Statistical analysis

A heatmap showing the host distribution of each genus of Didymellaceae was generated with R v. 3.3.1 heatmap.2 (https://www.r-project.org/).

Taxonomy

As a result of morphological comparisons and multi-locus sequence analysis of 360 strains, including 108 strains studied in the present paper and 252 reference strains, 194 taxa are recognised in 19 different genera of Didymellaceae. Recognised clades of novel taxa are described and illustrated, and two new combinations are proposed below. One species proved to be sterile in culture, and therefore is described based on DNA sequence data, following the approach of Gomes et al. (2013) and Lombard et al. (2016). Novel taxa are arranged in alphabetical order by genus and species.

Allophoma Q. Chen & L. Cai, Stud. Mycol. 82: 162. 2015.

Allophoma oligotrophica Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818956. Fig. 3.

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Fig. 3

Allophoma oligotrophica (CGMCC 3.18114). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia producing on OA. H. Pycnidium. I. Section of pycnidium. J. Section of pycnidial wall. K. Conidiogenous cells. L. Conidia. Scale bars: G = 100 μm; H–I = 50 μm; J, L = 10 μm; K = 5 μm.

Etymology: Oligotrophica, referring to the oligotrophic substrate of the fungus.

Conidiomata pycnidial, solitary, globose to subglobose, brown, glabrous, semi-immersed or immersed, 150–440(–590) × 145–420 μm. Ostioles single, slightly papillate. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 3–5 layers, 11–19.5 μm thick. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 4.5–7 × 3.5–6.5 μm. Conidia oblong to cylindrical, smooth- and thin-walled, hyaline, aseptate, 3–4.5 × 1.5–2.5 μm, with 2 distinct pale green polar guttules. Conidia matrix whitish.

Culture characteristics: Colonies on OA, 45–50 mm diam after 7 d, margin regular, covered by white floccose aerial mycelia, white to pale olivaceous; reverse buff, with pale olivaceous concentric rings near the centre. Colonies on MEA 50–55 mm diam after 7 d, margin regular, aerial mycelia sparse, olivaceous, white near the centre; reverse olivaceous. Colonies on PDA, 50–55 mm diam after 7 d, margin regular, covered by dense white felty aerial mycelia, white, olivaceous near the centre; reverse buff, olivaceous near the centre. NaOH test negative.

Specimens examined: China, Guizhou, Shuanghe Cave National Geopark, from air, 8 May 2015, Z.F. Zhang (holotype HMAS 247035, dried culture, ex-holotype living culture CGMCC 3.18114 = LC 6245); ibid. CGMCC 3.18115 = LC 6246; ibid. CGMCC 3.18116 = LC 6247.

Notes: Species of Allophoma were hitherto all known as plant pathogens, while Al. oligotrophica is the first species which was isolated from air using carbon-free silica gel medium (Jiang et al. 2017). Allophoma oligotrophica is closely related to Al. nicaraguensis (1 bp difference in ITS, 14 in rpb2 and 3 in tub2) and Al. tropica (1 bp difference in ITS, 15 in rpb2 and 2 in tub2) (Fig. 1). Morphologically, Al. oligotrophica produces larger pycnidia (150–440 × 145–420 μm vs. 30–150 × 28–120 μm) and longer conidiogenous cells (4.5–7 × 3.5–6.5 μm vs. 3–4.5 × 3.5–4.5 μm) than Al. nicaraguensis (Chen et al. 2015a), and differs from Al. tropica in its slightly larger conidiogenous cells (4.5–7 × 3.5–6.5 μm vs. 2–6 × 3–6 μm) and oblong to cylindrical conidia (de Gruyter & Noordeloos 1992).

Ascochyta Lib. emend. Q. Chen & L. Cai. Stud. Mycol. 82: 185. 2015.

Synonym: Heracleicola Tibpromma et al., Fungal Divers. 75: 58. 2015.

Ascochyta boeremae L.W. Hou, Crous & L. Cai, sp. nov. MycoBank MB820000. Fig. 4.

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Fig. 4

Ascochyta boeremae (CBS 372.84). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidium. I. Section of pycnidium. J. Section of pycnidial wall. K–L. Conidiogenous cells. M–N. Conidia. Scale bars: G = 300 μm; H–I = 50 μm; J–N = 10 μm.

Etymology: Named after Gerhard H. Boerema, who collected the holotype of this species.

Conidiomata pycnidial, mostly solitary, sometimes confluent, (sub-)globose or flask-shaped, glabrous, semi-immersed in or superficial on the agar, ostiolate, 170–550(–650) × 140–400(–650) μm. Ostiole single, slightly papillate, sometimes elongated as a short neck. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 3–6-layers, with outer 2–3-layers pigmented, 25–50 μm thick. Conidiogenous cells phialidic, hyaline, smooth, ampulliform or doliiform, 9.5–14.5 × 8.5–13 μm. Conidia greatly variable in shape and size, large conidia mostly oblong to bacilliform, or fusiform, mainly aseptate but sometimes uniseptate; small conidia ellipsoidal to oval, broadly ovoid, smooth- and thin-walled, hyaline, aseptate, (14–)16.5–26(–32) × 4.5–7.5(–8.5) μm, eguttulate or sometimes with 1–2 guttules per cell. Conidial matrix whitish cream.

Culture characteristics: Colonies on OA, 25–30 mm diam after 7 d, margin regular, covered by sparsely flat aerial mycelia, yellowish olivaceous; reverse concolourous. Colonies on MEA 20–25 mm diam after 7 d, margin regular, covered with floccose aerial mycelia, white, grey near the centre; reverse sienna to pale brown. Colonies on PDA, 15–20 mm diam after 7 d, margin regular, covered by woolly aerial mycelia, greenish olivaceous, buff near the margin; reverse concolourous. NaOH spot test: a dark reddish brown discolouration on MEA.

