Phyllosticta wuzhishanensis M. Y. Zhang, Z. X. Zhang & X. G. Zhang 2025, sp. nov.

Phyllosticta wuzhishanensis M. Y. Zhang, Z. X. Zhang & X. G. Zhang sp. nov. Fig. 5 Etymology. The epithet “ wuzhishanensis ” pertains to Wuzhishan National Nature Reserve, where the type was collected. Type. China • Hainan Province, Wuzhishan National Nature Reserve, on saprophytic (dead leaves) leaves, 28 March 2024, M. Y. Zhang (holotype HSAUP 7814), ex-type living culture CGMCC 3.28670. Description. Endophytic on saprophytic (dead leaves) leaves. Sexual morph: Not observed. Asexual morph: Conidiomata pycnidial, mostly aggregated in clusters, black, erumpent. In PDA culture, exuding colorless to opaque conidial masses within 12 days or longer. Pycnidial walls multilayered, textura angularis, brown, inner walls of hyaline. Conidiophores indistinct, often reduced to conidiogenous cells. Conidiogenous cells 6.5–14.5 × 3–4 μm, subcylindrical, ampulliform, hyaline, smooth. Conidia 5.5–10 × 3.8–8.6 μm (L / W 1.27 –1.83), ovoid, ampulliform, ellipsoidal to subglobose, hyaline, aseptate, thin and smooth walled, multi-guttulate, or with a single large central guttule, surrounded by a mucilaginous sheath. Sheath 1.6–2 μm thick, thicker on both sides, and bearing a hyaline, apical mucoid appendage. Appendages 10–13 × 1.2–1.5 μm, flexible, unbranched, tapering towards an acutely rounded tip. Spermatia 6.3–8.2 × 1–1.5 μm, occurring in conidioma with conidia, hyaline, smooth, guttulate to granular, bacilliform. Culture characteristics. Colonies on PDA 17–21 mm in diameter after 14 days at 25 ° C in darkness, with a growth rate of 1.2–1.5 mm / day, undulate at edge, black on obverse and reverse. Additional specimen examined. China • Hainan Province: Wuzhishan National Nature Reserve, on saprophytic (dead leaves) leaves, 28 March 2024, M. Y. Zhang (HSAUP 7810), living culture SAUCC 7810–1. Notes. Phyllosticta wuzhishanensis is closely related to P. aspidistricola (NBRC 102244) based on DNA sequence data in BLAST searches and phylogenetic analysis (Fig. 1). However, P. wuzhishanensis differs from P. aspidistricola by 69 nucleotides (40 / 621 in ITS, 0 / 737 in LSU, 0 / 411 in tef 1, 29 / 252 in ACT, and 0 / 727 GPDH). In morphology, they are distinguished by different hosts (dead leaves vs. Aspidistra elatior) and conidial size (5.5–10 × 3.8–8.6 μm (L / W 1.27 –1.83) in P. wuzhishanensis vs. 9.5–12.5 × 8.5–10 μm (L / W 1.43 –1.63) in P. aspidistricola) (Motohashi et al. 2008). Based on morpho-molecular evidence, we establish this fungus as Phyllosticta wuzhishanensis sp. nov.