culture ex-type CBS 113311.

Notes: Cyphellophora hylomeconis is related to the type species of the genus, Cyphellophora laciniata G.A. de Vries, which also resides in the Herpotrichiellaceae. The genus Cyphellophora G.A. de Vries is phenetically distinguished from Pseudomicrodochium B.C. Sutton, typified by P. aciculare B.C. Sutton (1975) by melanized versus hyaline thalli. Phylogenetic confirmation is pending due to unavailability of sequence data. Decock et al. (2003) synonymised the hyaline genus Kumbhamaya M. Jacob & D.J. Bhat (Jacob & Bhat 2000) with Cyphellophora, but as no cultures of this fungus are available this decision seems premature. Nearly all Cyphellophora species accepted by Decock et al. (2003) have been found to be involved in cutaneous infections in humans. This also holds true for the species originally described as being environmental, C. vermispora Walz & de Hoog, which is closely related to C. suttonii (Ajello et al.) Decock and C. fusarioides (C.K. Campbell & B.C. Sutton) Decock known from proven human and animal infections. Decock et al. (2003) added the melanized species C. guyanensis Decock & Delgado, isolated as a saprobe from tropical leaf litter. Cyphellophora hylomeconis is the first species of the genus infecting a living plant host. ITS sequences are remote from those of the remaining Cyphellophora species, the nearest neighbour being C. pluriseptata G.A. de Vries, Elders & Luykx at 19.1 % distance (data not shown). Cyphellophora hylomeconis can be distinguished based on its conidial dimensions and septation. Conidia are larger than those of C. fusarioides (11-20 × 2-2.5 μm, 1-2-septate), and those of C. laciniata (11-25 × 2-5 μm, 1-3-septate) (for a key to the species see Decock et al. 2003).

Exophiala sp. 1. Fig. 15.

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Fig. 15.

Exophiala sp. 1 (CBS 115142). A. Colony on PDA. B. Hyphal coil. C. Hyphal strand. D-H. Conidiogenous cells and loci. I-O. Conidiogenous cells and conidia. Scale bars = 10 μm.

Mycelium consisting of smooth, branched, septate, medium brown, 2-3 μm wide hyphae, regular in width, forming hyphal strands and hyphal coils, with free yeast-like cells present in culture; chlamydospores terminal on hyphae, frequently forming clusters or chains, medium brown, ellipsoid, 0-1-septate, up to 10 μm long and 5 μm wide. Conidiophores reduced to conidiogenous cells, or consisting of one supporting cell, giving rise to a single conidiogenous cell, subcylindrical to ellipsoid, medium brown, smooth, 5-12 × 3.5-4 μm, with 1(-3) phialidic loci, somewhat protruding, appearing subdenticulate at first glance under the light microscope. Conidiogenous cells integrated as lateral loci on hyphal cells, inconspicuous, 1-1.5 μm wide, with a slightly flaring collarette, (1-)1.5(-2) μm long. Conidia ellipsoid, smooth, guttulate, becoming brown, swollen and elongated, and at times 1-septate, 4-5(-7) × (2.5-)3(-4) μm (description based on CBS 115142).

Cultural characteristics: Colonies erumpent, spreading, with sparse to dense aerial mycelium on PDA, olivaceous-grey (surface), with a thin to wide, smooth, olivaceous-black margins; reverse olivaceous-black; on OA olivaceous-grey (surface) with wide, olivaceous-black margins. Colonies reaching 40-50 mm diam after 1 mo at 25 °C in the dark; colonies fertile, but sporulation sparse. Not able to grow at 37 °C.

Specimen examined: Australia, from a fruit drink, May 2002, N.J. Charley, CBS 115142 = CPC 11044 = FRR 5582.

Notes: Species of Exophiala are frequently observed as agents of human mycoses in immunocompromised patients (de Hoog et al. 2000). They are found in the environment as slow-growing, oligotrophic colonisers of moist substrates. For example the thermotolerant species E. dermatitidis (Kano) de Hoog and E. phaeomuriformis (Matsumoto et al.) Matos et al. are common in public steam baths (Matos et al. 2003), while E. mesophila Listemann & Freiesleben can be found in showers and swimming pools (unpubl. data). Both species are able to cause infections in humans (Zeng et al. 2007). Several other species have been associated primarily with infections in fish and cold-blooded animals (Richards et al. 1978) and are occasionally found on humans (Madan et al. 2006). The occurrence of the present species in fruit drinks, therefore, is cause of concern, although it was unable to grow at 37 °C. This species forms part of a larger study, and will be treated elsewhere.

Exophiala sp. 2. Fig. 16.

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Fig. 16.

Exophiala sp. 2 (CBS 115143). A. Conidiogenous cells. B. Conidiophore with hyphal coil. C. Conidiogenous cell with hyphal strand. D. Conidia. Scale bar = 10 μm.