Specimens examined: Australia, from a leaf of Pisum sativum, deposited in CBS Sep. 1984, G.H. Boerema (holotype CBS H-23017, dried culture, ex-holotype living culture CBS 372.84 = PD 80/1246); from a leaf of Pisum sativum, deposited in CBS Sep. 1984, G.H. Boerema, CBS H-9078, culture CBS 373.84 = PD 80/1247.

Notes: CBS 372.84 and CBS 373.84 were originally deposited as “Ascochyta fabae”, but are distinct from the authentic cultures of As. fabae (CBS 524.77, CBS 649.71 and PD 83/492) in the phylogenetic tree. Morphologically, these two strains produce aseptate conidia differing from the uniseptate conidia of As. fabae (Saccardo 1902). Therefore, we describe it as a new species, As. boeremae. Ascochyta boeremae is genetically closely related to As. nigripycnidia (Fig. 1), but differs morphologically from the latter by producing larger conidia (14–32 × 4.5–8.5 μm vs. 5.5–15 × 1.5–4 μm; Boerema et al. 2004).

Ascochyta premilcurensis (Tibpromma et al.) Q. Chen, Crous & L. Cai, comb. nov. MycoBank MB820001.

Basionym: Heracleicola premilcurensis Tibpromma et al., Fungal Divers. 75: 59. 2015.

Description: Ariyawansa et al. (2015).

Specimen examined: Italy, Premilcuore, Province of Forli-Cesena, Valbura, on dead stem of Heracleum sphondylium, 6 Jun. 2014, E. Camporesi (holotype MFLU 14-0725, ex-holotype living culture MFLUCC 14-0518).

Notes: The genus Heracleicola was introduced by Ariyawansa et al. (2015) to accommodate a single species Heracleicola premilcurensis, which is located in the genus Ascochyta based on combined LSU and ITS analysis (Supplementary Fig. S1) in the present study. Heracleicola is therefore synonymised under Ascochyta, and a new combination in Ascochyta proposed.

Boeremia Aveskamp et al., Stud. Mycol. 65: 36. 2010.

Boeremia exigua var. opuli Q. Chen, Crous & L. Cai, var. nov. MycoBank MB818957. Fig. 5.

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Fig. 5

Boeremia exigua var. opuli (CGMCC 3.18354). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Section of pycnidial wall. I–J. Conidiogenous cells. K. Conidia. Scale bars: G = 400 μm; H–J = 5 μm; K = 10 μm.

Etymology: Named after the host species from which the holotype was collected, Viburmum opulus.

Conidiomata pycnidial, solitary or aggregated, globose to subglobose, brown, covered with hyphae, produced on the agar surface or (semi-)immersed, 245–360 × 200–305 μm. Ostiole single, slightly papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 4–5 layers, 20–37.5 μm thick. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 4–9(–10) × 4–7.5 μm. Conidia oblong to cylindrical, obovoid, incidentally slightly curved, or reniform, smooth- and thin-walled, hyaline, aseptate, 5.5–9.5 × 2.5–4 μm, with 2 or several minute guttules. Conidia matrix cream.

Culture characteristics: Colonies on OA, 70–76 mm diam after 7 d, margin regular, covered by white floccose aerial mycelia, white with a pale green concentric ring, pale olivaceous near the centre; reverse reddish brown, grey near the centre. Colonies on MEA 70–75 mm diam after 7 d, margin regular, aerial mycelia white, velvety, olivaceous; reverse concolourous. Colonies on PDA, 65–80 mm diam after 7 d, margin regular, aerial mycelia white, felty, in some sectors covered by a low mat of floccose white to grey aerial mycelia, olivaceous near the centre; reverse olivaceous, with a buff margin. Application of NaOH results in a pale green discolouration of the agar.

Specimens examined: USA, from seedlings of Viburmum opulus, 2014, W.J. Duan (holotype HMAS 247147, dried culture, ex-holotype living culture CGMCC 3.18354 = LC 8117); ibid. LC 8118.

Notes: Boeremia exigua var. opuli is phylogenetically closely related to B. exigua var. exigua, B. exigua var. forsythiae, B. exigua var. glivescens and B. exigua var. viburni (Fig. 1). Although similar in conidial dimensions, pycnidia of B. exigua var. opuli (245–360 × 200–305 μm) are much larger than those of the other four varieties (75–200 μm; van der Aa et al. 2000). Boeremia exigua var. opuli also differs from those four varieties in seven positions in the rpb2 locus. Varieties of B. exigua are morphologically very similar and phylogenetically closely related to each other. Boeremia exigua var. exigua and var. forsythia have a wide host range, while other varieties appear host specific to a certain group of plants, such as var. coffeae to Coffea arabica (Rubiaceae), var. forsythia to Forsythia hybrids (Oleaceae), var. heteromorpha to Nerium oleander and Vinca spp. (Apocynaceae), var. linicola to Linum usitatissimum (Linaceae), var. populi to Populus and Salix (Salicaceae), and var. viburni to Viburnum spp. and occasionally Lonicera sp. (Caprifoliaceae) (Boerema et al. 2004). Besides, B. exigua var. pseudolilacis has been found only on Syringa vulgaris (Oleaceae; Aveskamp et al. 2010) and var. opuli only on Viburnum opulus. A host-range determination of B. exigua var. rhapontica indicates that this variety also has a very narrow host range (Berner et al. 2015). Thus, the plant generic inter-relatedness is presumed to be the basis for susceptibility to Boeremia exigua varieties (Berner et al. 2015).

Calophoma Q. Chen & L. Cai, Stud. Mycol. 82: 191. 2015.

Calophoma rosae Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818976. Fig. 6A.

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Fig. 6

Calophoma rosae (CGMCC 3.18347). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidia. I. Section of pycnidium. J. Section of pycnidial wall. K. Conidiogenous cells. L. Conidia. Scale bars: G = 100 μm; H = 40 μm; I–L = 10 μm.

Etymology: Named after the host genus Rosa, from which the holotype was isolated.

