Bisifusarium namibense K. Zhang, Yilmaz & Crous 2025, sp. nov.

Bisifusarium namibense K. Zhang, Yilmaz & Crous, sp. nov. MB 858741. Fig. 9. Etymology: Name refers to the fact that it was isolated from soil collected in the Namib desert. Sporodochia formed on SNA and on CLA, giving rise to a creamy conidial mass. Sporodochial conidiophores apically branched, consisting of primary and secondary branches giving rise to 1–2 conidiogenous cells, 20–50 × 3–4 µm. Sporodochial phialides monophialidic, ampulliform to ellipsoid, 10–15 × 3.5–4 µm, with a tubular collarette, 1–3 µm tall, 2 µm diam. Sporodochial macroconidia falcate, gently dorsiventrally curved, with blunt apical cell and blunt basal cell, or poorly developed foot-like basal cell which is rarely present; medianly 1-septate, (14–)15–17(–18) × 3(–3.5) µm. Microconidia mostly 0(–1)-septate, typically ellipsoidal, straight or curved, formed on PDA substrate or in aerial hyphae, 7.5–9.5 × 3–3.5 µm. Chlamydospores intercalary, solitary or in short chains, globose to ellipsoid, 5–10 µm diam. Culture characteristics: Colonies in the dark for 7 d at 25 °C: on OA reaching 7–8 cm diam., flat, aerial mycelium sparse, colony margin entire, surface and reverse pale luteous. Colonies on PDA 6–7 cm diam., raised, aerial mycelium dense, colony margin erose, surface and reverse dirty white. Colonies on SNA reaching 3–4 cm diam., flat, aerial mycelium scant, colony margin erose, surface and reverse cream; odour absent. Typus: Namibia, Gobabeb, desert soil, Nov. 2019, N. Yilmaz (holotype CBS H-25454, culture ex-type CBS 153393 = DTO 484-E6). Additional materials examined: Namibia, Gobabeb, desert soil, Nov. 2019, N. Yilmaz, cultures CBS 153394 = DTO 484- E8, CBS 153395 = DTO 484-E9, CBS 153537 = DTO 484-E7. Note: Bisifusarium namibense is morphologically similar to B. lunatum (0–1-septate macroconidia, (11.5–)18–22.5(– 26.5) × (2.5–)3–3.5(–4) µm; Shroers et al. 2009), but can be distinguished based on its smaller macroconidia, and DNA sequence data.