Mycelium consisting of smooth, branched, septate, pale brown, 1.5-3 μm wide hyphae, forming hyphal strands and hyphal coils; hyphae at times terminating in chains of ellipsoid chlamydospores that are medium brown, smooth, up to 10 μm long and 5 μm wide. Conidiophores subcylindrical, medium brown, smooth, consisting of a supporting cell and a single conidiogenous cell, or reduced to a conidiogenous cell, straight to curved, up to 30 μm long and 2-3 μm wide. Conidiogenous cells pale to medium brown, subcylindrical to narrowly ellipsoid or subclavate, with 1-3 apical, phialidic loci, 1 μm wide, 1-2 μm tall, collarette somewhat flaring, but mostly cylindrical, 7-20 × 2-2.5 μm; at times proliferating percurrently. Conidia ellipsoid, smooth, guttulate, hyaline, becoming pale olivaceous, apex obtuse, base subtruncate, (4-)5-7(-10) × 2-2.5(-3) μm.

Cultural characteristics: Colonies spreading with smooth, submerged margins, moderate aerial mycelium on PDA, sparse on OA, on PDA and OA olivaceous-grey (surface), with a wide, iron-grey margin; reverse iron-grey. Colonies reaching 40-50 mm diam after 1 mo at 25 °C in the dark; colonies fertile. Not able to grow at 37 °C.

Specimen examined: Australia, from bottled spring water, May 2003, N.J. Charley, CBS 115143 = CPC 11047 = FRR 5599.

Notes: This strain represents another taxon occurring in bottled drinks destined for human consumption. As it is unable to grow at 37 °C, it does not appear to pose any serious threat to human health. This species forms part of a larger study, and will be treated elsewhere.

Exophiala eucalyptorum Crous, sp. nov. MycoBank MB504533. Fig. 17.

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Fig. 17.

Exophiala eucalyptorum (CPC 11261). A. Colony on PDA. B-H. Hyphae, conidiogenous cells and conidia. Scale bars = 10 μm.

Etymology: Named after its occurrence on Eucalyptus leaves.

Exophialae spiniferae similis, sed conidiis fusoidibus-ellipsoideis, (5-)6-8(-10) × (3-)4-5(-7) μm, et cellulis conidiogenis saepe catenatis, in catenis brevibus, dividentibus.

Mycelium consisting of smooth to finely verruculose, branched, septate, 2-4 μm wide hyphae, at times giving rise to chains of dark brown, fusoid-ellipsoid chlamydospores, which can still have phialides, suggesting they were conidiogenous cells; hyphae becoming constricted at septa when fertile. Conidiophores reduced to conidiogenous cells. Conidiogenous cells numerous, terminal and lateral, mono- to polyphialidic, 5-15 × 3-5 μm; loci 1-1.5 μm wide and tall, with inconspicuous collarettes, at time proliferating percurrently; conidiogenous cells fusoid-ellipsoid, and frequently breaking off, appearing as short chains of conidia, but distinct in having conidiogenous loci. Conidia fusoid-ellipsoid, apex acutely rounded, base subtruncate, (5-)6-8(-10) × (3-)4-5(-7) μm; frequently becoming fertile, septate and brown with age.

Cultural characteristics: Colonies erumpent, convex, smooth, slimy, margins feathery to crenate and smooth; aerial mycelium absent, growth yeast-like. Colonies on PDA, OA and SNA chestnut on surface and reverse. Colonies reaching 4 mm diam after 2 wk on PDA at 25 °C in the dark.

Specimen examined: New Zealand, Wellington Botanical Garden, on leaf litter of Eucalyptus sp. (Myrtaceae), Mar. 2004, J.A. Stalpers, holotype CBS H-19905, culture ex-type CBS 121638 = CPC 11261.

Notes: Exophiala eucalyptorum is rather characteristic in that, in culture, chains of conidiogenous cells frequently detach from hyphae, appearing as short, intact chains of fertile conidia. Its phylogenetic position is somewhat outside the core of the Herpotrichiellaceae containing most Capronia teleomorphs and the remaining opportunistic Exophiala species, but still within the Chaetothyriales (Figs ​(Figs11-​-22).

Venturia Sacc. and its anamorph Fusicladium

Venturia Sacc., Syll. fung. (Abellini) 1: 586. 1882.

• = Apiosporina Höhn., Sitzungsber. Kaiserl. Akad. Wiss., Math.-Naturw. Cl., Abt. 1, 119: 439. 1910, syn. nov.

• = Metacoleroa Petr., Ann. Mycol. 25: 332. 1927, syn. nov.

• = Caproventuria U. Braun, A Monograph of Cercosporella, Ramularia and Allied Genera (Phytopathogenic Hyphomycetes) 2: 396. 1998, syn. nov.

For additional synonyms see Sivanesan, The bitunicate Ascomycetes and their anamorphs: 604. 1984.

Anamorph: Fusicladium Bonord., Handb. Mykol.: 80. 1851.

• = Pseudocladosporium U. Braun, A Monograph of Cercosporella, Ramularia and Allied Genera (Phytopathogenic Hyphomycetes) 2: 392. 1998, syn. nov.

