Pestalotiopsis shanweiensis Q. C. Wang & X. D. Zhou 2025, sp. nov.

Pestalotiopsis shanweiensis Q. C. Wang & X. D. Zhou sp. nov. Fig. 12 Etymology. Named after the collection site of the type specimen, Shanwei City. Typus. CHINA • Guangdong Province, Shanwei City, Zhelang Street, 22°47'29"N, 115°32'18"E, on diseased leaves of Pinus massoniana, 27 August 2023, Quanchao Wang, Guoqing Li, Feifei Liu & Runlei Chang (holotype designated here HMAS 353940, dried culture prepared from ZXD 950; ex-holotype culture ZXD 950 = CFCC 72591). Description. Sexual state not seen. Conidiomata in culture sporodochial, saucer-shaped, scattered or gregarious, superficial to immersed, shining, releasing black conidial masses on the surface. Conidiophores branched, subcylindrical, hyaline to light brown, indistinct, often reduced to conidiogenous cells. Conidiogenous cells cylindrical or ampulliform, hyaline, smooth-walled, solitary to aggregated, (4 –) 5.5–10 (– 14) × 2–3.5 (– 5) μm (x ± SD = 7.7 ± 2.1 × 2.7 ± 0.7 μm). Conidia fusoid, ellipsoid, smooth, slightly constricted at the septa, 4 - septate, (17.5 –) 19–21.5 (– 22.5) × (5.5 –) 6–7 (– 7.5) μm (x ± SD = 20.1 ± 1.2 × 6.7 ± 0.5 μm); three median cells doliiform, wall verruculose, concolourous; (11.5 –) 12–14 (– 14.5) μm (x ± SD = 13 ± 0.9 μm) long; second cell from the base (3.5 –) 4–5 (– 6) μm (x ± SD = 4.6 ± 0.5 μm) long; third cell (3 –) 4–5 μm (x ± SD = 4.3 ± 0.5 μm); fourth cell (3 –) 3.5–4.5 μm (x ± SD = 4.1 ± 0.5 μm); apical cell conic with an acute apex, thin- and smooth-walled, hyaline to pale brown, (2 –) 3–4 μm (x ± SD = 3.3 ± 0.5 μm) long, with 2–3 tubular appendages (mostly three); apical appendages arising from an apical crest, unbranched, filiform, bent, (6 –) 11–17 (– 22) μm (x ± SD = 14.1 ± 3 μm); basal cell obconic with a truncate base, thin-walled, hyaline or pale brown, (2.5 –) 3–4 (– 4.5) μm (x ± SD = 3.7 ± 0.6 μm) long, with one appendage; basal appendage tubular, centric, unbranched, occasionally swollen at the tip, (3 –) 4–5.5 (– 6.5) μm (x ± SD = 4.7 ± 0.9 μm) long. Culture characteristics. Colonies forming abundant flocculent aerial mycelium at the edges on PDA at 25 ° C, with regular margins, white to isabelline, the back colony light orange, forming black conidiomata with black conidial masses. Optimal growth temperature at 25 ° C, no growth at 5 ° C and 35 ° C; after 10 d, colonies at 10, 15, 20, 25 and 30 ° C reached 31.8, 52.4, 74, 74.1 and 22.9 mm, respectively (Fig. 8). Additional materials examined. CHINA • Guangdong Province, Shanwei City, Zhelang Street, 22°47'29"N, 115°32'18"E, on diseased leaves of Pinus massoniana, 27 August 2023, Quanchao Wang, Guoqing Li, Feifei Liu & Runlei Chang (culture ZXD 951). Notes. Pestalotiopsis shanweiensis forms a well-supported independent clade (ML / BI = 100 / 1) and is phylogenetically distinct from Pes. licualicola, Pes. pandanicola and Pes. krabiensis (Fig. 3). In detail, Pes. shanweiensis was distinguished from Pes. licualicola, Pes. pandanicola and Pes. krabiensis in ITS (Pes. krabiensis: 6 bp, Pes. licualicola: 6 bp, Pes. pandanicola: 8 bp); tef 1 - α gene (Pes. krabiensis: 15 bp, Pes. licualicola: 3 bp, Pes. pandanicola: 8 bp); tub 2 gene (Pes. krabiensis: 12 bp, Pes. licualicola: 8 bp, Pes. pandanicola: 17 bp). Moreover, Pes. shanweiensis differs from Pes. krabiensis in having shorter, but wider conidia (Pes. shanweiensis: 17.5–22.5 × 5.5–7.5 μm vs. Pes. krabiensis: 19–25 × 4–6 μm), longer appendages (Pes. shanweiensis: 3–6.5 μm vs. Pes. krabiensis: 2–4 μm); Pes. shanweiensis differs from Pes. licualicola and Pes. pandanicola in having larger conidia (Pes. shanweiensis: 17.5–22.5 × 5.5–7.5 μm vs. Pes. licualicola: 16–20 × 3–5 μm, Pes. pandanicola: 13–18 × 2.5–4.5 μm). Based on both phylogenetic and morphological evidence, we propose the recognition of Pes. shanweiensis as a novel species.