Penicillium lentum R. N. Liang & G. Z. Zhao 2025, sp. nov.

Penicillium lentum R. N. Liang & G. Z. Zhao sp. nov. Fig. 5 Infrageneric classification. Subgenus Penicillium, section Brevicompacta, series Tularensia. Etymology. The specific epithet “ lentum ” is derived from lentus (Latin), reflecting the slow growth rate characteristic of this species. Type. China • Beijing, Haidian District, Beijing Forestry University, 40°0'20"N, 116°20'51"E, from indoor dust, 1 February 2024, collected by G. Z. Zhao, B 24 (holotype HMAS 353385, dried culture; culture ex-type CGMCC 3.28596). Colony diameter after 7 d (mm). CYA 7–10; CYA 30 ° C, 37 ° C no growth; MEA 6–9; YES 9–13; DG 18 7–11; CREA 3.5–5. Colony characteristics (7 d). CYA at 25 ° C: Colonies deep, raised at center, margins low, narrow, irregular; mycelium white; texture velutinous, floccose areas present; sporulation moderate to good, conidia antique green (R. Pl. VI); exudate clear; reverse capucine buff (R. Pl. III); soluble pigment absent. MEA at 25 ° C: Colonies deep, raised at center, margins low, narrow, entire; mycelium white; texture velutinous, floccose areas present; sporulation moderate to good, conidia celandine green (R. Pl. XLVII) to deep turtle green (R. Pl. XXXII); exudate clear; reverse light orange-yellow (R. Pl. III); soluble pigment absent. YES at 25 ° C: Colonies deep, radially and concentrically sulcate, raised at center, margins low, narrow, entire; mycelium white; texture velutinous and fasciculate; sporulation good to strong, conidia glaucous-green (R. Pl. XXXIII); exudate absent; reverse cinnamon (R. Pl. XXIX); soluble pigment absent. DG 18 at 25 ° C: Colonies low, plane, margins low, wide, entire; mycelium white; texture velutinous and fasciculate; sporulation good, conidia bluish gray-green (R. Pl. XLII); exudate absent; reverse antimony yellow (R. Pl. XV); soluble pigment absent. CREA at 25 ° C: Weak growth, no acid production. Ehrlich reaction negative. Micromorphology. Conidiophores biverticillate to terverticillate; stipes smooth-walled, 70–236.5 × 2.5–4.5 μm; rami two when present, 6.5–18 × 2–4 μm; metulae divergent, 2–4 per branch / ramus, 4.0–13.0 × 2.5–4.5 μm; phialides ampulliform, 3–8 per metula, 4.5–8.0 × 2–3 μm; conidia broadly ellipsoidal, smooth-walled, 2–3 × 1.5–2.5 μm. Notes. Penicillium lentum belongs to section Brevicompacta and is most closely related to P. tularense (Fig. 1). Penicillium tularense produces light brown to pale tan cleistothecia, which are not found in the new species (Paden 1971). Additionally, P. lentum has broadly ellipsoidal conidia, while P. tularense produces globose to subglobose conidia (Table 3).