Sporocadus prunicola C. M. Tian & Ning Jiang sp. nov.

Fig. 4

Etymology.

Named after the host genus Prunus and and “- cola ” = “inhabiting”.

Description.

Associated with branch canker disease of Prunus cerasifera. Teleomorph. Undetermined. Anamorph: Conidiomata acervular, solitary or gregarious, semi-immersed, subglobose, superficial to semi-immersed, pale luteous, 98–431 μm diam, 153–289 μm high. Conidiophores septate, branched at base, hyaline, smooth. Conidiogenous cells discrete, filiform, hyaline, smooth, 18–45 × 1–2 μm. Conidia straight or slightly curved, subcylindrical, with round ends, brown, 3 - septate, septa darker than the rest of cell, wall smooth and slightly constricted at the septa, (10.5 –) 12–15 (– 16.5) × (3 –) 3.5–4.5 (– 7) μm (x ̄ = 13.4 × 4.2 μm, n = 50), L / W = 2.8–3.7, lacking appendages; basal cell obconic with round base, pale brown, paler than other cells, thick-walled, 3–3.5 μm long; median cells doliiform, brown, 2.5–4 μm long; apical cell conic with a wide round apex, brown, 2.5–4 μm long.

Culture characteristics.

Colonies on PDA flat, spreading, with abundant flocculent aerial mycelium and entire margin, isabelline, fast growing, reaching 90 mm diam after 2 wk at 25 ° C, sterile. Colonies on MEA flat, spreading, with moderate aerial mycelium and feathery margin, white to pale gray, fast growing, reaching 90 mm diam after 2 wk at 25 ° C, sterile.

Materials examined.

China • Xizang Autonomous Region (Tibet), Linzhi City, Bayi District, Xizang Agriculture and Animal Husbandry University, 29°39'59"N, 94°20'20"E, 3007 m asl, from cankered branches of Prunus cerasifera, 8 Jul. 2024, Ning Jiang, Jieting Li, Yi Li & Ji Qiang (holotype CAF 800149, ex-holotype cultures CFCC 71042 and CFCC 71288).

Notes.

Sporocadus prunicola, isolated from Prunus cerasifera in Xizang, is phylogenetically closely related to Sp. incanus (from Prunus dulcis in Spain) and Sp. italicum (from Crataegus sp. in Italy) (Fig. 1). Morphologically, Sp. prunicola possesses significantly smaller conidia than those of Sp. incanus (12–15 × 3.5–4.5 μm vs. 11.5–20 × 4.5–6.5 μm). Furthermore, Sp. prunicola can be clearly distinguished from Sp. incanus by 1 / 515 bp in ITS, 1 / 830 bp in LSU, 25 / 832 bp in rpb 2, 29 / 289 bp in tef 1, and 45 / 712 bp in tub 2. It also differs from Sp. italicum by 2 / 534 bp in ITS and 4 / 881 bp in LSU (Hyde et al. 2017; Liu et al. 2019). PHI analysis further supports the status of Sp. prunicola as a distinct species, showing no evidence of recombination with its closest relatives (P = 1.0) (Fig. 2).