Talaromyces tenuis B.D. Sun, A.J. Chen, Houbraken & Samson, 2020

Sun, Bing-Da, Chen, Amanda J., Houbraken, Jos, Frisvad, Jens C., Wu, Wen-Ping, Wei, Hai-Lei, Zhou, Yu-Guang, Jiang, Xian-Zhi & Samson, Robert A., 2020, New section and species in Talaromyces, MycoKeys 68, pp. 75-113 : 75

Talaromyces tenuis B.D. Sun, A.J. Chen, Houbraken & Samson sp. nov. Fig. 5

Typus.

China, Guizhou, soil, 2014, isolated by X.Z. Jiang, Holotype CBS H-22838, culture ex-holotype CBS 141840 = DTO 340-G9.

ITS barcode.

MN864275. Alternative identification markers: BenA = MN863344, CaM = MN863321, RPB2 = MN863333.

Diagnosis.

Talaromyces tenuis produces hyaline, thin conidiophores, yellow mycelium on MEA and OA, and grows very restrictedly on CYA, YES and DG18.

In.

Talaromyces section Tenues

Colony diam, 7 d (mm).

CYA 7-8; CYA 30 °C 5-8; CYA 37 °C No growth; MEA 18-20; MEA 30 °C 10-11; OA 12-14; YES 9-10; CREA No growth; CYAS No growth; DG18 2-3.

Colony characters.

CYA 25 °C, 7 d: Colonies moderately deep, plane; margins entire; mycelium white; texture floccose; sporulation absent; soluble pigments absent; exudates absent; reverse white. MEA 25 °C, 7 d: Colonies moderately deep, plane; margins entire; mycelium sulphur yellow (15) or ochreous (44); texture floccose; sporulation sparse; conidia en masse white or greyish yellow-green (68); soluble pigments absent; exudates absent; reverse ochreous (44) to umber (9). YES 25 °C, 7 d: Colonies moderately deep, plane; margins entire; mycelium white; texture floccose; sporulation absent; soluble pigments absent; exudates absent; reverse buff (45). DG18 25 °C, 7 d: Colonies moderately deep, plane; margins entire; mycelium white; texture floccose; sporulation absent; soluble pigments absent; exudates absent; reverse white. OA 25 °C, 7 d: Colonies moderately deep, plane; margins entire; mycelium pale luteous (11); texture floccose; sporulation absent; soluble pigments absent; exudates absent; reverse buff (45).

Micromorphology.

Conidiophores monoverticillate or biverticillate, stipes smooth, 80-150 × 2-3 μm; metulae 2-3, divergent, 8-9 × 2-2.5 μm; phialides 2-3, acerose, 8-9.5 × 2-2.5 μm; conidia smooth, globose to subglobose, 2-3 × 2-2.5 μm. Ascomata not observed.

Note.

Talaromyces tenuis is phylogenetically distinct and is basal to species belonging to sections Talaromyces and Helici (Fig. 1 ). In a nine-gene phylogeny, it is sister to sections Purpurei and Trachyspermi ( Houbraken et al. 2020). This species is characterized by hyaline, thin conidiophores, and grows very restrictedly on CYA, YES and DG18; colonies on MEA and OA have prominent yellow mycelia.

Etymology.

Latin, tenuis , refers to its thin conidiophores.

Figures

Figure 1. Concatenated phylogeny of the ITS, BenA, CaM and RPB 2 gene regions of species from Talaromyces. Branches with values more than 1 pp and 95 % bs are thickened, supports lower than those values are indicated with a dash (-). Trichocoma paradoxa (CBS 788.83 T) was chosen as outgroup. T: ex-type.

Figure 5. Talaromyces tenuis CBS 141840 T a colonies from left to right (top row) CYA, MEA, YES and OA; (bottom row) CYA reverse, MEA reverse, DG 18 and CREA b-g conidiophores and conidia. Scale bars: 10 μm (b-g).