Cytospora ampla Ning Jiang, Persoonia 55: 389 (2025)

Fig. 4

Description.

Sexual morph: Stromata Group SIII (type s 8), immersed in the bark, erumpent through the surface when mature, without extending to a large circular area. Conceptacle absent. Disc light grey, surrounded by ostiolar, circular to ovoid, 64–206 µm in diam, with 12–18 ostioles irregularly circularly in the disc. Ostioles umber to black when mature, arranged regularly in a disc, flask-shaped to spherical, 73–201 µm in diam. Asci hyaline, with a chitinoid, refractive ring, clavate to elongate-obovoid, 60–77 × 11–13 (av. = 46.4 ± 1.9 × 9.4 ± 0.7, n = 30) µm, 4 - spored. Ascospores hyaline, elongate-allantoid, thin-walled, aseptate, 18.8–24.0 × 4.5–6.2 (av. = 20.2 ± 0.4 × 5.3 ± 0.8, n = 50) µm. Asexual morph: not observed.

Culture characteristics.

Colonies initially white and entirely covering the 6 cm Petri dish after 5 d, becoming olivaceous buff to slight helical after 14 d. The colonies are flat, felt-like, thin with a uniform texture.

Materials examined.

China, Hebei Province, Saihanba, 42°23'33"N, 117°22'17"E, from branches of Malus spectabilis, 11 September 2024, C. M. Tian, T. Q. Pei & M. H. Wang (BJFC -S 2549, living cultures CFCC 72603; BJFC -S 2550, living culture CFCC 72604); 42°23'33"N, 117°22'17"E, from branches of Salix matsudana, 8 July 2024, C. M. Tian, T. Q. Pei & Y. Y. Wu (BJFC -S 2551, living culture CFCC 72627).

Notes.

Cytospora ampla was initially isolated from branches of Salix sp. and Rubus biflorus in Xizang, China. This species is characterized by its sexual morphs having four-spored asci (Jiang et al. 2025 a). In the present study, we obtained three new isolates (CFCC 72603, CFCC 72604, and CFCC 72627) from Malus spectabilis and Salix matsudana. These isolates clustered robustly with the ex-type isolate CFCC 71044 (Fig. 3) with high support (MLBP / BPP = 92 / 1.00), confirming their identification as C. ampla. Therefore, this represents a new host record (M. spectabilis) for C. ampla and its first occurrence in Hebei Province, China.