Cadophora dextrinospora (Korf) Koukol & Maciá-Vicente, comb. nov.
Mycobank: MB 834822
≡ Mollisia dextrinospora Korf, Mycotaxon 10(2): 462 (1980)
Cadophora constrictospora Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 5.
Mycobank: MB 834823
Etymology – Named after the production of constricted conidia.
Description in culture – Colonies on MEA reaching 28–30 mm after 10 days, on PDA and CMA reaching 27–28 mm and 17–18 mm, respectively. Mycelium septate, hyphae subhyaline to pale brown, forming fascicles up to 18 µm in diam., hyphae 2–4 µm in diam. Conidiophores pale brown, straight, unbranched, producing terminal or intercalary fascicles of phialides, rarely absent. Conidiogenous cells phialidic, pale brown, smooth, lanceolate, with distinct collarette up to 3.5 μm long, (8.5)10–14.5(17.5) µm long and 2–4 µm wide. Conidia of two types. Primary conidia hyaline, ellipsoid to narrowly ellipsoid, smooth, nonseptate, with distinct projection on the basis, forming compact heads on the top of phialides, 4–6.5 µm long and 2–2.5 µm wide, the mean conidium length/width ratio 2.3:1. In older cultures, secondary conidia that are pyriform, spathulate to ossiform with distinct constrictions in the middle are formed. They are 6.5–10(12.5) μm long and 3–5 μm wide, the mean conidium length/width ratio 2:1.
Type. Bulgaria, Nepraznentsi, 42.67 N 022.84 E, 740 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 14 May 2013, col. by T. Ali and S. Ploch, isol. by K. Glynou, FR 0255157 (ex-type culture: P1751 = CBS 146371; GenBank accessions: ITS = KT269023, LSU = MN339369, tef1-α = MN325874, rpb2 = MN367280).
Note: The newly described species is distinct in producing large pyriform conidia with distinct constriction in more than 30-day-old cultures. These secondary conidia do not seem to have distinct origin, so that we assume that they are produced by ageing phialides.
Cadophora echinata Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 6.
Mycobank: MB 834828
Etymology – Named after the production of frequently conidia having echinate appearance.
Description in culture – Colonies on MEA reaching 15 mm after 10 days, on PDA and CMA reaching 14 – 16 mm and 15 – 16 mm, respectively. Mycelium septate, hyphae hyaline to dark brown, rarely forming coils up to 38 µm in diam., hyphae 2–3 µm in diam. Conidiophores not developed. Conidiogenous cells integrated, terminal, holoblastic, monoblastic, smooth, cylindrical, up to 3–5 µm wide. Conidia holoblastic complex, originating as chains of fusiform, oval to almost globose cells strongly constricted at the septa, pale brown and becoming darker towards the center, later branching repeatedly and forming compact tuft-like bodies up to 150 μm in diam., individual cells 5.5–9 µm long and 5–9 µm wide.
Type. Spain, Puebla de Don Fadrique, 38.05 N 002.54 W, 1,612 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 2 May 2013, col. by J.G. Maciá-Vicente, isol. by J.G. Maciá-Vicente, FR 0255199 (ex-type culture: P6045 = CBS 146383; GenBank accessions: ITS = KT270239, LSU = MN339428, tef1-α = MN325932, rpb2 = MN367267).
Additional material. Croatia, Gospić, 44.46 N 015.40 E, 755 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 4 May 2013, col. by T. Ali, isol. by K. Glynou, FR 0255154 (culture: P1518; GenBank accessions: ITS = KT268812, LSU = MN339364, tef1-α = MN325869, rpb2 = MN367234). Bulgaria, Divlya, 42.57 N 022.69 E, 685 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 14 May 2013, col. by T. Ali and S. Ploch, isol. by K. Glynou, FR 0255159 (culture: P1823; GenBank accessions: ITS = KT269095, LSU = MN339371, tef1-α = MN325876, rpb2 = MN367281). Bulgaria, Divlya, 42.57 N 022.69 E, 685 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 14 May 2013, col. by T. Ali and S. Ploch, isol. by K. Glynou, FR 0255182 (cultures: P2323; GenBank accessions: ITS = KT269559, LSU = MN339393, tef1-α = MN325897). Spain, Puebla de Don Fadrique, 38.05 N 002.54 W, 1612 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 2 May 2013, col. by J.G. Maciá-Vicente, isol. by J.G. Maciá-Vicente, FR 0255200 (culture: P6077; GenBank accessions: ITS = KT270270, LSU = MN339429, tef1-α = MN325933, rpb2 = MN367268).
