Pseudothielavia terricola X. W. Wang & Houbraken 2019

Pseudothielavia terricola X. W. Wang & Houbraken (2019) Fig. 32 Description. Sexual morph Cleistothecia 105–145 µm diam, non-ostiolate, globose, glabrous, black when mature, solitary to aggregated, mostly superficial, some submerged in PDA, aerial mycelium covered. Peridium brown, semi-translucent, membranous, textura epidermoidea. Asci subglobose to pyriform, hyaline when immature, eight-spored, 23.7–27.0 µm × 20.5–23.5 µm (x ̄ = 25.5 × 22.5 µm, L / W ratio = 1.13, n = 10). Ascospores 1 celled, olivaceous brown when mature, subglobose to ellipsoidal, some smooth, apical germ pore, 9.3–11.7 µm × 6.7–9.0 µm (x ̄ = 10.5 × 7.6 µm, L / W ratio = 1.39, n = 20). Asexual morph undetermined. Culture characteristics. Colony reaching 50 mm diam with thick white aerial mycelium, fluffy, edge irregularly, wavy margin, and similar to reverse side of the colony. Material examined. TAIWAN • Guanshan Township, Taitung County, 23°02'12.8"N, 121°11'22.0"E, serpentine soil in rice field, 2 nd November 2022, K. W Cheng, living culture NTUPPMCC 22-293 and NTUPPMCC 22-294. Notes. Two strains (NTUPPMCC 22-293 and NTUPPMCC 22-294) isolated in this study clustered within the clade containing ex-type strains, along with other representative strains of Pseudothielavia arxii and Pse. terricola, with strong statistical support (100 % / 1.00) (Fig. 33). Although both Pse. arxii and Pse. terricola exhibited no clear phylogenetic variation in our tree or in previous studies, they can be distinguished by differences in ascospore morphology (Wang et al. 2019). The morphology of our strain (NTUPPMCC 22-294) exhibited an apical germ pore, similar to that of Pse. terricola (CBS 165.88) (Fig. 32). According to its original description (Wang et al. 2019; Noguchi et al. 2022), Pse. arxii lacks an apical germ pore and instead possesses an oblique to lateral germ pore. Therefore, based solely on morphological similarity, we identified our strain as Pse. terricola. However, further studies are required to determine whether Pse. arxii and Pse. terricola represent two distinct species or a single species. This study represents the first discovery of a Pseudothielavia species in Taiwan.