Pseudohumicola glauca Sastoque, Stchigel & Cano 2025

Pseudohumicola glauca (De Bert.) Sastoque, Stchigel & Cano, comb. nov. MycoBank MB 853458. Fig. 9. Basionym: Humicola glauca De Bert., Canad. J. Bot. 54: 2757. 1976. Typus: Italy, nematode-infested soil, 1970, coll. and isol. M. de Bertoldi (lectotype designated here CBS H-7238, MBT 10026348, culture ex-type CBS 462.76 = MUCL 19429 = FMR 19938). On potato carrot agar after 2 wk at 25 °C: Mycelium composed of hyaline, septate, branched, smooth- and thin-walled, 1–2 μm wide hyphae. Conidiophores absent. Conidiogenous cells integrated to the hyphae. Conidia holoblastic, unicellular, solitary, sessile or on short conical denticles or on short side branches (Fig. 9E), less frequently in short chains or forming few-celled clusters (Fig. 9F), or intercalary (holothallic; Fig. 9F), smooth- and thick-walled, covered by a mucilaginous and dark brown substance, becoming verrucose to reticulate when old, pale olivaceous brown to brown, globose, subglobose, oblate, ellipsoid, obovoid, piriform, occasionally ovoid or cylindric, (4–)7–8(–9) × (4–)8–10(–15) μm (Fig. 9E, F). Acremonium-like synasexual morph and sexual morph not observed. Culture characteristics (after 7 d at 25 ° C): Colonies on PCA 30–31 mm diam., flat and circular; margins filamentous and regular; surface chocolate (6F4) at the centre, with a white (6A1) aerial mycelium, margins yellowish white (4A2); soluble pigment absent; reverse dark brown (6F2) at the centre, surrounded by a chocolate (6F4) halo, margins yellowish-white (4A2). Colonies on OA 37–39 mm diam., flat and circular and expansive; margins filamentous and regular; surface dark brown (5F8), with a floccose white (4B1) aerial mycelium at the centre, margins cream (4B3); soluble pigment absent; reverse dark brown (5F8) at the centre, marble-white (5B2) at the margins. Colonies on CMA 31–34 mm diam., flat and circular; margins filamentous and regular; surface dark brown (5F5) at the centre, with a scarce white (5A1) aerial mycelium, margins yellowish white (4A2) to uncoloured; soluble pigment absent; reverse similar in colour than the surface. Colonies on MEA 35–36 mm diam., flat and circular; margins filamentous and regular; surface brown (5E5) with a floccose white (8A1) aerial mycelium at the centre, margins yellowish white (4A2); reverse cream (4A3) but brown (5E4) at the centre. Culture iconography after 2 wk of incubation on PCA, OA, CMA and MEA (Fig. 9A–D, respectively). Minimum, optimum and maximum temperature of growth on PDA after 7 d: 15 °C, 30 °C and 37 °C, respectively. Additional material examined: Spain, Canary Islands, La Palma, Fuencaliente (Los Canarios), isolated from Teneguía volcano soil, 15 Jul. 2008, coll. M. Calduch & A.M. Stchigel, isol. A.P. Sastoque (culture FMR 18982 = CBS 150904). Notes: Humicola glauca CBS 462.76 was placed close to P. semispiralis CBS 723.97 (Fig. 1), and consequently transferred to the genus Pseudohumicola. Pseudohumicola glauca differs from Pseudohumicola semispiralis by lacking a sexual morph and by the size and shape of conidia [globose, subglobose, oblate, ellipsoid, obovoid, piriform, occasionally ovoid or cylindric, (4–)7–8(–9) × (4–)8–10(–15) μm in P. glauca vs globose to oblate, sometimes ovoid, (8.5–)9–11 μm diam. in P. semispiralis] (Udagawa & Cain 1969, Wang et al. 2019b).