Note: For comments on C. echinata see the note at C. gamsii.
Cadophora fascicularis Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 7.
Mycobank: MB 834824
Etymology – Named after the production of ramoconidia in apical fascicles.
Description in culture – Colonies on MEA reaching 17–18 mm after 10 days, on PDA and CMA reaching 16–17 mm and 14–15 mm, respectively. Mycelium septate, hyphae hyaline to dark brown, frequently forming coils up to 50 µm in diam., hyphae 2–2.5 µm in diam. Conidiophores growing from vegetative hyphae or hyphal coils, straight, smooth, consisting of 1–2 cells terminated by a conidiogenous cell, up to 50 µm long and 3–4 µm wide, frequently reduced to the conidiogenous cell. Conidiogenous cells holoblastic, polyblastic, smooth, cylindrical, cuneiform to almost club shaped with several loci at the apex, (11)12.5–18(20.5) µm long and up to 3–5 µm wide in the upper part. Ramoconidia holoblastic 0(-1) septate, pale brown to hyaline, sometimes paler towards the apex, usually forming fascicles on the top of the conidiogenous cell, smooth, straight to slightly curved, subcylindrical to fusiform, not constricted at the septum, (6.5)10.5–16(20) µm long and 2.5–4 µm wide. Conidia hyaline, smooth, elongated lemon shaped to fusiform with slight constriction in the middle, forming short chains, (6.5)8–11(15) µm long and 2–3 µm wide, the mean conidium length/width ratio 3.5:1.
Type. Germany, Darstadt, 49.68 N, 010.00 E, 278 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 6 June 2013, col. by K. Glynou and J.G. Maciá-Vicente, isol. by K. Glynou, FR 0255219 (ex-type culture: P2794 = CBS 146382; GenBank accessions: ITS = KT269992, LSU = MN339414, tef1-α = MN325918).
Note: Cadophora fascicularis differs from most Cadophora species by a lack of phialidic conidiogenous cells. It is morphologically somehow comparable to C. antarctica that also produces chains of ramoconidia and conidia on holoblastic conidiogenous cells. However, C. fascicularis has well developed conidiophores, ramoconidia, and conidia are more elongated than in C. antarctica.
Cadophora ferruginea Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 8.
Mycobank: MB 834826
Etymology – Named after the production of reddish globules and mycelium.
Description in culture – Colonies on MEA reaching 18–20 mm after 10 days, on PDA and CMA reaching 18–19 mm and 16–22 mm, respectively. Mycelium septate, hyphae subhyaline to reddish, forming fascicles up to 15 µm in diam., hyphae 2–4 µm in diam. Conidiophores hyaline, straight, branched and producing terminal fascicle of phialides, rarely absent. Conidiogenous cells phialidic, hyaline, smooth, with distinct collarette (that may disappear at older phialides), 6–10 µm long and 2–3 µm wide. Conidia hyaline, ellipsoid, smooth, nonseptate, forming compact heads on the top of phialides 3–5 µm long and 1.5–2.5 µm wide, the mean conidium length/width ratio 1.8:1.
Type. Spain, Puebla de Don Fadrique, 38.04 N 002.48 W, 1,630 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 2 May 2013, col. by J.G. Maciá-Vicente, isol. by J.G. Maciá-Vicente, FR 0255144 (ex-type culture: P1323 = CBS 146363; GenBank accessions: ITS = KT268618, LSU = MN339356, tef1-α = MN325861).
Note: Cadophora ferruginea belongs among other phialidic members of this genus, but produces phialides that are generally smaller.
Cadophora gamsii Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 9.
Mycobank: MB 834825
Etymology – Named after Walter Gams (1934-2017) who contributed significantly to the study of the genera Cadophora and Phialophora.
