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

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

Fig. 5 View Figure 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 View Materials , dried culture; culture ex-type CGMCC 3.28596 View Materials ) GoogleMaps .

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 View Figure 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 View Table 3 ).