Leaf spots amphigenous, circular to irregular, up to 15 mm diam, occurring on or close to the tip of the leaf, brown, surrounded by a dark purple border (Fig. 7). Conidiomata pycnidial, mostly aggregated but sometimes solitary, globose to subglobose, brown, glabrous or covered with some hyphal outgrowths, semi-immersed in or superficial on the agar, ostiolate, (110–)130–210 × (110–)130–180 μm. Ostiole single, sometimes with short necks, slightly papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 3–4 layers, 11–20 μm thick, pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 6.5–7 × 7–8.5 μm. Conidia ellipsoidal to oblong, smooth- and thin-walled, 0–1-septate, hyaline, later becoming pale brown with ageing, 6–10 × 3–4.5 μm, eguttulate or sometimes with several guttules. Conidial matrix initially buff, gradually becoming dark brown.

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Fig. 7

Symptoms on diseased leaves. A.Calophoma rosae on Rosa sp. B.Didymella infuscatispora on Chrysanthemum indicum. C.Didymella ocimicola on Ocimum sp. D.Didymella sinensis on Cerasus pseudocerasus. E.Epicoccum dendrobii on Dendrobium fimbriatum. F.Epicoccum duchesneae on Duchesnea indica. G.Stagonosporopsis bomiensis on Boraginaceae. H.Epicoccum viticis on Vitex negundo. I.Epicoccum layuense on Perilla sp. J.Heterophoma verbascicola on Verbascum thapsus. K.Stagonosporopsis papillata on Rumex nepalensis.

Culture characteristics: Colonies on OA, 35–40 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, dense, white; reverse buff. Colonies on MEA 33–35 mm diam after 7 d, margin regular, aerial mycelia sparse, flattened, white; reverse concolourous. Colonies on PDA, 30–36 mm diam after 7 d, margin regular, aerial mycelia covering the whole colony, floccose, dense, white; reverse yellowish green, with concentric rings. NaOH test negative.

Specimens examined: China, Qinghai, Xunhua, from leaves of Rosa sp., 2 Sep. 2013, Q. Chen (holotype HMAS 247148, dried culture, ex-holotype living culture CGMCC 3.18347 = LC 5169); ibid. LC 8119.

Notes: Calophoma rosae is phylogenetically closely related to C. clematidis-rectae and C. vodakii (Fig. 1). Morphologically C. rosae differs from C. clematidis-rectae in having larger conidiogenous cells (6.5–7 × 7–8.5 μm vs. 3–5 × 2.5–4.5 μm), larger conidia (6–10 × 3–4.5 μm vs. 3–8 × 2–3.5 μm) (Aveskamp et al. 2010), and from C. vodakii in having shorter and wider conidia (6.5–7 × 7–8.5 μm vs. 14–22 × 4–4.5 μm; Saccardo and Trotter, 1913, Müller, 1953).

Calophoma rosae is the first and only record thus far from the Rosaceae, while most species in this genus are associated with species of Ranunculaceae.

Didymella Sacc. ex Sacc., Syll. Fung. 1: 545. 1882, emend. Q. Chen & L. Cai, Stud. Mycol. 82: 173. 2015.

Didymella aeria Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818968. Fig. 8.

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Fig. 8

Didymella aeria (CGMCC 3.18353). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidia. I. Section of pycnidium. J. Section of pycnidial wall. K. Conidia. Scale bars: G = 200 μm; H = 30 μm; I = 20 μm; J–K = 10 μm.

Etymology: Name linked to the fact that this species was collected from air.

Conidiomata pycnidial, solitary or aggregated, globose to subglobose, later becoming irregular, brown, glabrous, superficial or semi-immersed, 155–375(–460) × 130–340(–460) μm. Ostiole single, with a short neck, slightly papillate or non-papillate. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 2–3 layers, 8.5–25 μm thick, brown-pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 5–7 × 4.5–6 μm. Conidia ellipsoidal, smooth- and thin-walled, hyaline, aseptate, 3–5 × 2–3 μm, with 2 large dull green polar guttules. Conidial matrix salmon.

Culture characteristics: Colonies on OA, 55–60 mm diam after 7 d, margin regular, white aerial mycelia sparse, brownish olivaceous; reverse white to reddish brown. Colonies on MEA 44–48 mm diam after 7 d, margin regular, white to olivaceous, with sparse white aerial mycelia spreading over the colony; reverse concolourous. Colonies on PDA, 15–20 mm diam after 7 d, margin irregular, fluffy to felty, white; reverse amber to saffron. NaOH spot test: a brown discolouration on MEA.

Specimens examined: China, Guizhou, Zunyi, Shuanghe Cave National Geopark, from air, 8 May 2015, Z.F. Zhang (holotype HMAS 247149, dried culture, ex-holotype living culture CGMCC 3.18353 = LC 7441); ibid. LC 8120.

Notes: The most closely related species to Didymella aeria are D. sinensis and D. pomorum (Fig. 1), but with respectively 33 bp and 55 bp differences in four sequenced loci. Didymella aeria produces hyaline conidia measuring 3–5 × 2–3 μm, while D. pomorum produces longer, brown conidia (4–8 × 1.5–3 μm; Boerema 1993). The asexual morph of D. sinensis was unfortunately not observed. Didymella aeria was trapped from air in a Karst cave in China.

Didymella aquatica Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818973. Fig. 9.

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Fig. 9

Didymella aquatica (CGMCC 3.18349). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia sporulating on OA. H. Pycnidia. I. Section of pycnidium. J. Section of pycnidial wall. K. Conidia. Scale bars: G = 100 μm; H = 50 μm; I, K = 10 μm; J = 5 μm.

Etymology: Name derived from the substrate where the holotype was collected, water.

Conidiomata pycnidial, solitary, sometimes aggregated, globose to subglobose, brown, glabrous or covered with some hyphal outgrowths, superficial, ostiolate, 105–355 × 95–315 μm. Ostioles 2–13, sometimes elongated as a short neck, up to 50.5 μm long, papillate. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 2–5 layers, 14–35 μm thick, outer wall 2–3-layers pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 4–5 × 3.5–5 μm. Conidia ellipsoidal to oblong, smooth- and thin-walled, hyaline, aseptate, 4–5.5 × 2–3 μm, with 2 distinct polar guttules. Conidial matrix cream.

