Talaromyces pseudorugulosus Q.M. Wang, Z.X. Feng & L. Wang, in Cao et al., Fungal Diversity 132: 454 (2025)

Index Fungorum number: IF 844827; MycoBank number: MB 844827; Facesoffungi number: FoF 17094; Figs. 1, 2

Etymology –  the species epithet referring to its similarity with Talaromyces rugulosus.

Holotype – HMAS 351923.

Colony characters – CYA 25 °C, 7d: Colonies moderately deep, margins low, entire; texture velvety; mycelium light yellow; sporulation sparse, conidia en masse grayish green (30B, Kornerup and Wanscher 1978); exudates absent, soluble pigments absent; reserve light yellow. MEA 25 °C, 7d: Colonies moderately deep, dented at centers, margins low, entire; radially sulcate; texture velvety; mycelium yellow and white; sporulation moderately sparse, conidia en masse grayish green (30B); exudates absent, soluble pigments absent; reserve light orange-red. YES 25 °C, 7d: Colonies moderately deep, dented at centers, margins low, entire; texture velvety; mycelium yellow and white; sporulation limited, conidia en masse grayish green (30B); exudates limited, in minute clear droplets, soluble pigments absent; reserve brownish-yellow. OA 25 °C, 7d: Colonies restricted, margins low, entire; texture velvety; mycelium yellow and white; sporulation absent; exudates absent, soluble pigments absent; reverse light yellow. DG18 25 °C, 7d: Colonies restricted, margins low, entire; texture velvety; mycelium white; sporulation moderate, conidia en masse pastel green (26A4); exudates absent, soluble pigments absent; reserve brownish-yellow. CREA 25 °C, 7d: Abundant acid produced.

Micromorphology – conidiophores arising from surface hyphae; stipes 68.7–438 × 1.8–3.5 µm, smooth walled; penicilli biverticillate; metulae 2–5 per verticil, 9–13 × 2.5–3 µm; phialides 4–6 per verticil, acerose to ampulliform, 7–11 × 2–3 µm; conidia ellip soid, 2.5–3.4 × 1.5–2.5 µm, thick-walled. Ascomata not observed.

Material examined – CHINA, Xizang Autonomous Region, soil, Sep 2021, Q.M. Wang, Z.X. Feng, SCDG35t (HMAS 351923, holotype; CGMCC 3.16296, ex-type); Xizang Autonomous Region, soil, Sep 2021, Q.M. Wang, Z.X. Feng, SCDG35tA; Hainan Province, Qionghai Area, Boao Town Yudai Road coconut coast, Tidal flats, Feb 2022, Q.M. Wang, Z.X. Feng, YTHS14-100.

GenBank – HMAS 351923: ON427037 (ITS), ON667682 (BenA), ON703619 (CaM), ON703699 (rpb2); YTHS14- 100: ON427053 (ITS), ON982464 (BenA), ON982465 (CaM), ON703710 (rpb2); SCDG35tA: ON942225 (ITS), ON961790 (BenA), ON961797 (CaM), ON961801 (rpb2).

Notes – Talaromyces pseudorugulosus phylogenetically related to T. acaricola (Fig. 2). It is characterized by slow growth and colonies with yellowish mycelium and abundant acid production on CREA. In the multigene phylogeny, it is closely related to T. acaricola. But T. acaricola bears biverticillate and irregular penicilli and fusiform conidia.

Figure 1 – Talaromyces pseudorugulosus (CGMCC 3.16296, ex-type). a Colonies from left to right (top row) CYA, MEA, YES, and OA; (bottom row) CYA reverse, MEA reverse, DG18 and CREA. b–e Conidiophores. f–g Conidia. Scale bar = 10 µm.

Figure 2 – Maximum Likelihood phylogenetic tree inferred using the combined sequences of ITS, BenA, CaM and rpb2 depicting the phylogenetic positions of new taxa within section Islandici of Talaromyces. Bootstrap percentages over 50% from 1000 bootstrap replicates are shown on the major branches. Bar = 0.05 substitutions per nucleotide position. The new taxa are in red.