For additional synonyms, see Schubert et al. (2003).

Notes: The genus Caproventuria, based on C. hanliniana (U. Braun & Feiler) U. Braun, was erected to accommodate saprobic, soil-borne venturia-like ascomycetes with numerous ascomatal setae, and an anamorph quite distinct from Fusicladium (Braun 1998). The genus Metacoleroa is based on M. dickiei (Berk. & Broome) Petr., which clusters in the Venturiaceae, adjacent to Caproventuria, which has Pseudocladosporium anamorphs. Metacoleroa was retained by Barr (1987) as separate from Venturia based on its superficial ascomata with a thin, stromatic layer beneath the ascomata. Whether these criteria still justify the separation of Caproventuria and Metacoleroa from Venturia is debatable, and the names Venturia dickiei (Berk. & Broome) Ces. & de Not. and Venturia hanliniana (U. Braun & Feiler) Unter. are available for these organisms. The genus Apiosporina, which is based on Apiosporina collinsii (Schwein.) Höhn., clusters in the Venturiaceae, as was to be expected based on its Fusicladium anamorph (Schubert et al. 2003). It was distinguished from Venturia species by having ascospores strictly septate near the lower end (Sivanesan 1984).

The anamorph genus Fusicladium has been monographed by Schubert et al. (2003). Morphological as well as molecular studies (Beck et al. 2005) demonstrated that the genus Venturia with its Fusicladium anamorphs is monophyletic. A separation of Venturia into various uniform subclades based on the previous anamorph genera Fusicladium, Pollaccia and Spilocaea was not evident and could be rejected. As in cercosporoid anamorphs of Mycosphaerella, features such as the arrangement of the conidiophores (solitary, fasciculate, sporodochial), the proliferation of conidiogenous cells (sympodial, percurrent) and shape, size as well as formation of conidia (solitary, catenate) proved to be of little taxonomic value at generic level. Hence, Schubert et al. (2003) proposed to maintain Fusicladium emend. as sole anamorph genus for Venturia. The genus Fusicladosporium Partridge & Morgan-Jones (type species: Cladosporium carpophilum Thüm.) (Partridge & Morgan-Jones 2003), recently erected to accommodate fusicladium-like species with catenate conidia, represents a further synonym of Fusicladium.

Similar to their occurrence in vivo the conidiophores in vitro of species previously referred to the genera Spilocaea and Pollaccia are usually micronematous, conidia often appear to be directly formed on the mycelium, unilocal, determinate, mostly reduced to conidiogenous cells, sometimes forming a few percurrent proliferations, whereas the conidiophores of species of Fusicladium s. str. are mostly macronematous, but sometimes also micronematous. They are often initiated as short lateral, peg-like outgrowths of hyphae which proliferate sympodially, becoming slightly geniculate, forming a single, several or numerous subdenticulate to denticulate, truncate, unthickened or only slightly thickened, somewhat darkened-refractive conidiogenous loci.

The genus Pseudocladosporium was described to be quite distinct from Fusicladium by being saprobic and connected with a different teleomorph, viz. Caproventuria (Braun 1998). However, since the type species of Caproventuria, C. hanliniana, with its anamorph Pseudocladosporium brevicatenatum (U. Braun & Feiler) U. Braun clusters together with numerous Venturia species, the genus Pseudocladosporium should be reduced to synonymy with Fusicladium. Morphologically there is no clear delimitation between Fusicladium and Pseudocladosporium. The typically pseudocladosporium-like habit, characterised by forming solitary conidiophores, often reduced to conidiogenous cells or even micronematous, and conidia formed in long chains, is mainly found in culture, above all in saprobic taxa. The fusicladium-like growth with well-developed macronematous conidiophores is usually more evident in vivo, above all in biotrophic taxa. There are, however, all kinds of transitions between these two genera.

Fusicladium africanum Crous, sp. nov. MycoBank MB504535. Fig. 19.

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Fig. 19.

Fusicladium africanum (CPC 12828). A. Colony on MEA. B. Hyphal coil. C. Branched conidial chain. D-F. Conidiophores with catenulate conidia. Scale bar = 10 μm.

Etymology: Named after the continent from which it was collected, Africa.

Fusicladio brevicatenato similis, sed conidiophoris brevioribus, 5-10 μm longis, conidiis minoribus, ad 20 × 3.5 μm, 0(-1)-septatis, locis conidiogenis et hilis angustioribus, 1-1.5 μm latis.

Mycelium composed of smooth, medium brown, branched, septate, 1.5-2 μm wide hyphae, frequently forming hyphal coils. Conidiophores reduced to conidiogenous cells, solitary, pale to medium brown, smooth, inconspicuous, integrated in hyphae, varying from small, truncate lateral loci on hyphal cells, 1-1.5 μm wide, to micronematous conidiogenous cells, 5-10 × 2-3 μm; mono- to polyblastic, sympodial, scars inconspicuous, 1 μm wide. Conidia in long, branched chains of up to 40, subcylindrical, 0(-1)-septate, pale brown, smooth; hila truncate, 1 μm wide, unthickened, neither darkened nor refractive; ramoconidia (11-)15-17(-20) × 2-3(-3.5) μm; conidia (8-)11-17 × 2-2.5 μm.

