Caespitomonium euphorbiae Crous, sp. nov.

 MycoBank number: MB 841777; Index Fungorum number: IF 841777; Facesoffungi number: FoF12727;

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

Conidiophores solitary to aggregated, penicillate, branch- ing extensively, aggregating, becoming tuft-like, arising from superficial mycelium, subcylindrical, hyaline, smooth, 40 –100 µm tall, 3 – 4 µm diam at base. Stipe hyaline, smooth, subcy- lindrical, septate, 15 – 30 × 3 – 4 µm. Primary and secondary branches subcylindrical, hyaline, smooth, aseptate, 8 –12 × 2.5 – 3 µm. Conidiogenous cells phialidic, hyaline, smooth, terminal and intercalary, subcylindrical to narrowly ampulliform, with apical taper, 12 – 22 × 2.5 – 3 µm; apex with short, 1–1.5 µm long, non-flared collarette. Conidia in long unbranched chains, aseptate, hyaline, smooth, ellipsoid, apex subobtuse, base with truncate hilum, (5 –)5.5 – 6(– 6.5) × 2.5 – 3 µm.

Culture characteristics — Colonies flat, spreading, surface with concentric zone lines, with sparse to moderate aerial my- celium and smooth, lobate margin, reaching 40 mm diam after 2 wk at 25 °C. On malt extract agar (MEA), potato dextrose agar (PDA) and oatmeal agar (OA) surface and reverse buff.

Typus. NAMIBIA, Walvis Bay, on Euphorbia sp. (Euphorbiaceae), 20 Nov. 2019, P.W. Crous, HPC 3127 (holotype CBS H-24539, culture ex-type CPC 39083 = CBS 147075, ITS, LSU, actA, rpb2, tef1 (second part) and tub2 sequences GenBank OK664698.1, OK663737.1, OK651122.1, OK651157.1, OK651197.1 and OK651201.1).