Description in culture – Colonies on MEA reaching 12–16 mm after 10 days, on PDA and CMA reaching 11 mm and 12–13 mm, respectively. Mycelium septate, hyphae hyaline to pale brown, hyphae 1.5–2.5 µm wide. Conidiophores not developed. Conidiogenous cells integrated, terminal, holoblastic, monoblastic, smooth, cylindrical, up to 2.5–5 µm wide. Conidia pale brown rather thin walled to dark brown, thick walled, smooth, mostly nonseptate (rarely 1-septate), rather variable in shape, from globose to pyriform, spathulate, fusiform, with distinct constriction in the middle when elongated, forming long chains that are rarely branched. Thin walled elongated conidia (10)14–20(22.5) µm long and 3.5–5.5 µm wide (1-septate up to 20 µm long), the mean conidium length/width ratio 3.9:1, thick walled conidia 7–14.5(18.5) µm long and 5–9 µm wide, the mean conidium length/width ratio 1.7:1.
Type. France, Malbrans, 47.11 N 006.07 E, 543 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 4 May 2013, col. by A.K. Buch and X. Xia, isol. by K. Glynou, FR 0255184 (ex-type culture: P2437 = CBS 146379; GenBank accessions: ITS = KT269668, tef1-α = MN325899, rpb2 = MN367272).
Additional material. France, Malbrans, 47.11 N 006.07 E, 543 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 4 May 2013, col. by A.K. Buch and X. Xia, isol. by K. Glynou (culture: P2440 = CBS 146379; GenBank accessions: ITS = KT269671, LSU = MN339395, tef1-α = MN325900, rpb2 = MN367251).
Note: Cadophora gamsii produces long chains of conidia of variable shapes similarly to C. echinata, where these chains branch and may form large sclerotia-like bodies. However, these structures may be also interpreted as inflated hyphal segments (chlamydospores). At C. orchidicola, they are formed together with regular conidia. Supposedly, these structures obviously do not disperse on long distances, but rather survive in nearby distance and may have dormant function similar to microsclerotia of dothidealean fungi (Tsuneda et al. 2001).
Cadophora cf. interclivum – Figs. 1, 10.
Description in culture – Colonies on MEA reaching 16–17 mm after 10 days, on PDA and CMA reaching 17–18 mm and 17–18 mm, respectively. Mycelium septate, hyphae hyaline to dark brown, frequently forming coils, hyphae 22.5 µm in diam. Conidiophores straight, bearing single or multiple phialides arranged in intercalary or terminal fascicles. Conidiogenous cells phialidic, slightly darker, 6–10 µm long and up to 2–3 µm wide in the upper part terminated by a collarette 2–3.5 µm long. Conidia ellipsoid to ovate with slightly prominent basis, hyaline, with smooth wall, 3–4.5 µm long and 2–3 µm wide, forming clusters but not slimy heads, the mean conidium length/width ratio 1.4:1.
Specimens examined. Germany, Darstadt, 49.68 N 010.00 E, 278 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 6 June 2013, col. by K. Glynou and J.G. Maciá-Vicente, isol. by K. Glynou, FR 0255220 (culture: P2973; GenBank accessions: ITS = KT270169, LSU = MN339425, tef1-α = MN325929, rpb2 = MN367291). Spain, Puebla de Don Fadrique, 38.04 N 002.48 W, 1630 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 2 May 2013, col. by J.G. Maciá-Vicente, isol. by K. Glynou, FR 0255149 (culture: P1396; GenBank accessions: ITS = KT268691, LSU = MN339360, tef1-α = MN325865, rpb2 = MN367278). Germany, Darstadt, 49.68 N 010.00 E, 278 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 6 June 2013, col. by K. Glynou and J.G. Maciá-Vicente, isol. by K. Glynou (culture: P2816; GenBank accessions: ITS = KT270014, LSU = MN339416, tef1-α = MN325920, rpb2 = MN367264).