Cultural characteristics: Colonies somewhat erumpent, with moderate aerial mycelium and smooth, lobate margins on PDA, ochreous to umber (surface); reverse dark umber; on OA umber; on SNA ochreous. Colonies reaching 9 mm diam on PDA after 2 wk at 25 °C in the dark; colonies fertile.

Specimen examined: South Africa, Western Cape Province, Malmesbury, Eucalyptus leaf litter, Jan. 2006, P.W. Crous, holotype CBS H-19904, cultures ex-type CPC 12828 = CBS 121639, CPC 12829 = CBS 121640.

Notes: Fusicladium africanum is a somewhat atypical member of the genus, as its conidial hila are quite unthickened and inconspicuous. Among biotrophic, leaf-spotting Fusicladium species a wider morphological variation was found pertaining to the structure of the conidiogenous loci and conidial hila, ranging from being indistinct, unthickened and not darkened-refractive to unthickened or almost so, but somewhat darkened-refractive (Schubert et al. 2003). Fusicladium africanum was found occurring with Sympoventuria capensis Crous & Seifert on Eucalyptus leaf litter in South Africa (Crous et al. 2007b).

Fusicladium amoenum (R.F. Castañeda & Dugan) Crous, K. Schub. & U. Braun, comb. nov. MycoBank MB504536. Fig. 20.

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Fig. 20.

Fusicladium amoenum (CBS 254.95). A-E. Conidiophores with conidiogenous loci. F. Conidia. Scale bar = 10 μm.

Basionym: Anungitopsis amoena R.F. Castañeda & Dugan, Mycotaxon 72: 118. 1999.

• ≡ Cladosporium amoenum R.F. Castañeda, in Untereiner et al., 1998, nom. nud.

Specimen examined: Cuba, Santiago de Cuba, La Gran Piedra, fallen leaves of Eucalyptus sp. (Myrtaceae), 2 Nov. 1994, R.F. Castañeda, (Ho et al. 1999: 117, figs ​figs22-​-3) 3) iconotype, culture ex-type CBS 254.95 = ATCC 200947 = IMI 367525 = INIFAT C94/155 = MUCL 39143.

Note: In culture F. amoenum has a typical pseudocladosporium-like morphology, though the scars are neither prominently thickened, nor refractive.

Fusicladium caruanianum Sacc., Ann. Mycol. 11: 20. 1913.

• ≡ Pseudocladosporium caruanianum (Sacc.) U. Braun, Schlechtendalia 9: 114. 2003.

Fusicladium convolvularum Ondřej, Česká Mycol. 25: 171. 1971. Fig. 21.

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Fig. 21.

Fusicladium convolvularum (CBS 112706). A-B, D-I. Conidiophores with conidiogenous loci. C, J-K. Ramoconidia and conidia. Scale bars = 10 μm.

In vivo: Schubert et al. (2003: 37).

In vitro on SNA: Mycelium unbranched or only sparingly branched, 2-3 μm wide, septate, not constricted at septa, subhyaline to pale brown, smooth, walls unthickened or almost so. Conidiophores laterally arising from hyphae, erect, straight to somewhat flexuous, sometimes geniculate, unbranched, (6-)12-75 × (2.5-)3-4.5 μm, aseptate or septate, pale brown or pale medium brown, smooth, walls somewhat thickened, sometimes only as short lateral conical prolongations of hyphae, occasionally irregular in shape. Conidiogenous cells integrated, terminal or conidiophores reduced to conidiogenous cells, sometimes geniculate, 6-29 μm long, proliferation sympodial, with several denticle-like loci, broadly truncate, 1.5-2(-2.5) μm wide, unthickened, somewhat refractive or darkened. Ramoconidia occurring, 20-28 × 5 μm, 0-1-septate, somewhat darker, pale medium brown, with a broadly truncate base, 3-4 μm wide, usually with several denticle-like apical loci. Conidia catenate, formed in unbranched or loosely branched chains, straight to sometimes curved, cells sometimes irregularly swollen, fusiform, subcylindrical, sometimes obpyriform, 13-35 × 3.5-5.5(-6) μm, 0-3-septate, occasionally slightly constricted at the median septum, few very large conidia with up to five septa, up to 75 μm long, 4.5-6 μm wide, subhyaline to pale brown, smooth, walls slightly thickened, slightly attenuated towards apex and base, hila broadly truncate, 1-2 μm wide, unthickened or only slightly thickened, somewhat darkened-refractive; microcyclic conidiogenesis occurring, conidia often germinating.

Cultural characteristics: Colonies on PDA spreading, somewhat erumpent, with moderate aerial mycelium and regular, but feathery margins; surface fuscous black, and reverse dark fuscous black. Colonies reaching 15 mm diam after 1 mo on PDA at 25 °C in the dark.