Culture characteristics: Colonies on OA, 15–40 mm diam after 7 d, margin regular, covered by velvety aerial mycelia, flat, white to amber; reverse concolourous. Colonies on MEA 46–53 mm diam after 7 d, margin regular, white to pale green, with sparse aerial mycelia near the centre; reverse concolourous. Colonies on PDA, 54–56 mm diam after 7 d, margin regular, floccose to felty, white to grey, iron grey near the centre; reverse white, hazel to brown. NaOH test negative.

Specimens examined: China, Guizhou, Kuankuoshui National Geopark, water, 23 Jul. 2014, Z.F. Zhang (holotype HMAS 247150, dried culture, ex-holotype living culture CGMCC 3.18349 = LC 5556); ibid. LC 5555.

Notes: Didymella aquatica formed a distinct lineage sister to D. macrophylla, with 6 bp differences in both rpb2 and tub2 loci. Morphologically, D. aquatica is clearly differentiated from D. macrophylla in producing smaller conidiogenous cells (4–5 × 3.5–5 μm vs. 6–8 × 4.5–8 μm), longer and narrower conidia (4–5.5 × 2–3 μm vs. 1.5–2.5 × 3.5–5.5 μm), and in the number of conidiomatal ostioles (2–13 vs. 1). This is the first Didymella species known from water.

Didymella chloroguttulata Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818970. Fig. 10.

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Fig. 10

Didymella chloroguttulata (CGMCC 3.18351). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Section of pycnidial wall. I. Conidia. Scale bars: G = 200 μm; H–I = 10 μm.

Etymology: Latin, chloro- = green, referring to the two green guttules of the conidia.

Conidiomata pycnidial, confluent, globose to subglobose, brown, glabrous, superficial, 145–260(–410) × 130–230(–365) μm. Ostiole single, sometimes with a short neck, slightly papillate or non-papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 3–4 layers, 14.5–22 μm thick, pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 5.5–8 × 4–6.5 μm. Conidia oblong to cylindrical, incidentally slightly curved, smooth- and thin-walled, hyaline, aseptate, 4–6 × 2–3 μm, with 2–3 dull green polar guttules. Conidial exudates not recorded.

Culture characteristics: Colonies on OA, 54–57 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, dense, grey; reverse black. Colonies on MEA 44–47 mm diam after 7 d, margin regular, white aerial mycelia sparse, fluffy, greenish brown; reverse concolourous. Colonies on PDA, 57–62 mm diam after 7 d, margin regular, floccose, grey to leaden-black; reverse leaden-black. NaOH spot test: a pale reddish brown discolouration on MEA.

Specimens examined: China, Guizhou, Zunyi, Shuanghe Cave National Geopark, air, 8 May 2015, Z.F. Zhang (holotype HMAS 247151, dried culture, ex-holotype living culture CGMCC 3.18351 = LC 7435); ibid. LC 8122.

Notes: Didymella chloroguttulata is characterised by having two to three dull green polar guttules in its oblong to cylindrical conidia and sometimes having conidiomata with a short neck. In the phylogenetic tree, it formed a distinct clade sister to D. dactylidis and D. rhei (Fig. 1). Didymella chloroguttulata is well distinguished from these two species in the NaOH reactions (pale reddish brown discolouration on D. chloroguttulata, slight greenish discolouration on D. dactylidis, and no effect on D. rhei) (de Gruyter et al. 2002, Aveskamp et al. 2010).

Didymella ellipsoidea Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818971. Fig. 11.

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Fig. 11

Didymella ellipsoidea (CGMCC 3.18350). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia sporulating on OA. H. Pycnidia. I. Ostioles on pycnidium. J. Section of pycnidium. K. Section of pycnidial wall. L. Conidia. Scale bars: G = 100 μm; H = 50 μm; I, K–L = 10 μm; J = 20 μm.

Etymology: Name refers to its ellipsoidal conidia.

Conidiomata pycnidial, solitary, globose to subglobose, brown, glabrous or covered with some hyphal outgrowths, superficial, ostiolate, 335–400(–460) × 290–340(–440) μm. Ostioles 1–8, often developing to elongated short necks, up to 80 μm long, papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 3–5 layers, 23.5–50 μm thick, pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 5.5–7.5 × 4.5–6.5 μm. Conidia ellipsoidal, smooth- and thin-walled, hyaline, aseptate, 3–4.5 × 2–3 μm, with 2 pale green guttules. Conidial matrix cream.

Culture characteristics: Colonies on OA, 56–62 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, dense, white to pale brown; reverse white to greenish brown. Colonies on MEA 61–64 mm diam after 7 d, margin regular, white aerial mycelia sparse, fluffy, grey to olivaceous; reverse concolourous. Colonies on PDA, 52–54 mm diam after 7 d, margin regular, floccose, grey to leaden-black, with a white concentric ring near the centre; reverse concolourous. NaOH test negative.

Specimen examined: China, Guizhou, Zunyi, Shuanghe Cave National Geopark, air, 8 May 2015, Z.F. Zhang (holotype HMAS 247152, dried culture, ex-holotype living culture CGMCC 3.18350 = LC 7434); ibid. LC 8123.

Notes: This species is represented by two isolates trapped from air in a Karst cave which cluster in a distinct lineage clearly differentiated from other species in Didymella (Fig. 1). Morphologically, Didymella ellipsoidea is distinguishable from its closest neighbours, D. viburnicola, in producing wider conidia (3–4.5 × 2–3 μm vs. 3.5–5.5 × 1.5–2 μm; de Gruyter & Noordeloos 1992), from D. macrostoma in having shorter conidia (3–4.5 × 2–3 μm vs. 4–11 × 2–4 μm; de Gruyter et al. 2002), and from D. pteridis in producing larger conidiogenous cells (5.5–7.5 × 4.5–6.5 μm vs. 4–5 × 3.5–4.5 μm).

Didymella ilicicola Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818969. Fig. 12.