Note: In total, 25 strains clustered with three sequences of C. interclivum (including its ex-type strain). Both phenotypic and molecular characteristics were difficult to interpret in concordance with the description of C. interclivum by Walsh et al. (2018). Our strains produced slightly darker Phialocephala-like phialides with distinct wide open collarettes at the tip of straight conidiophores (Fig. 9), i.e. different from cylindrical conidiogenous cells with cylindrical collarettes and conidia aggregated in slimy heads of C. interclivum (Walsh et al. 2018). In analyses of individual genetic loci, only sequence data of the intron in the tef1-α gene enabled to distinguish two clades referring to C. interclivum and C. meredithiae with medium support (PP = 0.87, data not shown). In another analysis, the strains were mixed and no clades were clearly delimited. A similar phenomenon was recorded by Walsh et al. (2018), who found two well supported lineages only when analyzing sequences of genes coding the RNA polymerase II largest subunit (rpb1) and β-tubulin. Unfortunately, we did not amplify these markers. Obviously, the lineage C. interclivum/C. meredithiae contains multiple, hitherto unrecognized root colonizing species, and commonly used markers, such as ITS or rpb2, have limited ability to distinguish them.
Cadophora obovata Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 11.
Mycobank: MB 834827
Etymology – Named after the obovate shape of conidia.
Description in culture – Colonies on MEA reaching 27–30 mm after 10 days, on PDA and CMA reaching 22–25 mm and 15 mm, respectively. Mycelium septate, hyphae hyaline to dark brown, frequently forming coils or hyphal fascicles up to 15 µm thick, hyphae 1.5–2.5 µm in diam. Conidiophores absent. Conidiogenous cells holoblastic, monoblastic, obconical, 17–22 µm long and up to 2–3 µm wide in the upper part terminated by a collarette 2–3.5 µm long. Conidia obovate, pale grey-brown, with smooth wall, 6–8(9.5) µm long and 3.5–6 µm wide, the mean conidium length/width ratio 1.5:1.
Type. Germany, Ettringen, 50.37 N 007.22 E, 504 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 9 May 2013, col. by M. Thines, isol. by K. Glynou, FR 0255171 (ex-type culture: P1963 = CBS 146374; GenBank accessions: ITS = KT269230, LSU = MN339384, tef1-α = MN325888, rpb2 = MN367298).
Additional material. France, Saint-Georges-Armont, 47.41 N 006.56 E, 285 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 19 April 2013, col. by J.G. Maciá-Vicente, isol. by J.G. Maciá-Vicente, FR 0255142 (culture: P1101 = CBS 146359; GenBank accessions: ITS = KT268419, LSU = MN339352, tef1-α = MN325858, rpb2 = MN367275). Germany, Ettringen, 50.37 N 007.22 E, 504 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 9 May 2013, col. by M. Thines, isol. by K. Glynou, FR 0255174 (culture: P1978; GenBank accessions: ITS = KT269245, LSU = MN339386, tef1-α = MN325890). Germany, Ettringen, 50.37 N 007.22 E, 504 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 9 May 2013, col. by M. Thines, isol. by K. Glynou, FR 0255176 (culture: P1992; GenBank accessions: ITS = KT269259).
Note: The newly described species is distinct from other Cadophora species by having a putatively monoblastic conidiogenous cell. Although the cell resembles a phialide in having a basal swelling of the conidiogenous cell and an irregular collarette-like structure, no subsequent enteroblastic conidiogenesis typical for phialides was observed. Giving its position in the phylogeny, this type of conidiogenous cell seems to represent a retrogression of enteroblastic phialidic conidiogenesis.
Cadophora cf. orchidicola – Figs. 1, 12.
Description in culture – Colonies on MEA reaching 30 mm after 10 days, on PDA and CMA reaching 32–33 mm and 29–30 mm, respectively. Mycelium septate, hyphae subhyaline to dark brown, smooth to verrucose, occasionally forming coils and chains of inflated hyphal segments, rarely branched, up to 6 μm thick, hyphae 1.5–2.5 µm in diam. Conidiophores straight or flexuous, hyaline, branched or unbranched, bearing single conidiogenous cells intercalary or multiple arranged in terminal fascicles. Conidiogenous cells cylindrical, slightly conical or inflated in lower part, presumably enteroblastic, but without apparent collarette, 6–9.5(12) µm long and up to 2.5–5 µm wide. Conidia produced sympodially, ellipsoid, hyaline, with smooth wall, 3–5 µm long and 1.5–2.5 µm wide, forming clusters of 2–4 on the top of the conidiogenous cell, the mean conidium length/width ratio 1.9:1.