Specimens examined: Czech Republic, Libina, okraj pole pod nadrazim (okr. Sumperk), on Convolvulus arvensis (Convolvulaceae), 7 Sep. 1970, Ondřej, holotype BRA. new Zealand, on leaves of Convolvulus arvensis, 7 Nov. 2000, C.F. Hill, epitype designated here CBS H-19911, culture ex-epitype CBS 112706 = CPC 3884 = IMI 383037.

Note: Conidiophores are somewhat longer and narrower in vitro than in vivo, and ramoconidia occur (Schubert & Braun 2002b, Schubert et al. 2003).

Fusicladium fagi Crous & de Hoog, sp. nov. MycoBank MB504537. Fig. 22.

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Fig. 22.

Fusicladium fagi (CBS 621.84). A. Conidiophore with truncate conidiogenous loci. B. Hypha with conidiogenous loci. C-G. Conidial chains. Scale bars = 10 μm.

Etymology: Named after its host, Fagus sylvatica.

Fusicladio brevicatenato similis, sed conidiis secundis minoribus, (8-)11-17(-20) × 3-3.5 μm, locis conidiogenis et hilis angustioribus, 1-1.5 μm latis.

Mycelium consisting of pale to medium brown, smooth to finely verruculose, branched, 2-3 μm wide hyphae. Conidiophores integrated, terminal on hyphae, 0-1-septate, mostly reduced to conidiogenous cells, also lateral, visible as small, protruding, denticle-like loci, 10-15 × 2-3.5 μm. Conidiogenous cells subcylindrical, 5-15 × 2-3.5 μm, pale to medium brown, smooth to finely verruculose, tapering to 1-3 apical loci, 1-1.5 μm wide; scars inconspicuous. Conidia pale brown, smooth, guttulate, subcylindrical to narrowly ellipsoid, occurring in simple or branched chains, 0-1(-2)-septate, tapering towards subtruncate ends, 1.5-2.5 μm wide, aseptate conidia (8-)11-17(-20) × 3-3.5 μm, septate conidia up to 40 μm long and 4 μm wide; hila inconspicuous, i.e. neither thickened nor darkened-refractive; microcyclic conidiation common in older cultures.

Cultural characteristics: Colonies erumpent, spreading, with abundant aerial mycelium on PDA, and feathery to smooth margins; isabelline to patches of fuscous-black due to the absence of aerial mycelium, which collapses with age (surface); reverse fuscous-black. Colonies reaching 50 mm diam after 1 mo at 25 °C in the dark; colonies fertile.

Specimen examined: Netherlands, Baarn, Maarschalksbosch, decaying leaves of Fagus sylvatica (Fagaceae), 1 Oct. 1984, G.S. de Hoog, holotype CBS H-10366, culture ex-type CBS 621.84 = ATCC 200937.

Notes: Isolate CBS 621.84 was until recently preserved at the CBS as representative of Cladosporium nigrellum Ellis & Everh., a species known from bark of Robinia sp. in the U.S.A. Morphologically it is, however, quite distinct in having somewhat larger, and more subcylindrical to ellipsoid conidia. Conidia of C. nigrellum are fusiform to limoniform, 0-3-septate, 5-15 × 4-7 μm (Ellis 1976), possessing the typical cladosporioid scars with a central convex dome and a periclinal rim which characterise it as a true member of the genus Cladosporium Link, which has been confirmed by a re-examination of type material of C. nigrellum (on inner bark of railroad ties, U.S.A., West Virginia, Fayette Co., Nuttallburg, 20 Oct. 1893, L.A. Nuttall, Flora of Fayette County No. 172, NY; also Ellis & Everh., N. Amer. Fungi 3086 and Fungi Columb. 382, BPI, NY, PH).

Fusicladium intermedium (Crous & W.B. Kendr.) Crous, comb. nov. Mycobank MB504538. Fig. 23.

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Fig. 23.

Fusicladium intermedium (CBS 110746). A-G. Conidiophores with sympodial conidiogenous loci. H. Conidia. Scale bar = 10 μm.

Basionym: Anungitopsis intermedia Crous & W.B. Kendr. S. Afr. J. Bot. 63: 286. 1997.

Specimens examined: South Africa, Mpumalanga, from leaf litter of Eucalyptus sp. (Myrtaceae), Oct. 1992, M.J. Wingfield, PREM 51438 holotype. Madagascar, Tamatave, Eucalyptus leaf litter, Apr. 1994, P.W. Crous, CBS H-19918, epitype designated here, culture ex-epitype CPC 778 = IMI 362702 = CBS 110746.

Note: Conidiophores are dimorphic in culture, being macronematous, anungitopsis-like, and micronematous, more pseudocladosporium-like.

Fusicladium matsushimae (U. Braun & C.F. Hill) Crous, U. Braun & K. Schub., comb. nov. Mycobank MB504539.