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Fig. 12

Didymella ilicicola (CGMCC 3.18355). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidium. I. Section of pycnidium. J. Section of pycnidial wall. K–L. Conidiogenous cells. M. Conidia. Scale bars: G = 100 μm; H = 20 μm; I–J = 10 μm; K–M = 5 μm.

Etymology: Name derived from Ilex, the plant from which the holotype was collected.

Conidiomata pycnidial, solitary or aggregated, (sub-)globose to flask-shaped, or obpyriform, brown, later becoming irregular when matured, covered with hyphal outgrowths, mostly erumpent, sometimes semi-immersed, ostiolate, (80–)150–200 × (70–)150–180 μm. Ostioles 2–3, elongated as short papillate necks. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 2–5 layers, 15–20 μm thick, outer wall 2–3-layers pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 4.5–8 × 3.5–5 μm. Conidia ellipsoidal to oblong, smooth- and thin-walled, hyaline, aseptate, 3–4 × 1.5–2.5 μm, with two minute guttules. Conidial matrix cream to buff.

Culture characteristics: Colonies on OA, 43–50 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, white to pale buff, with a dull green concentric ring near the centre; reverse reddish brown to buff, with a brown concentric ring. Colonies on MEA 56–65 mm diam after 7 d, margin irregular, white, aerial mycelia sparse; reverse concolourous. Colonies on PDA, 62–65 mm diam after 7 d, margin regular, felty to floccose, dense, white to pale yellow; reverse white to buff with some pale reddish brown tings in concentric rings. NaOH test negative.

Specimens examined: Italy, from seedlings of Ilex chinensis, 2013, W.J. Duan (holotype HMAS 247153, dried culture, ex-holotype living culture CGMCC 3.18355 = LC 8126); ibid. LC 8127.

Notes: Didymella ilicicola clustered in a clade together with D. subherbarum and D. pedeiae (Fig. 1), but with 1 bp and 9 bp differences in ITS and tub2 respectively from D. subherbarum (lack of rpb2 sequence), and 26 bp and 12 bp differences in rpb2 and tub2 respectively from D. pedeiae. Morphologically, D. ilicicola differs from D. subherbarum in producing shorter conidia (3–4 × 1.5–2.5 μm vs. 4–6.5 × 1.5–2 μm; de Gruyter et al. 1993), and from D. pedeiae in producing larger conidiogenous cells (4.5–8 × 3.5–5 μm vs. 3.5–4.5 × 3–4 μm; Aveskamp et al. 2010).

Didymella infuscatispora Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818974. Fig. 13.

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Fig. 13

Didymella infuscatispora (CGMCC 3.18356). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidia. I. Conidia. J. Conidiogenous cell. Scale bars: G = 200 μm; H = 50 μm; I = 10 μm; J = 2.5 μm.

Etymology: Latin, infuscat- = brownish, referring to the colour of its conidia.

Leaf spots amphigenous, irregular, 3–11 mm diam, extending along leaf margin to the whole leaf, dark grey to dark brown (Fig. 7B). Conidiomata pycnidial, solitary, globose to subglobose, brown, later becoming irregular when matured, covered with some hyphal outgrowths, superficial, ostiolate, (50–)95–265 × (20–)75–165 μm. Ostiole single, sometimes elongated as short necks, slightly papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 2–3 layers, 13.5–23 μm thick. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 6–8.5 × 5.5–8 μm. Conidia globose to broadly ellipsoidal, oblong, smooth- and thin-walled, hyaline, later becoming pale brown, mostly aseptate, occasionally 1-septate, 5–8.5 × 3.5–5.5 μm, with several indistinct minute guttules. Conidial matrix dark brown.

Culture characteristics: Colonies on OA, 15–20 mm diam after 7 d, margin regular, covered by felty aerial mycelia, white to buff, pale brown near the centre; reverse white to amber, hazel near the centre. Colonies on MEA 10–15 mm diam after 7 d, margin irregular, aerial mycelia sparse, white to pale green; reverse white to pale green, yellowish brown near the centre. Colonies on PDA, 14–16 mm diam after 7 d, margin regular, aerial mycelia felty, flat, white to pale brown; reverse buff to brown. NaOH test negative.

Specimens examined: China, Tibet, Lulang, on leaves of Chrysanthemum indicum, 15 Jun. 2015, Q. Chen (holotype HMAS 247154, dried culture, ex-holotype living culture CGMCC 3.18356 = LC 8128); ibid. LC 8129.

Note: This species clustered in a distinct lineage separated from other species in this genus, and is characterised by pale brown and broadly ellipsoidal conidia and a dark brown conidial matrix when mature.

Didymella macrophylla Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB819189. Fig. 14.

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Fig. 14

Didymella macrophylla (CGMCC 3.18357). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidia. I. Conidia. Scale bars: G = 200 μm; H–I = 10 μm.

Etymology: Named after the host species Hydrangea macrophylla, from which the holotype was collected.

Conidiomata pycnidial, mostly solitary, sometime aggregated, globose to subglobose, pale brown, glabrous, semi-immersed or immersed in agar, ostiolate, (80–)120–200 × (60–)100–150 μm. Ostiole single, slightly papillate. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 1–2 layers, 7–15 μm thick, pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 6–8 × 4.5–8 μm. Conidia obovoid, ellipsoidal to oblong, smooth- and thin-walled, hyaline, aseptate, 3.5–5.5 × 1.5–2.5 μm, with two polar guttules. Conidial matrix buff.

Culture characteristics: Colonies on OA, 44–46 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, white to grey, yellowish grey near the centre; reverse grey to greyish yellow. Colonies on MEA 54–60 mm diam after 7 d, margin regular, covered by white aerial mycelia, fluffy; reverse concolourous. Colonies on PDA, 59–68 mm diam after 7 d, margin regular, aerial mycelia floccose, dense, white to yellowish grey; reverse dark brown with pale olivaceous margin. NaOH test negative.

Specimens examined: Italy, Hydrangea macrophylla, 2013, W.J. Duan (holotype HMAS 247155, dried culture, ex-holotype living culture CGMCC 3.18357 = LC8131); ibid. LC 8132.

