Juxtiphoma yunnanensis Yasanthika, G.C. Ren & K.D. Hyde, 2021

Yasanthika, Erandi, Wanasinghe, Dhanushka N., Ren, Guang-Cong, Karunarathna, Samantha C., Tennakoon, Danushka S., Monkai, Jutamart, Gui, Heng, Mortimer, Peter E., Lumyong, Saisamorn & Hyde, Kevin D., 2021, Taxonomic and phylogenetic insights into novel Ascomycota from contaminated soils in Yunnan, China, Phytotaxa 513 (3), pp. 203-225 : 212-214

Juxtiphoma yunnanensis Yasanthika, G.C. Ren & K.D. Hyde , sp. nov.

Index Fungorum number: IF558129, Facesoffungi number: FoF09617, FIGURE 4 .

Etymology—The specific epithet “ yunnanensis ” refers to Yunnan Province ( China), where the species was collected.

Holotype — HKAS 107656

Culture characteristics:— Colonies on PDA reach to 4–6 cm diam. after 21 days at 25 °C, becoming flattened with irregular to lobate margins. Mycelium have a cottony to wooly surface, center is smoke grey to olivaceous grey becoming pale brown to brownish yellow at margin; reverse dark grey to black at the centre, with pale brown to brownish yellow at the edge. Hyphae 2–5 μm wide, aerial to semi-immersed and branched, hyaline aseptate, immature hyphae become pale brown septate when mature. Chlamydospores produced from mature hyphae, terminal or intercalary, solitary, or in simple or branched chains, barrel-shaped, globose to subglobose or ellipsoidal to elongated, pale brown to brown, becoming 2–8 guttulate when mature, 4–11 × 3–7 µm (x̄ = 7 × 5 μm, n = 20).

Material examined:— China, Yunnan Province, Kunming City , 25.047865N 102.721724 E, industrial wastecontaminated soil, 16 December 2019, G.C. Ren ( HKAS 107656 , holotype); ex-type living culture, KUMCC 20- 0227 .

Known hosts and substrates:— Soil

Known distribution:— China

GenBank Accession No:— ITS: MW 600334 , LSU: MW 587029 , btub: MW 602383 , rpb 2: MW 603001 .

Notes:— Juxtiphoma is a poorly studied genus with only two species viz. J. eupyrena and J. kolkmaniorum ( Species Fungorum 2021) . Juxtiphoma eupyrena has dark green colonies becoming black due to chlamydospore formation on Oatmeal Agar ( OA), while J. kolkmaniorum has an isabelline to olivaceous colony. Juxtiphoma yunnanensis ( KUMCC 20-0227) has smoke grey to olivaceous grey colonies becoming pale brown to brownish yellow at the margin on PDA. Both J. kolkmaniorum and J. eupyrena have conidia-bearing pycnidia on cultures in OA ( Valenzuela-Lopez et al. 2018, Hou et al. 2020). However, we did not see any pycnidial formation of Juxtiphoma yunnanensis ( KUMCC 20-0227) colonies in PDA. Nevertheless, Juxtiphoma yunnanensis ( KUMCC 20-0227) has abundant chlamydospores formation on PDA culture, which is a common character to Juxtiphoma ( Valenzuela-Lopez et al. 2018, Hou et al. 2020). The combined phylogenetic analysis (ITS-LSU- btub -rpb 2) indicates that our new strain constitutes a distant lineage from Juxtiphoma eupyrena and J. kolkmaniorum with 99% ML, 1.00 BYPP statistical support ( FIGURE 1 ). We introduce this novel lineage as Juxtiphoma yunnanensis sp. nov., which was isolated from industrial waste-contaminated soil in Kunming City, Yunnan Province, China.

Figures

FIGURE 1. RAxML tree inferred from the combined dataset of ITS-LSU-rpb2-btub partial sequences of strains of Didymellaceae. Bootstrap support values for maximum likelihood (ML) values equal to or higher than 60% and Bayesian posterior probabilities (BYPP) equal to or greater than 0.95 are given above each branch, respectively. The new isolate is in blue bold. Ex-type strains are in black bold. The tree is rooted to Leptosphaeria conoidea (CBS 616.75) and L. doliolum (CBS 505.75). The scale bar represents the expected number of nucleotide substitutions per site 0.08.

FIGURE 4. Juxtiphoma yunnanensis (HKAS 107657, holotype) a. Colony from above. b. Colony from below. c. Mycelia appear on the colony. d. Immature aseptate hyphae e. Mature septate hyphae. f. Terminal branched and chained chlamydospores formation. g, h. Intercalary and solitary chlamydospores formation. i. Solitary and simple chlamydospores formation j–m. Chlamydospores chains. Scale bars: e = 25 μm, d, f, j = 20 μm, g, h, i, k–m = 10 μm