Basionym: Pseudocladosporium matsushimae U. Braun & C.F. Hill, Australas. Pl. Pathol. 33: 492. 2004.

Fusicladium mandshuricum (M. Morelet) Ritschel & U. Braun, Schlechtendalia 9: 62. 2003.

Basionym: Pollaccia mandshurica M. Morelet, Ann. Soc. Sci. Nat. Archéol. Toulon Var 45(3): 218. 1993.

• = Pollaccia sinensis W.P. Wu & B. Sutton, in herb. (IMI).

Teleomorph: Venturia mandshurica M. Morelet, Ann. Soc. Sci. Nat. Archéol. Toulon Var 45(3): 219. 1993.

In vivo: Schubert et al. (2003: 62).

In vitro on OA: Mycelium loosely branched, filiform to narrowly cylindrical-oblong, 1-4 μm wide, later somewhat wider, up to 7 μm, septate, sometimes slightly constricted at the septa, sometimes irregular in outline due to small swellings, subhyaline to pale brown, smooth, walls unthickened, sometimes aggregating, forming compact conglomerations of slightly swollen hyphal cells. Conidiophores usually reduced to conidiogenous cells, arising terminally or laterally from hyphae, subcylindrical to cylindrical, unbranched, 9-20 × (2.5-)4-5(-6) μm, aseptate, very rarely 1-septate, very pale brown, smooth, walls unthickened, monoblastic, unilocal, determinate, later occasionally becoming percurrent, enteroblastically proliferating, forming a few (up to five) annellations, loci broadly truncate, (2-)3-5 μm wide, unthickened, not darkened. Conidia solitary, straight to curved, fusiform to obclavate, distinctly apiculate, 24-45(-57) × (6-)7-9(-10.5) μm, (1-)2-4(-5)-septate, more or less constricted at septa, sometimes up to 85 μm long with up to 7 septa, septa often somewhat darkened, second cell often bulging, pale medium to medium olivaceous-brown or brown, smooth, walls somewhat thickened, somewhat attenuated towards the base, hilum broadly truncate, (2-)3-5 μm wide, unthickened, not darkened; microcyclic conidiogenesis not observed.

Cultural characteristics: Colonies on OA iron-grey to olivaceous-grey due to aerial mycelium and sporulation (surface); reverse iron-grey to black, somewhat velvety; margin glabrous, olivaceous; aerial mycelium sparsely formed, loose, diffuse; sporulating.

Specimens examined: China, Liaoning, on Populus simonii × P. nigra, 17 Jun. 1992, M. Morelet, holotype PC (PFN 1466); P. simonii, 20 Apr. 1993, epitype designated here CBS H-19912, culture ex-epitype CBS 112235 = CPC 3639 = MPFN 307.

Note: Conidiophores are densely fasciculate in vivo, forming sporodochial conidiomata, cylindrical to ampulliform, 5-7 × 6-7.5 μm (Schubert et al. 2003).

Fusicladium pini Crous & de Hoog, sp. nov. MycoBank MB504540. Fig. 24.

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Fig. 24.

Fusicladium pini (CBS 463.82). A-F. Conidiogenous cells with conidiogenous loci. G. Conidia. Scale bars = 10 μm.

Etymology: Named after its host, Pinus.

Fusicladio africano similis, sed conidiis minoribus, (6-)10-12(-17) × 1.5-2(-2.5) μm, locis conidiogenis et hilis angustioribus, 0.5-1 μm latis.

Mycelium consisting of smooth, medium brown, branched, 1.5-2 μm wide hyphae, giving rise to solitary, micronematous conidiophores. Conidiophores reduced to conidiogenous cells, medium to dark brown, erect, thick-walled, smooth, subcylindrical, widest at the base, tapering to a subtruncate apex, 5-15 × 2-3 μm; scars flat-tipped, somewhat darkened and thickened, one to several in the apical region, somewhat protruding, 0.5-1 μm wide. Conidia in branched or unbranched chains of up to 15, medium brown, smooth, subcylindrical, 0-1-septate, widest in the middle, tapering to subtruncate ends, straight to slightly curved, (6-)10-12(-17) × 1.5-2(-2.5) μm; hila somewhat darkened and thickened, not refractive, 0.5-1 μm wide.

Cultural characteristics: Colonies erumpent, with sparse aerial mycelium and smooth margins on PDA, greyish sepia (surface); reverse fuscous-black; on OA patches of greyish sepia and fuscous-black (surface); on SNA umber (surface). Colonies reaching 15 mm diam on PDA after 1 mo at 25 °C in the dark; colonies fertile.

Specimen examined: Netherlands, Baarn, De Vuursche, needle of Pinus sylvestris (Pinaceae), 12 Apr. 1982, G.S. de Hoog, holotype CBS H-1610, culture ex-type CBS 463.82.