Note: Didymella macrophylla is phylogenetically most closely related to D. aquatica (Fig. 1), which is discussed under the notes of the latter species.

Didymella ocimicola Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB819127. Fig. 15.

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Fig. 15

Didymella ocimicola (CGMCC 3.18358). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Section of pycnidium. I. Conidia. Scale bars: G = 100 μm; H = 50 μm; I = 10 μm.

Etymology: Name derived from Ocimum, the plant host from which the holotype was collected.

Leaf spots amphigenous, irregular, 8–15 mm diam, next to or close to the leaf margin, pale brown (Fig. 7C). Conidiomata pycnidial, solitary, sometimes aggregated, globose to flask-shaped, brownish olivaceous, covered by some hyphal outgrowths, superficial or semi-immersed, ostiolate, 100–235 × 95–180 μm. Ostiole single, with an elongated neck, slightly papillate or non-papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 2–5 layers, 12–35.5 μm thick, brown-pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 5–5.5 × 3.5–5 μm. Conidia globose to broadly ellipsoidal, smooth- and thin-walled, hyaline, aseptate, 4–6.5 × 3–4.5 μm, with one to several distinct guttules. Conidial exudates not recorded.

Culture characteristics: Colonies on OA, 10–15 mm diam after 7 d, margin regular, aerial mycelia floccose, flat, white to buff; reverse concolourous. Colonies on MEA 9–12 mm diam after 7 d, margin irregular, aerial mycelia floccose, white, dull green; reverse white to dull green. Colonies on PDA, 10–15 mm diam after 7 d, margin regular, aerial mycelia floccose, white; reverse olivaceous with white to pale brown patches. NaOH test negative.

Specimens examined: China, Tibet, Lulang, on leaves of Ocimum sp., 15 Jun. 2015, Q. Chen (holotype HMAS 247156, dried culture, ex-holotype living culture CGMCC 3.18358 = LC 8137); ibid. LC 8138.

Notes: Didymella ocimicola grouped closely with D. chenopodii and D. senecionicola (Fig. 1), but differs from D. chenopodii in smaller conidiogenous cells (5–5.5 × 3.5–5 μm vs. 4–8 × 4–6 μm) and wider conidia (4–6.5 × 3–4.5 μm vs. 5–5.5 × 2–2.2 μm) and from D. senecionicola in wider conidia (4–6.5 × 3–4.5 μm vs. 4–6.5 × 1.5–2.5 μm) (de Gruyter et al. 1993). Didymella ocimicola has 44 bp and 30 bp differences in three loci (lack of rpb2 sequence) from D. chenopodii and D. senecionicola respectively.

Didymella pteridis L.W. Hou, Crous & L. Cai, sp. nov. MycoBank MB820002. Fig. 16.

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Fig. 16

Didymella pteridis (CBS 379.96). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidium. I. Section of pycnidium. J. Section of pycnidial wall. K. Conidiogenous cells. L. Conidia. Scale bars: G = 300 μm; H = 40 μm; I = 20 μm; J–L = 10 μm.

Etymology: Named after the host genus Pteris, from which the holotype was collected.

Conidiomata pycnidial, mainly solitary, sometimes aggregated, (sub-)globose or flask-shaped, glabrous or with some mycelial outgrowths, superficial or semi-immersed, ostiolate, 170–350(–430) × 150–330 μm. Ostiole single, papillate, sometimes elongated as a short neck, with dark colour near the ostioles. Pycnidial wall pseduoparenchymatous, composed of oblong to isodiametric cells, 3–6 layers, 9–28 μm thick, with outer 1–2-layers pigmented. Conidiogenous cell phialidic, hyaline, smooth, ampulliform to doliiform, 4–5 × 3.5–4.5 μm. Conidia ovoid to broadly oval, smooth- and thin-walled, hyaline, aseptate, (3–)4–6 × 2.5–3.5 μm, with two polar guttules. Conidial matrix pale salmon.

Culture characteristics: Colonies on OA, 58–60 mm diam after 7 d, margin regular, aerial mycelia flat, cinnamon to hazel, mycelia sparse in some furrowed zone, pycnidia abundant near the margin; reverse buff to pale olivaceous. Colonies on MEA 20–25 mm diam after 7 d, margin regular, aerial mycelia floccose, white, grey near the centre, pale salmon conidial matrix appeared near the centre; reverse yellow in outer ring, changing towards the centre from saffron, hazel, greyish brown to brown. Colonies on PDA, 65–68 mm diam after 7 d, margin regular, densely covered by floccose aerial mycelia, greenish brown, with some white mycelial pellets scattering over the colony; reverse dark brown, buff near the margin. NaOH spot test: a pale reddish brown discolouration on MEA.

Specimen examined: The Netherlands, Wageningen, Alphen aan de Rijn, from a leaf of Pteris sp., deposited in CBS Apr. 1996 (holotype CBS H-23013, dried culture, ex-holotype living culture CBS 379.96).

Notes: CBS 379.96 was originally identified as “Didymella adianticola”, which is currently a synonym of Paraboeremia adianticola. CBS 379.96 is well distinguished from Pa. adianticola both in morphology and phylogeny. Didymella pteridis produces pycnidia with a single ostiole and shorter conidiogenous cells (4–5 × 3.5–4.5 μm), different from Pa. adianticola (pycnidia with 1–3 ostioles, conidiogenous cells 5.5–7 × 3–6.5 μm; Chen et al. 2015a). Thus, we introduce CBS 379.96 as a new species, D. pteridis. Didymella pteridis is closely related to D. viburnicola in the multi-locus phylogenetic analyses (Fig. 1), but D. pteridis is differentiated from the latter by wider conidia (3–6 × 2.5–3.5 μm vs. 3.6–5.6 × 1.6–2.2 μm) and the colour of its conidial matrix (pale salmon vs. whitish) (de Gruyter & Noordeloos 1992).

Didymella segeticola (Q. Chen) Q. Chen, Crous & L. Cai, comb. nov. MycoBank MB819327.

