Conioscypha pruni Y. C. Liao & Maharachch., 2025

Conioscypha pruni Y. C. Liao & Maharachch. , sp. nov.

MycoBank: 860245

Holotype:— HKAS 148727

Etymology:—The species epithet refers to the host genus where the fungus was collected.

Figure 2. Conioscypha pruni ( HKAS 148727, holotype). a–i Colonies on the natural substrate. a–c Colonies. d conidiogenous cells with attached conidia. e-i Conidia. j Germinating conidium. k, l Colony on PDA from above and below. m–q Sporulation observed on PDA. m, n Conidia and conidiogenous cell. o–q Conidia. Scale bars: d–j, m–q = 10 μm.

Saprobic on dead branches of sweet cherry trees. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Colonies on natural substratum, effuse, scattered to gregarious, brown, shiny, superficial. Mycelium partly superficial, composed of septate, branched, subhyaline hyphae. Conidiophores macronematous, often reduced to conidiogenous cells. Conidiogenous cells 2.5–4 μm wide ( x̄ = 2.91 μm, n = 10), enteroblastic, with a small cup-like collarette, hyaline, and smooth-walled. Conidia 6–10 × 3.5–5 μm ( x̄ = 7.52 × 4.53 μm, n = 30), pleuroacrogenous, aseptate, guttulate, cylindrical, with rounded apices, pale brown when young, dark brown when mature, smooth-walled.

Culture characteristics: Conidium germinated on PDA within 24 h. Colonies reaching a diameter of about 20 mm after 3 months at 25 °C, colonies from above: irregular margins, coriaceous, dry, pale yellow, distinct black punctiform pigmentation from the reverse. Mycelium hyaline, 1.5–2.5 µm wide. Conidiophores often reduced to conidiogenous cells, Conidiogenous cells hyaline, 2.0–2.5 µm wide, with cup-like collarette. Conidia hyaline to brown, subglobose to ellipsoidal, 6–13 × 3.5–6 μm ( x̄ = 8.39 × 4.36 μm, n = 30).

Material examined: CHINA. Sichuan Province:Chengdu City,Yunhua Mountain, Dujiangyan County, 31°00'74"N, 103°56'19"E, 1535 m, on the decaying branches of sweet cherry, 22 March 2024, Yan Jin, YHS5_1 ( HKAS 148727, holotype), ex-type living culture CGMCC 3.29000 = UESTCC 24.0251, HUEST 24.0263, isotype.

Notes: Phylogenetic analysis based on the combined dataset of ITS, LSU, SSU, RPB 2, and TEF 1 loci revealed that our collection ( HUEST 24.0263) forms a monophyletic clade sister to C. minutispora ( FIGURE 1 View FIGURE 1 ). In the NCBI BLASTn search, the closest match to our isolate ( UESTCC 24.0251) is C. minutispora . BLASTn analysis revealed 5.2% differences in ITS (436/460 bp, 8 gaps), 5.2% differences in LSU (626/661 bp, without gaps), and 99% sequence identity in SSU (938/940 bp, 2 gaps) between UESTCC 24.0251 and C. minutispora . Morphologically, UESTCC 24.0251 differs from C. minutispora by comparatively shorter conidiogenous cells (2.5–4 μm vs. 4–5 μm) and by narrower conidia (3.5–5 μm vs. 5–6 μm). Conidia of the new species are guttulate, ellipsoidal, contrasting with C. minutispora , which produces conidia with distinctly truncate bases and a central pore. Therefore, based on morphological and phylogenetic evidence, our isolate is proposed as a new species.