Notes: This fungus was originally maintained in the CBS collection as Anungitea uniseptata Matsush. In culture, however, only a pseudocladosporium-like state was observed. Conidiophores are reduced to conidiogenous cells, and have several apical loci as in Fusicladium, but are not subdenticulate; scars are somewhat darkened and thickened, not refractive. Conidia of F. africanum are (8-)11-17(-20) × 2-3(-3.5) μm, thus similar, but somewhat larger than the mean conidial size range (10-12 × 1.5-2 μm) observed in F. pini. The conidiogenous loci and conidial hila of F. africanum are also somewhat larger. Although the LSU sequence of F. pini is identical to that of F. ramoconidii, the ITS sequence similarity is 97 % (572/585 nucleotides).

Fusicladium ramoconidii Crous & de Hoog, sp. nov. MycoBank MB504541. Figs ​Figs2525-​-2626.

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Fig. 25.

Fusicladium ramoconidii (CBS 462.82). A. Colony on OA. B. Hyphal coil. C-F. Conidiophores reduced to conidiogenous cells. G-H. Conidiophores. I. Conidia. Scale bars = 10 μm.

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Fig. 26.

Fusicladium ramoconidii (CBS 462.82). Conidiogenous cells with ramoconidia and conidia. Scale bar = 10 μm.

Etymology: Named after the presence of its characteristic ramoconidia.

Fusicladio brevicatenato similis, sed ramoconidiis minoribus, (12-)15-17(-20) × 2(-3) μm, locis conidiogenis et hilis minoribus, 0.5-1 μm diam.

Mycelium consisting of branched, septate, 1.5-2 μm wide hyphae, pale brown, smooth, frequently with hyphal coils. Conidiophores integrated into hyphae, and reduced to small, lateral protruding conidiogenous cells, concolorous with hyphae, or macronematous, dark brown, erect, thick-walled, 10-40 × 3-4 μm, 0-3-septate. Conidiogenous cells terminal, integrated, subcylindrical, tapering to a rounded apex, concolorous with hyphae (as hyphal pegs), or dark brown on mononematous conidiophores, smooth, 3-15 × 2-3(-4) μm; proliferating sympodially, loci slightly thickened, darkened and refractive, 0.5-1 μm wide. Conidia occurring in branched chains, narrowly ellipsoid to subcylindrical, pale olivaceous, guttulate; ramoconidia (0-)1(-3)-septate, (12-)15-17(-20) × 2(-3) μm; conidia occurring in short chains (-15), 0-1-septate, (8-)10-12(-16) × 2(-3) μm; hila slightly thickened and darkened, not refractive, 0.5-1 μm wide.

Cultural characteristics: Colonies erumpent, with sparse aerial mycelium and smooth margins on PDA, hazel to fawn (surface), with a thin, submerged margin; reverse brown-vinaceous; on OA hazel to fawn (surface) with a wide, fawn, submerged margin. Colonies reaching 25 mm diam on PDA after 1 mo at 25 °C in the dark; colonies fertile.

Specimen examined: Netherlands, Baarn, De Vuursche, needle of Pinus sp. (Pinaceae), 12 Apr. 1982, G.S. de Hoog, holotype CBS H-19908, culture ex-type CBS 462.82.

Notes: This strain has been deposited in the CBS collection as Pseudocladosporium hachijoense (Matsush.) U. Braun. However, its ramoconidia and conidia are smaller than those cited by Matsushima (1975) (ramoconidia up to 30 μm long, conidia 10-21 × 2-4 μm). Although it clusters with F. pini in the LSU phylogeny, there are 13 bp differences in their ITS sequence data. Furthermore, F. ramoconidii has ramoconidia which are absent in F. pini, and has a faster growth rate, and hazel to fawn colonies, compared to the greyish sepia colonies of F. pini. The well-developed, septate conidiophores and ramoconidia are reminiscent of F. brevicatenatum, which differs, however, by its longer and wider ramoconidia, up to 30 × 6(-7) μm, as well as larger conidiogenous loci and conidial hila, 1.5-3 μm diam.

Fusicladium rhodense Crous & M.J. Wingf., sp. nov. MycoBank MB504542. Fig. 27.

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Fig. 27.

Fusicladium rhodense (CPC 13156). A. Colony on OA. B. Conidial chains and hyphal coil. C-F. Chains of ramoconidia and conidia. Scale bar = 10 μm.

Etymology: Named after the Greek Island, Rhodos, where it was collected.

Fusicladio africano similis, sed locis conidiogenis angustioribus, 1.5-2 μm latis, et differt a F. pini ramoconidiis formantibus.

Mycelium consisting of smooth to finely roughened, medium brown, branched, septate, 1.5-3 μm wide hyphae, frequently forming hyphal coils, giving rise to solitary, micronematous conidiophores. Conidiophores reduced to conidiogenous cells that are terminal or lateral on hyphae, medium brown, smooth, subcylindrical, subdenticulate, erect, or more distinct, up to 15 μm tall, 1.5-2 μm wide, mono- to polyblastic; scars flat-tipped, somewhat darkened and thickened, but not refractive. Conidia in branched or unbranched chains of up to 15, pale brown in younger conidia, becoming medium brown, smooth, subcylindrical, 0-3-septate, tapering slightly towards the subtruncate ends, straight, but at times slightly curved, (8-)12-16(-20) × (2-)2.5-3(-4) μm; ramoconidia (0-)1(-3)-septate, 12-20 × 3-4 μm; conidia (0-)1-septate, 8-17 × 2-3 μm; hila somewhat darkened and thickened, not refractive, 1-1.5 μm wide.