Basionym: Phoma segeticola Q. Chen, Phytotaxa 197: 274. 2015.

Description: Chen et al. (2015b).

Specimens examined: China, Hubei, Shennongjia Forest Region, on diseased leaves of Cirsium segetum, 1 Aug. 2011, K. Zhang (holotype HMAS 245746, ex-holotype living culture CGMCC 3.17489); ibid. CGMCC 3.17498 = LC 1635; ibid. LC 1633; ibid. LC 1634.

Notes: This species was introduced as Phoma segeticola, before the comprehensive revision of Didymellaceae (Chen et al. 2015b). Under current circumstance of Didymellaceae, it belongs to Didymella. Didymella segeticola is closely related to D. bellidis, and has 12 bp differences in four loci from the latter. Morphologically, D. segeticola could be distinguished from the latter in producing wider conidia (4.5–7 × 2.5–4 μm vs. 4–6.5 × 2–2.5 μm; Chen et al. 2015b).

Didymella sinensis Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818967. Fig. 17.

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Fig. 17

Didymella sinensis (CGMCC 3.18348). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Section of pseudothecial wall. H. Asci forming in ascomata. I–J. Asci. K–N. Ascospores. Scale bar: G–H = 10 μm; I–K, M = 5 μm; L, N = 2.5 μm.

Etymology: Epithet derived from the country of origin, China.

Leaf spots amphigenous, angular to irregular, 3–5 mm diam, scatter over the leaf, dark brown to black (Fig. 7D). Ascomata aggregated, globose to irregular, brown, small, up to 170 μm diam, papillate. Pseudothecial wall 18–29.5 μm thick, outer wall consisting of 2–5 layers of cells of textura angularis. Pseudoparaphyses hyaline, 1.5–2 μm diam, septate. Asci bitunicate, clavate to short cylindrical, 32–52 × 8.5–16 μm. Ascospores biseriate, ellipsoidal, straight to slightly curved, 12–18 × 4.5–7.5 μm, hyaline, smooth, apex obtuse, base broadly obtuse to subobtuse, medianly 1-septate, upper cell often wider than lower cell, slightly constricted at the septum.

Culture characteristics: Colonies on OA, 49–52 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, grey to black; reverse black. Colonies on MEA 57–60 mm diam after 7 d, margin regular, greyish brown; reverse concolourous. Colonies on PDA, 56–60 mm diam after 7 d, margin regular, pale grey, with brownish olivaceous margin; reverse dark brown. NaOH spot test: a hazel discolouration on MEA.

Specimens examined: China, Guizhou, Huangguoshu waterfall, on leaves of Cerasus pseudocerasus, 21 Jul. 2014, Q. Chen (holotype HMAS 247157, dried culture, ex-holotype living culture CGMCC 3.18348 = LC 5210); Guizhou, Kuankuoshui National Geopark, Urticaceae, 20 Jul. 2014, Q. Chen, LC 5246; Guizhou, Xingyi, on leaves of Dendrobium officinale, 4 Jul. 2015, Q. Chen, LC 8142; ibid. LC 8143.

Notes: Didymella sinensis has only been observed as a sexual morph, which is not common among species of Didymellaceae. Four isolates from diseased leaves of three host plants in different families were collected, i.e. Cerasus pseudocerasus (Rosaceae), Dendrobium officinale (Orchidaceae) and Urticaceae, indicating an opportunistic pathogen with very broad host range.

Didymella suiyangensis Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818972. Fig. 18.

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Fig. 18

Didymella suiyangensis (CGMCC 3.18352). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Pycnidia forming on OA. H. Pycnidia. I. Section of pycnidial wall. J. Conidia. Scale bars: G = 300 μm; H = 30 μm; I–J = 5 μm.

Etymology: Epithet derived from the location of origin, Suiyang County in Guizhou, China.

Conidiomata pycnidial, solitary, sometimes aggregated, globose to irregular, brown, covered by some hyphal outgrowths, superficial or semi-immersed, ostiolate, (65–)90–240 × 55–180 μm. Ostiole single, slightly papillate or non-papillate. Pycnidial wall pseudoparenchymatous, composed of oblong to isodiametric cells, 2–4 layers, 15–36.5 μm thick, outer wall 2-layers pigmented. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 4–4.5 × 3–4 μm. Conidia ellipsoidal to oblong, smooth- and thin-walled, hyaline, aseptate, 3.5–7 × 2–3 μm, with indistinct guttules. Conidial matrix cream.

Culture characteristics: Colonies on OA, 52–55 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, sparsely, white to buff; reverse concolourous. Colonies on MEA 59–64 mm diam after 7 d, margin regular, floccose, pale grey to greenish olivaceous; reverse white to yellowish green. Colonies on PDA, 57–61 mm diam after 7 d, margin regular, floccose, white to pale greyish brown; reverse white to hazel. NaOH spot test: a reddish brown discolouration on MEA.

Specimens examined: China, Guizhou, Zunyi, Shuanghe Cave National Geopark, air, 8 May 2015, Z.F. Zhang (holotype HMAS 247158, dried culture, ex-holotype living culture CGMCC 3.18352 = LC 7439); ibid. LC 8144.

Notes: Didymella suiyangensis formed a distinct clade sister to D. bellidis and D. segeticola (Fig. 1), with respectively 18 bp and 19 bp differences in four loci from the latter two species. However, D. suiyangensis is differentiated from D. bellidis and D. segeticola in producing narrower conidiogenous cells (4–4.5 × 3–4 μm vs. 3–6 × 4–8 μm and 5–6.5 × 4–5.5 μm), and the number of ostioles (1 vs. 1–5 and 1–2, respectively). Moreover, the NaOH reactions on MEA showed a reddish brown discolouration on D. suiyangensis, but green to red on D. bellidis and negative on D. segeticola (de Gruyter et al. 1993, Chen et al. 2015b).

Epicoccum Link, Mag. Neuesten Entdeck. Gesammten Naturk. Ges. Naturf. Freunde Berlin 7: 32. 1815, emend. Q. Chen & L. Cai, Stud. Mycol. 82: 171. 2015.