Specimens examined. Bulgaria, Begunovtsi, 42.70 N 022.83 E, 770 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 14 May 2013, col. by T. Ali and S. Ploch, isol. by K. Glynou, FR 0255161 (culture: P1854 = CBS 146372; GenBank accessions: ITS = KT269125, LSU = MN339373, tef1-α = MN325878, rpb2 = MN367238).
Note: The identification of this clade formed by 23 isolates sequenced in this study is only tentative due to ambiguous evidence from phenotypic and molecular data. Currently, C. orchidicola is not represented by any ex-type sequence, is neither epitypified, and the GenBank database contains more than 380 sequences of Cadophora/Leptodontidium orchidicola (search 11 January 2020). BLAST searches performed with representative sequences from this clade indicated multiple matches with similarities of 94.5–99.5 %, indicating substantial inconsistency in species delimitation. Without a reliable sequence as reference, a representative strain of this clade intensively sporulating in culture (P1854) was studied morphologically. The strain P1854 was markedly similar to the description of C. orchidicola. This species originally described from roots of the orchid Calypso bulbosa (L.) Oakes was characterized as producing “slightly swollen conidiogenous cells” and “terminal conidia produced sympodially” without apparent scars (Currah et al. 1987). Our observations confirmed phialide-like conidiogenous cells, but without distinct collarette. i.e. we were not able to identify the exact mode of conidiogenesis. Also the dimensions of conidia were almost identical to those provided by Currah et al. (1987), i.e., 3-5(7) × 1-3 µm.
Cadophora variabilis Koukol & Maciá-Vicente, sp. nov. – Figs. 1, 13.
Mycobank: MB 834829
Etymology – Named after the production of conidia of variable shapes.
Description in culture – Colonies on MEA reaching 9–10 mm after 10 days, on PDA and CMA reaching 10–11 mm and 9–10 mm, respectively. Mycelium septate, hyphae hyaline to dark brown, rarely forming coils up to 55 µm in diam., hyphae 2–3 µm in diam. Conidiophores not developed. Conidiogenous cells integrated, terminal, holoblastic, monoblastic, smooth, cylindrical, up to 3–5 µm wide. Ramoconidia holoblastic nonseptate, pale brown to hyaline, smooth, straight, fusiform, frequently constricted in the middle, (16)18–23.5(25.5) µm long and 5–7.5 µm wide. Conidia pale brown to hyaline, smooth, mostly nonseptate (rarely 1-septate), rather variable in shape, from subglobose to pyriform, obovate or fusiform, with distinct constriction in the middle when elongated, forming chains (rarely with cylindrical connective or aberrant conidium), (8.5)11–21(27) µm long and 5.5–9 µm wide, the mean conidium length/width ratio 2.2:1.
Type. Croatia, Jasenice, 44.24 N, 015.54 E, 760 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 4 May 2013, col. by T. Ali, isol. by K. Glynou, FR 0255203 (ex-type culture: P1176 = CBS 146360; GenBank accessions: ITS = KT268493, LSU = MK539845, tef1-α = MK550890, rpb2 = MN367276).
Additional material. Spain, Puebla de Don Fadrique, 38.04 N, 002.48 W, 1630 m a.s.l., endophytic in roots of M. perfoliatum (Brassicaceae), 2 May 2013, col. by J.G. Maciá-Vicente, isol. by K. Glynou, FR 0255145 (culture: P1331 = CBS 146364; GenBank accessions: ITS = KT268626, LSU = MK539836, tef1-α = MK550891, rpb2 = MN367230).
Note: Cadophora variabilis is highly similar to that of C. antarctica, which also produces chains of ramoconidia and conidia on holoblastic conidiogenous cellsfascicularis. However, ramoconidia and conidia of C. variabilis are larger than those of C. antarctica. Interestingly, these two species are very distant in the phylogeny suggesting that this similar morphology resulted from convergence.