Nothophaeomoniella ekebergiae Crous, sp. nov.

MycoBank number: MB 839544; Index Fungorum number: IF 839544; Facesoffungi number: FoF;

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

Conidiomata pycnidial, black, globose, 80 –150 µm diam, with central ostiole; wall of 6 – 8 layers of brown textura angularis; occurring as separate conidiomata on SNA and OA, but aggregated, immersed in a continuous black stroma on MEA. Sporulating poorly on OA: conidiophores reduced to conidiogenous cells, ampulliform, lining inner cavity, hyaline to pale brown, smooth, phialidic, 5 – 8 × 2 – 3 µm. Conidia solitary, aseptate, hyaline, smooth, ellipsoid, 3 – 4 × 1.5 – 2 µm.

Culture characteristics — Colonies flat, spreading, surface folded, with sparse aerial mycelium, and even, lobate margins, reaching 10 mm diam. On MEA surface and reverse olivaceous grey, with buff margin; on PDA surface dull green with margin buff, reverse buff; on OA surface dull green with margin buff.

Typus. SOUTH AFRICA, Mpumalanga, Mbombela, Buffelskloof Nature Re- serve, on leaves of Ekebergia pterophylla (Meliaceae), 23 Nov. 2018, P.W. Crous, HPC 3136 (holotype CBS H-24750, culture ex-type CPC 39341 = CBS 147178, ITS, LSU, tef1 (first part) and tub2 sequences GenBank MZ064456.1, MZ064513.1, MZ078237.1 and MZ078278.1).

Notes — Nothophaeomoniella is related to ‘Phaeomoniella’ pinifoliorum, which also represents a genus distinct from Phaeomoniella, typified by P. chlamydospora (Crous & Gams 2000, Crous et al. 2015a). A new genus is thus introduced to accommodate this species, isolated from leaves of Ekebergia pterophylla, and forming a coelomycetous morph in culture. The Phaeomoniellales was recently treated by Kraus et al. (2020).

Based on a megablast search of NCBIs GenBank nucleotide database, the closest hits using the ITS sequence had highest similarity to Vredendaliella oleae (as Phaeomoniellales sp. CS-2020a; strain CBS 146757, GenBank MT791073.1; Identities = 471/498 (95 %), ten gaps (2 %)), Aequabiliella effusa (strain P6, GenBank MK801313.1; Identities = 450/482 (93 %), ten gaps (2 %)) and Aequabiliella palatina (strain JKI- Ap36, GenBank MH999506.1; Identities = 445/482 (92 %), 11 gaps (2 %)). Closest hits using the LSU sequence are Phaeomoniella pinifoliorum (strain CBS 114903, GenBank NG_064185.1; Identities = 838 /882 (95 %), seven gaps (0 %)), Xenocylindrosporium kirstenboschense (strain CBS 125545, GenBank NG_057857.1; Identities = 813 /862 (94 %), eight gaps (0 %)) and Paraphaeoisaria alabamensis (strain CBS 101.77A, GenBank MH872801.1; Identities = 792 /845 (94 %), 13 gaps (1 %)). No significant hits were obtained when the tef1 sequence was used in blastn and megablast searches. Distant hits obtained using the tub2 sequence had highest similarity to Vredendaliella oleae (strain CBS 146757, GenBank MW017334.1; Identities = 275/323 (85 %), two gaps (0 %)), Aequabiliella palatina (strain JKI-Ap36, GenBank MK070469.1; Identities = 247/308 (80 %), 13 gaps (4 %)) and Moristroma palatinum (strain JKI-Au02, GenBank MK070475.1; Identities = 254/319 (80 %), 16 gaps (5 %)).