Diabolocovidia claustri Crous, sp. nov.

MycoBank number: MB 835402; Index Fungorum number: IF 835402; Facesoffungi number: FoF;

Etymology. Name refers to the closure or lockdown experienced in many countries during the COVID-19 pandemic.

Mycelium consisting of branched, septate, hyaline to pale brown, smooth to finely roughened, 2 – 3 µm diam hyphae. Conidiophores solitary, erect, flexuous, mostly reduced to a terminal conidiogenous cell. Conidiogenous cells pale brown, smooth, subcylindrical to slightly clavate, 8 –10 × 3 – 4 µm, proliferating via single apical blastic locus, and remaining attached to acro- petal chain of conidia that remain attached to one another via narrow isthmus. Conidia brown, thin-walled, smooth, guttulate, granular, ellipsoid to obovoid, (7–)8 – 9(–11) × (4 –)5 – 6(–7) µm; conidia remaining attached in chains of 8 –12 propagules, dis- articulating at maturity into single propagules or shorter chains.

Culture characteristics — Colonies flat, spreading, with sparse to moderate aerial mycelium and feathery, lobate mar- gin, reaching 30 mm diam after 2 wk at 25 °C. On MEA surface and reverse cinnamon. On PDA surface and reverse hazel to brown vinaceous. On OA surface hazel.

Typus. USA, Florida, Gainesville, on leaves of Serenoa repens (Arecaceae), 28 Feb. 2018, M.J. Wingfield, HPC 2792 (holotype CBS H-24353, culture ex-type CPC 37593 = CBS 146630; ITS and LSU sequences GenBank MT373367.1 and MT373350.1).

NotesDiabolocovidia is reminiscent of genera such as Ampullifera (but conidiophores different and hyphopodia pre- sent) and Junctospora (but conidiophores sparingly branched, subhyaline; Seifert et al. 2011). Phylogenetically, it is allied to Vamsapriya, which is characterised by having brown, synnematous conidiophores, mono- to polytretic conidiogenous cells, and dark brown, septate conidia arranged in acropetal chains (Dai et al. 2014). Based on these differences, Diabolocovidia is herewith introduced as a new genus.

Based on a megablast search of NCBIs GenBank nucleotide database, the closest hits using the ITS sequence had highest similarity to Vamsapriya khunkonensis (voucher MFLU 13-0367, GenBank NR_154499.1; Identities = 427/464 (92 %), 5 gaps (1 %)), Didymobotryum rigidum (strain JCM 8837, GenBank LC228650.1; Identities = 517/561 (92 %), 7 gaps (1 %)), and Vamsapriya bambusicola (voucher MFLU 13-0368, GenBank NR_154500.1; Identities = 533/605 (88 %), 37 gaps (6 %)). Closest hits using the LSU sequence are Vamsapriya bambusicola (strain MFLUCC 11-0477, GenBank NG_067527.1; Identities = 849/864 (98 %), no gaps), Fasciatispora petrakii (strain HKUCC 207, GenBank AY083828.1; Identities = 832/848 (98 %), 1 gap (0 %)), and Vamsapriya indica (strain MFLUCC 12-0544, GenBank KM462840.1; Identities = 815/831 (98 %), no gaps).