Referring to Ausona (Osona), the region of Catalonia where the fungus was collected.

Spain, Catalonia, Osona, Guilleries-Savassona Natural Park, Malafogassa, Major Stream, from sediments, Nov. 2018, E. Carvalho & J. Gené (holotypeCBS H-24781, cultures ex-type CBS 148237 = FMR 16948).

SubgenusAspergilloides, sectionLanata-Divaricata, series Dalearum.

Mycelium superficial and immersed, composed of septate, smooth-walled, hyaline hyphae, 2–3 μm wide. Conidiophores monoverticillate and divaricate, minor proportion biverticillate; stipes smooth-walled, 20–120 × 2–2.5 μm; metulae slightly appressed to divergent, mostly 2, occasionally 3 per stipe, 10–18 × 2–3 μm, occasionally a solitary phialide borne on the same level as metulae; phialides 2–5 per stipe/metula, ampulliform to cylindrical, 9–12 × 2–3 μm; conidia smooth-walled, globose to subglobose, 2–3 × 2–3 μm.

Colonies on CYA, 58–59 mm diam., slightly radially and concentrically sulcate, velvety to floccose, whitish (5A1), margins regular and slightly fimbriate, sporulation absent to sparse, when present conidial masses brownish gray (6C2); reverse grayish yellow (4B4); little production of exudates hyaline, soluble pigment absent. On MEA, 61–62 mm diam., slightly raised, floccose, white (3A1), margins fimbriate, sporulation absent to sparse, conidial masses brownish gray (5E3); reverse light yellow (4A4); exudate absent, soluble pigment absent. On YES, 67–71 mm diam., slightly raised, radially sulcate, randomly furrowed as well, velvety to floccose, dull yellow (3B3) at center and white (3B1) towards periphery, margins slightly fimbriate, sporulation absent to sparse, conidial masses grayish to dull green (25C4–5C); reverse brownish yellow (5C8), exudates and soluble pigment absent. On OA, 63–65 mm diam., slightly raised, white (3A1) with gray (3E1) to olive (3F3) areas, velvety, margins slightly fimbriate, sporulation abundant, conidial masses grayish to dull green (25C5–D5); reverse grayish-yellow (3B5); exudates and soluble pigment absent. On DG18, 10–12 mm diam., randomly furrowed at the center, radially sulcate towards periphery, velvety, yellowish gray (2B2), margins entire, sporulation absent to sparse, conidial masses grayish to dull green (25C4–5C); reverse grayish yellow (2C3); exudates and soluble pigment absent. On CREA, 61–63 mm diam., slightly raised, floccose, gray (4B1) at center to yellowish gray (4B2) and white (4A1) towards periphery, margins slightly fimbriate, sporulation abundant, conidial masses brownish gray (6C2); reverse vivid yellow (3A8); exudates absent, acid production strong.

5 °C 3–2, 15 °C 41–43, 20 °C 46–48, 30 °C 56–57, 35 °C 50–51, 37 °C 38–39, 40 °C no growth.

Spain.

Penicilliumausonanum formed a phylogenetically supported group together with P.amphipolaria and P.viridissimum in series Dalearum (Fig. 6). These are two species recently described, the former from soil in Antarctica and Canada, and the latter from acidic and forest soil from China (Visagie et al. 2016a, Diao et al. 2019). The new species can be morphologically differentiated from them by its equal proportion of monoverticillate and divaricate conidiophores, which are mostly with a complex branching pattern in P.amphipolaria (biverticillate and divaricate) (Visagie et al. 2016a), and mono- to terverticillate in P.viridissimum (Diao et al. 2019). Both P.amphipolaria (6.5–10 µm) and P.viridissimum (6.5–10 µm) have slightly shorter phialides than P.ausonanum (9–12 µm). Also, P.amphipolaria (240–460 µm) and P.viridissimum (40–125 µm) have longer stipes (Visagie et al. 2016a, Diao et al. 2019) in comparison to those of P.ausonanum (20–120 µm). Furthermore, the three species also differed in acid production on CREA, which is strong in P.ausonanum, moderate in P.amphipolaria and absent in the neighboring species P.viridissimum.