Fitzroyomyces pseudopandanicola S. C. He & D. P. Wei, sp. nov.

Index Fungorum number: IF 902253; Mycobank number: MB 902253; Facesoffungi number: FoF 16056; Fig. 1

Etymology: Phylogeny closely related to P. pandanicola, but morphology distinct.

Holotype: HKAS 134947

Saprobic on dead woody twig. Sexual morph: Apothecia 210–405×308–468 μm (x̄=271×382, n=10), cupulate, completely immersed in the substrate when immature and opening by entire pore at maturity. Disc deeply immersed, creamy yellow, splitting away from the margin when dry. Exciple 35–65 (x̄=46, n=20) μm, three-layered, with a prominent accessory thalline at the outermost layer, a wall of hyaline, thick-walled cells of textura angularis at the middle layer and a crystalliferous layer at the inner. Subhymenium 7.8–21 μm (x̄=15, n=25), composed of hyaline cell of textura angularis, J−. Periphysoidal layer not observed. Paraphyses 1.8–3.7 μm (x̄=2.6, n=20) in the wide, numerous, hyaline, filiform, apically branched. Asci 151–163×6.6–9 μm (x̄=157×7.6, n=10), 8-spored, unitunicate, cylindrical, widest in the middle, rounded apex. Ascospores 128–147×2.2–2.6 μm (x̄=137×2.4, n=10), hyaline, elongated cylindrical, slightly narrowing toward both ends, multiseptate, up to 20-septa. Asexual morph: Not observed.

Culture characteristics: Colony moderately growing on PDA media, reaching 2.1 cm after incubation for 30 days at 25 C. The colony was white to pale brown, raised, margin entire, mycelia dense, reverse brown.

Material examined: China, Yunnan Province, Xishuangbanna, on dead woody twig, 12 September 2022, De-Ping Wei, ST3 (HKAS 134947, Holotype), Ex-type, KUNCC 23–15,699.

GenBank numbers: ITS=OR769026, LSU=OR808083, mtSSU=PP832019, RPB2=OR775514.

Notes: Fitzroyomyces pseudopandanicola phylogenetically sister to F. pandanicola with strong support (100% ML and 1.00 BYPP). Fitzroyomyces pandanicola originally was recognized as a member of Stictis by Tibpromma et al. (2018). Later this species was transferred to Fitzroyomyces by Wei et al. (2021a, b) based on multigene phylogenetic analysis. Fitzroyomyces pandanicola was found on dead leave of Pandanus sp. in Xihuangbanna District, Yunnan Province, China. Our species shares similar morphology with F. pandanicola in the cupulate apothecia with a large opening. However, F. pseudopandanicola can be distinguished from F. pandanicola in the smaller asci (151–163×6.6–9 μm vs. 160–240×7.5–23 μm) and ascospores (28–147×2.2–2.6 μm vs. 190–265×4–5 μm) as well as the association with dead twig. Additionally, the sequence comparisons show 24 bp (4.4%) differences in a 541 bp fragment of ITS between F. pseudopandanicola and F. pandanicola.

Figure 1 – Fitzroyomyces pseudopandanicola (HKAS 134947, holotype) a–c Apothecia on substrate. d, e Vertical section of apothecia. f, g Exciple. h Hymenium. i, j Asci and paraphyses. k, l Ascospores. m Ascus cap. n Upper and lower view of culture on PDA. Scale bars: d, e, g=250 μm, f, h–j=50 μm, k, l=25 μm, m=5 μm. (i, j, l, and m were treated with Melzer’s reagent)