Paradinemasporium junci Crous & Osieck, sp. nov.
MycoBank number: MB 841835; Index Fungorum number: IF 841835; Facesoffungi number: FoF;
Etymology. Name refers to the host genus Juncus from which it was isolated.
Conidiomata stromatic, acervuloid, 100 – 500 μm diam, mostly solitary on host, to aggregated (PNA), pale brown with luteous mucoid conidial mass, setose; basal stroma of subglobose cells, lateral excipulum absent. Setae interspersed, arising from basal stroma, straight, multi-septate, brown, unbranched, thick-walled, 100 – 250 μm long, 4 – 6 μm wide, fertile at apex, with flared collarette. Conidiophores lining cavity, subcylindrical, hyaline, smooth-walled, branched, septate, 40 – 80 × 3 – 4 μm. Conidio genous cells phialidic, subcylindrical, hyaline to subhyaline, smooth-walled, 15 – 27 × 2.5 – 3.5 μm; apex with flared collarette which is 3–5 μm diam. Conidia (12 –)13 –14 × (2.5 –)3 μm, fusoid to subcylindrical, hyaline, smooth-walled, guttulate, medianly 1-septate, apex with 2 – 3 excentric appendages, 7–10 μm long; base with a single central appendage, 9 –12 μm long.
Culture characteristics — Colonies flat, spreading, with moderate aerial mycelium and even, lobate margin, reaching 50 mm diam after 2 wk at 25 °C. On MEA surface cinnamon to isabelline, reverse isabelline; on PDA surface and reverse cinnamon; on OA surface cinnamon.
Typus. NETHERLANDS, Overijssel Province, Engbertsdijksvenen, near Vriezenveen, 13 m a.s.l., N52°26’53” E06°40’02”, on dead culm of Juncus effusus (Juncaceae), 9 Mar. 2021, E.R. Osieck, HPC 3612 = WI-31/#4227 (holotype CBS H-24856, culture ex-type CPC 41315 = CBS 148317, ITS, LSU and tef1 (second part) sequences GenBank OK664752.1, OK663791.1 and OK651199.1).
Additional material examined. NETHERLANDS, Overijssel Province, Engberts- dijksvenen, near Kloosterhaar, 17 m a.s.l., N52°28’57”, E06°40’02”, on dead culm of Juncus effusus, 9 Mar. 2021, E.R. Osieck, HPC 3611 = WI-30/#4226, culture CPC 41343, ITS and LSU sequences GenBank OK664754.1 and OK663793.1; Utrecht Province, Utrecht, Leersum, Leersumse Plassen, 8 m a.s.l., N52°02’28” E05°26’26”, on dead culm of Juncus effusus, 26 Jan. 2021, E.R. Osieck, HPC 3584 = WI-16/#4212, culture CPC 41003, ITS, LSU and tef1 (second part) sequences GenBank OK664753.1, OK663792.1 and OK651200.1.
Notes — Paradinemasporium forms a well-defined distinct clade related to Pseudodinemasporium and Neopseudolach nella (Crous et al. 2012, Hashimoto et al. 2015). It most closely resembles Dinemasporium in conidial morphology and append- ages, but also Neopseudolachnella in having sporodochia that lack a well-defined lateral excipulum. Paradinemasporium junci resembles D. strigosum (common on monocotyledons) but the latter has shorter conidia and a single appendage at each end (Duan et al. 2007).
Based on a megablast search of NCBIs GenBank nucleotide database, the closest hits using the ITS sequence of CPC 41315 had highest similarity to Neopseudolachnella uniseptata (voucher HHUF 29728, GenBank NR_154225.1; Identities = 402/437 (92 %), eight gaps (1 %)), Neopseudolachnella magn ispora (voucher HHUF 29977, GenBank NR_154224.1; Identi- ties = 426/469 (91 %), 16 gaps (3 %)), and Pseudolachnella complanata (voucher HHUF 28282, GenBank NR_154278.1; Identities = 333/368 (90 %), 12 gaps (3 %)). The ITS sequence of CPC 41315 differs two gaps (462/464 nucleotides, including two gaps) from CPC 41003 and two nucleotides and one gap from CPC 41343 (464/467 nucleotides, including one gap). Closest hits using the LSU sequence of CPC 41315 are Neopseudolachnella magnispora (voucher HHUF 29977, GenBank NG_059405.1; Identities = 760/774 (98 %), two gaps (0 %)), Neopseudolachnella uniseptata (voucher HHUF 29728, GenBank NG_059406.1; Identities = 759/773 (98 %), one gap (0 %)), and Pseudolachnella fusiformis (voucher HHUF 29725, GenBank AB934056.1; Identities = 758/773 (98 %), two gaps (0 %)). The LSU sequence of CPC 41315 is identical to those of CPC 41003 and CPC 41343 (both 773/773 nucleotides, no gaps). Closest hits using the tef1 (second part) sequence of CPC 41315 had highest similarity to Dictyochaeta cangs hanensis (voucher MFLU 18-1614, GenBank MN194083.1; Identities = 802/845 (95 %), no gaps), Neopseudolachnella magnispora (voucher HHUF 29977, GenBank AB934092.1; Identities = 801/852 (94 %), no gaps), and Dictyochaeta submersa (voucher MFLU 18-2321, GenBank MN194082.1; Identities = 764/814 (94 %), no gaps). The tef1 sequence of CPC 41315 differs one nucleotide (810/811 nucleotides, no gaps) from CPC 41003.