Cultural characteristics: Colonies spreading, somewhat erumpent, with moderate aerial mycelium and crenate margins on PDA, uneven, greyish sepia (surface), margins fuscous-black; reverse fuscous-black; on OA smooth, spreading, with sparse aerial mycelium and even, regular margins, greyish sepia; on SNA spreading, smooth, even margins, sparse aerial mycelium, greyish sepia (surface). Colonies reaching 9 mm diam on PDA after 2 wk at 25 °C in the dark; colonies fertile.

Specimen examined: Greece, Rhodos, on branches of Ceratonia siliqua (Fabaceae), 1 Jun. 2006, P.W. Crous & M.J. Wingfield, holotype CBS H-19910, culture ex-type CBS 121641 = CPC 13156.

Note: Fusicladium rhodense has a typical pseudocladosporium-like morphology in culture, with conidial scars that are somewhat darkened and thickened.

Venturia hanliniana (U. Braun & Feiler) Unter., Mycologia 89: 129. 1997.

Basionym: Capronia hanliniana U. Braun & Feiler, Microbiol. Res. 150: 90. 1995.

• ≡ Caproventuria hanliniana (U. Braun & Feiler) U. Braun, in Braun, A Monograph of Cercosporella, Ramularia and Allied Genera (Phytopathogenic Hyphomycetes) 2: 396. 1998.

Anamorph: Fusicladium brevicatenatum (U. Braun & Feiler) Crous, U. Braun & K. Schub., comb. nov. MycoBank MB504543.

Basionym: Cladophialophora brevicatenata U. Braun & Feiler, Microbiol. Res. 150: 84. 1995.

• ≡ Pseudocladosporium brevicatenatum (U. Braun & Feiler) U. Braun, in Braun, A Monograph of Cercosporella, Ramularia and Allied Genera (Phytopathogenic Hyphomycetes) 2: 393. 1998.

Venturia hystrioides (Dugan, R.G. Roberts & Hanlin) Crous & U. Braun, comb. nov. MycoBank MB504544. Fig. 28.

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Fig. 28.

Venturia hystrioides (CBS 117727). A. Conidiophores giving rise to catenulate conidia. B. Ramoconidium giving rise to conidia. C-D. Conidial chains. E. Conidia and conidiogenous cell with conidiogenous loci. F. Ramoconidium. G. Conidia. Scale bars = 10 μm.

Basionym: Capronia hystrioides Dugan, R.G. Roberts & Hanlin, Mycologia 87: 713. 1995.

• ≡ Caproventuria hystrioides (Dugan, R.G. Roberts & Hanlin) U. Braun, in Braun, A monograph of Cercosporella, Ramularia and allied genera (Phytopathogenic Hyphomycetes). Vol. 2: 396. 1998.

Anamorph: Fusicladium sp.

Only the anamorph was observed on OA, PDA and SNA in culture.

Mycelium consisting of branched, septate, smooth, guttulate, 1.5-2.5 μm wide hyphae, pale brown, forming hyphal strands. Conidiophores mostly reduced to conidiogenous cells, or if present, micronematous, consisting of a supporting cell, and single conidiogenous cell. Conidiogenous cells integrated in hyphae as lateral loci, or terminal, frequently disarticulating, subcylindrical, pale to medium brown, smooth, mono- to polyblastic, loci 1-1.5 μm wide, 2.5 μm tall; conidiogenous cells subcylindrical, up to 40 μm tall, and 2-2.5 μm wide. Conidia in long chains of up to 60, branched or not, subcylindrical to narrowly ellipsoid, pale olivaceous to pale brown, smooth; ramoconidia 0-1(-3)-septate, 15-20(-30) × 2-3(-3.5) μm; conidia 0(-1)-septate, 6-8(-12) × 2-3(-3.5) μm; hila 1-1.5 μm wide, inconspicuous to somewhat darkened, subtruncate.

Cultural characteristics: Colonies erumpent, with sparse aerial mycelium on PDA, and smooth, even margins; olivaceous-grey to iron-grey (surface); reverse greenish black; on OA dark mouse-grey (surface), with even, smooth margins. Colonies reaching 40 mm diam after 2 wk at 25 °C in the dark; colonies fertile.

Specimen examined: U.S.A., Washington, Wenatchee, on bing cherry fruit, Prunus avium cv. Bing (Rosaceae), R.G. Roberts, culture ex-type, ATCC 96019 = CBS 117727.

Note: Dugan et al. (1995) commented that although similar to “Phaeoramularia” hachijoensis, the conidia of this species were predominantly aseptate and somewhat shorter than those described by Matsushima (1975).