Pseudosoloacrosporiella cryptomeriae Crous, sp. nov.

MycoBank number: MB 841785; Index Fungorum number: IF 841785; Facesoffungi number: FoF;

Etymology. Name refers to the host genus Cryptomeria from which it was isolated.

Mycelium consisting of pale brown, smooth, branched, septate, 1.5 – 2 µm diam hyphae. Conidiophores solitary, erect, pale brown, smooth, subcylindrical with apical taper, 0 –1-septate, mostly reduced to conidiogenous cells. Conidiogenous cells 15 – 30 × 3 – 4 µm, with 1– 3 sympodial apical loci with rhexolytic conidiogenesis, leaving minute collarettes on denticulate loci, 0.5 µm diam. Ramoconidia fusoid-ellipsoid, tapering towards both ends, pale brown, smooth, guttulate, 1– 3-septate, 15– 20 × 3 – 4 µm, with 1– 3 apical loci. Conidia in long (–15) unbranched chains, 0 –1-septate, fusoid-ellipsoid, pale brown, smooth, (7–)12 –13(–15) × (2.5 –)3(– 3.5) µm; loci rhexolytic, 0.5 µm diam, with minute marginal frill.

Culture characteristics — Colonies flat, spreading, surface folded, with moderate aerial mycelium and smooth, lobate margin, reaching 8 mm diam after 7 d at 25 °C. On MEA, PDA and OA surface and reverse ochreous.

Typus. NETHERLANDS, Gelderland Province, Wageningen, Belmonte Botanical Garden, on leaves of Cryptomeria japonica (Cupressaceae), 28 July 2020, P.W. Crous, HPC 3301 (holotype CBS H-24883, culture ex-type CPC 39587 = CBS 148441, ITS, LSU and tef1 (first part) sequences GenBank OK664704.1, OK663743.1 and OK651183.1).

Notes — Pseudoacrosporiella is phylogenetically closely related to Soloacrosporiella, but distinct in that it lacks setae, and its conidia do not have thickened and darkened hila, but rather have a characteristic marginal frill (also on conidiogenous loci), which also distinguishes it from Soloacrospora and Neocladophialophora (Castañeda Ruiz et al. 1997, Crous et al. 2014b).

Based on a megablast search of NCBIs GenBank nucleotide database, the closest hits using the ITS sequence had highest similarity to Neocladophialophora quercina (strain CBS 138874, GenBank NR_137948.1; Identities = 497/557 (89 %), 17 gaps (3 %)) and Soloacrosporiella acaciae (strain CBS 139894, GenBank NR_137986.1; Identities = 413/494 (84 %), 38 gaps (7 %)). Closest hits using the LSU sequence are Neocladophi­ alophora quercina (strain CBS 138874, GenBank MH877670.1; Identities = 772/810 (95 %), one gap (0 %)), Soloacrosporiella acaciae (strain CBS 139894, GenBank NG_058164.1; Identities = 761/814 (93 %), two gaps (0 %)), and Neoscolecobasidium agapanthi (strain CPC 28778, GenBank NG_059748.1; Identities = 695/793 (88 %), 14 gaps (1 %)). No significant hits were obtained when the tef1 (first part) sequence was used in blastn and megablast searches.