Synarthonia inconspicua (Stirton) Van den Broeck & Ertz Fig. 5 Description. Sexual morph: Thallus crustose, thin, pale green, smooth, glossy, with obvious edge. Apothecia round to irregular shape, intensive, numerous, weakly concave, sessile, disk white, often forming irregular clusters of 0.4–0.7 × 0.2–0.5 mm. Disc brownish, with white pruina, flat to concave. Exciple uncarbonized. Epihymenium dark brown, 20–34 μm tall. Hymenium hyaline, 59–85 μm tall, not inspersed, I + reddish, K –, K / I + blue. Hypothecium brown, 11–24 μm tall. Paraphyses simple, unbranched, with colorless apices. Asci 8 - spored, hyaline, clavate, obovoid to ellipsoid, or (sub-) globose, with top ring structure, (37.0 –) 40.5 – 51.5 (– 52.50) × (20.5 –) 21.5–25.5 (– 26.0) μm (n = 10), I + reddish, K –, K / I –. Ascospores obovate, oblong-ovoid, 3 - septate, (16.0 –) 17.5–20.0 (– 21.0) × (5.5 –) 6.0–6.5 (– 7.0) μm (n = 20), I –, K –, K / I –. Asexual morph: not observed. Chemistry. Thallus K –, C –, KC –, Pd –, UV –. TLC: No lichen products detected. Material examined. China • Guizhou Province, Chishui City, Chishui Alsophila National Nature Reserve, 28°21'51"N, 105°59'55"E, 525 m elev., on bark, 12 July 2024, ShaoBin Fu, WeiWei Zheng, Coll. No. CS 80 (KUN-L 97468). Notes. In the phylogenetic analyses, our collection forms a well-supported clade (100 % bootstrap support) with Synarthonia inconspicua (Van den Broeck 7034, Van den Broeck 7013 B). Excluding gaps, no nucleotide difference was detected in the mtSSU (770 bp) region between our collection and reference specimens. Morphologically, this specimen agrees well with the description of S. inconspicua by Broeck et al. (2018), particularly in the presence of white pruina on the disc and in the size of ascospores (17.5–20.0 × 6.0–6.5 μm vs. 16.5–21.3 × 6.2–7.7 μm) (Broeck et al. 2018). Therefore, we identify this collection as Synarthonia inconspicua. This represents the first record of this species in Guizhou, China.

Published as part of He, Lin-Zhi, Wu, Wei, Bo, He-Yun, Chai, Lin-Shan, Jayawardena, Ruvishika S., Liang, Sheng, Meng, Qing-Feng & Fu, Shao-Bin, 2026, Two new lichenized species and a new record from Guizhou, China, pp. 73-96 in MycoKeys 128 on pages 73-96, DOI: 10.3897/mycokeys.128.170469