Epicoccum camelliae Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818958.

Etymology: Name refers to the host genus from which the holotype was collected, Camellia.

Cultures sterile. Epicoccum camelliae differs from its closest phylogenetic neighbour E. viticis by unique fixed alleles in three loci based on alignments of the separate loci deposited in TreeBASE (S20724): LSU positions: 66(T), 398(T); tub2 positions: 30(T), 258(C); rpb2 positions: 47(C), 95(C), 197(A), 419(C), 554(A).

Specimens examined: China, Jiangxi, Ganzhou, leaves of Camellia sinensis, 7 Sep. 2013, Y. Zhang (holotype HMAS 247159, dried culture, culture ex-holotype CGMCC 3.18343 = LC 4858); ibid. LC4862.

Notes: Epicoccum camelliae is closely related to E. viticis with a high support value in the phylogenetic tree (Fig. 1), and has 10 bp differences in four loci from the latter. Two isolates of this species are both from Camellia sinensis, one as endophyte in healthy leaves and the other as pathogenic fungus from diseased leaves. Both isolates proved to be sterile on the defined media used in this study.

Epicoccum dendrobii Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818964. Fig. 19.

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Fig. 19

Epicoccum dendrobii (CGMCC 3.18359). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G. Sporodochia. H–I. Conidia. Scale bars: G–I = 10 μm.

Etymology: Named after the host plant, Dendrobium.

Leaf spots amphigenous, subcircular, up to 10 mm diam, black (Fig. 7E). Conidiomata sporodochial, aggregated, semi-immersed or superficial, clavate, pale brown. Hyphae septate, frequently branched, 2.5–4.5 μm. Conidia globose, aseptate and smooth when young, later becoming multicellular-phragmosporous, verrucose, subglobose-pyriform, brown, with a basal cell, 11–19 μm diam.

Culture characteristics: Colonies on OA, 58–64 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, dense, white to greyish yellow; reverse white to pale grey, with some purple dots scattered over the colony. Colonies on MEA 65–68 mm diam after 7 d, margin regular, grey, with sparse white aerial mycelia; reverse white to yellow. Colonies on PDA, 34–38 mm diam after 7 d, margin regular, aerial mycelia felty to floccose, flat, white to buff, olivaceous near the centre; reverse pale salmon, hazel to brown near the centre. NaOH test negative.

Specimens examined: China, Guizhou, Xingyi, on leaves of Dendrobium fimbriatum, 4 Jul. 2015, Q. Chen (holotype HMAS 247160, dried culture, ex-holotype living culture CGMCC 3.18359 = LC 8145); ibid. LC 8146.

Notes: Epicoccum dendrobii formed a distinct clade basal to E. nigrum, E. poae and E. layuense (Fig. 1). These species all produce typical epicoccoid conidia (multicellular-phragmosporous, verrucose), with phoma-like conidia only observed in E. nigrum. Epicoccum dendrobii differs in the length of its epicoccoid conidia (11–19 μm) from E. nigrum (15–35 μm; Punithalingam et al. 1972) and E. poae (10–23 μm), and in its NaOH reaction (negative) from E. layuense (a pale reddish brown discolouration on MEA, with a yellowish brown margin).

Epicoccum duchesneae Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818966. Fig. 20.

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Fig. 20

Epicoccum duchesneae (CGMCC 3.18345). A–B. Colony on OA (front and reverse). C–D. Colony on MEA (front and reverse). E–F. Colony on PDA (front and reverse). G–H. Pycnidia. I. Section of pycnidium. J. Section of pycnidial wall. K–M. Conidiogenous cells. N. Conidia. Scale bars: G–I = 40 μm; J, M–N = 10 μm; K–L = 5 μm.

Etymology: Name derived from Duchesnea, the plant genus from which the holotype was collected.

Leaf spots amphigenous, circular to irregular, 2–5 mm diam, yellowish brown, surrounded by a purple border (Fig. 7F). Conidiomata pycnidial, solitary, globose to subglobose, covered with hyphal outgrowths, immersed in agar, ostiolate, (150–)170–270 × (100–)150–230 μm. Ostiole single, sometimes with an elongated, pale brown neck, slightly papillate. Pycnidial wall pseudoparenchymatous, composed of isodiametric cells, 3–5 layers, 13–30 μm thick, outer wall of 2–3 pigmented layers. Conidiogenous cells phialidic, hyaline, smooth, ampulliform to doliiform, 4.5–9.5 × 3.5–7 μm. Conidia ellipsoidal to oblong, smooth- and thin-walled, hyaline, aseptate, 2.5–3.5 × 1.5–2 μm, egutullate or sometimes with 1(–3) small guttules. Conidial matrix whitish to salmon.

Culture characteristics: Colonies on OA, 62–65 mm diam after 7 d, margin regular, covered by floccose aerial mycelia, white to grey, greyish brown near the centre; reverse white to dark brown. Colonies on MEA 24–27 mm diam after 7 d, margin regular, covered by white, sparse floccose aerial mycelia, grey to pale olivaceous; reverse concolourous. Colonies on PDA, 55–60 mm diam after 7 d, margin regular, aerial mycelia covering the whole colony, floccose, white to grey; reverse greenish olivaceous to dark brown. Application of NaOH results in a pale olivaceous discolouration of the agar.

Specimens examined: China, Jiangxi, Ganzhou, on leaves of Duchesnea indica, 12 May 2013, Q. Chen (holotype HMAS 247161, dried culture, ex-holotype living culture CGMCC 3.18345 = LC 5139); ibid. LC 8147.

Notes: Epicoccum duchesneae formed a distinct lineage close to E. huancayense (Fig. 1). Epicoccum duchesneae differs in producing smaller conidia from E. huancayense, 2.5–3.5 × 1.5–2 μm vs. (4–)5–8(–12) × 2.5–4.5 μm (de Gruyter et al. 1998).

Epicoccum hordei Q. Chen, Crous & L. Cai, sp. nov. MycoBank MB818961. Fig. 21.