Flammeascoma ryskae Mlčoch, 2025

Flammeascoma ryskae Mlčoch sp. nov. —fig. 2, 3.

Holotype. BRNM 847516 About BRNM

MycoBank no. 857366

Etymology. The species name is named after a famous Czech phytopathologist, Anna Ryšková.

Sexual morph. Ascoma subglobose to globose, in numerous groups, partially nested in the wood to superficial, 210–290 μm in diameter. Ostioles central, very broad to conical, irregular. Ascomal wall composed of several layers of pseudoparenchymatous cells, composed of dark brown polygonate cells of textura angularis to textura epidermoidea. (3.5) 4–4.5 (6) × 3–3.5 (4.5) μm, N =10. Hamathecium is composed of numerous, narrow, cellular hyaline pseudoparaphyses. Asci bitunicate, 8-spored, cylindrical to cylindric-clavate, short pedicellate, 63.7–76.6 (80) × 6.2–7.4 (7.5) µm, N =10. Ascospores 1 to 2-seriate in asci, fusiform, subhyaline to brownish, becoming brown, when released from asci and germinating, 1 to 3-septate, second cells enlarged, without gelatinous sheath, appendages and ornamentation, with several globose lipid drops, (15) 16–20 (20.6) × (3) 3.5–4.7 (5) µm, Q =3.9–5.4, Q AV =4.6, N =23. Asexual morph. Undetermined.

Culture characters. Growth is very slow and variable, colony only 4–5 mm in diameter. After 2 weeks on PDA at 25 °C and 12–16 mm, after 1 month on PDA at 25 °C. Colony irregular, primarily whitish to greyish on the surface, with rosy to reddish zones at the edge, often dyes of medium, later the color disappears. The oldest colony after one month on PDA irregular with convex to umbonate elevation, margin undulate, greyish at the edge, dark grey to black at the centre, concentrically colored. Pycnides in culture globose, to 350 µm in diam., with a very unremarkable ostiole. Pycnidial wall composed of several layers of dark brown pseudoparenchymatous cells, 5–7.5 × 5–5.5 µm, N=10. Interior lined with palisade of hyaline to pinkish lageniform to cylindric conidiogenous cells, 17–24 × 3 µm, N=10. Conidia subglobose to globose, often ellipsoid to oblong, hyaline, 1-celled, with rounded ends, smooth, with 2 lipid oils, (3) 3.7–4.5 (5) × (1.5) 2–2.5 (2.7) µm, Q=1.8–2.5, Q AV =2.1, N=30.

Habitat. On dead wood of deciduous trees, known from the dead wood of Tilia cf. cordata . Found in the floodplain forest of the Tilio-Carpinetum association in the lowland grade.

Distribution. Known from the Czech Republic.

Material examined. Czechia, Moravian Gate, Suchdol nad Odrou, Bařiny nature reserve, floodplain forest, in Tilio-Carpinetum, 260 m a.s.l., on the dead wood of Tilia cf. cordata , 16. September 2021, Col. P. Mlčoch, 847516 ( BRNM, holotype), GPS: 49.6324322N, 17.9576669E.

Notes. Phylogenetic analyses of the sequence data of the ITS and LSU regions indicated that this collection of new taxa belongs in Anteagloniaceae . This taxon is closely related to the genera Anteaglonium and Flammeascoma . Morphologically, it is related to the Flammeascoma , because ascoma it isn’t hysterothecial and ascospores it isn’t small, ellipsoid to ellipsoid fusoid, didymosporous, as in the case of the genus Anteaglonium ( Jaklitsch, Fournier & Voglmayr 2018; Jayasiri et al. 2016). Fusoid face and overall appearance of young spores rather resemble Flammeascoma bambusae ( Liu et al. 2015) and Flammeascoma lignicola ( Ariyawansa et al. 2015) . Flammeascoma ryskae is different from these two species on the basis of other dimensions of ascospores (less than 25 µm in length), the presence of 3-septate spore cells and brownish pigment in the old spores. This taxon also colors the cultivation medium red, as phylogenetically distant Anteaglonium rubescens ( Jaklitsch, Fournier & Voglmayr 2018) .