Zymoseptoria Quaedvl. & Crous, in Quaedvlieg et al., Persoonia 26: 64 (2011).
Index Fungorum number: IF 517922; Facesoffungi number: FoF 08575, 8 morphological species (Species Fungorum 2022), 8 species with molecular data.
Foliicolous, associated with leaf spots. Sexual morph: Unknown. Asexual morph: Conidiomata pycnidial, semi-immersed to erumpent, dark brown to black, subglobose, with central ostiole; wall of 3–4 layers of brown textura angularis. Conidiophores hyaline, smooth, 1–2-septate, or reduced to conidiogenous cells, lining the inner cavity. Conidiogenous cells tightly aggregated, ampulliform to doliiform or subcylindrical, phialidic with periclinal thickening, or with 2–3 inconspicuous, percurrent proliferations at apex. Type I conidia solitary, hyaline, smooth, guttulate, narrowly cylindrical to subulate, tapering towards acutely rounded apex, with bluntly rounded to truncate base, transversely euseptate; hila not thickened nor darkened. On OA and PDA aerial hyphae disarticulate into phragmospores (Type II conidia), that again give rise to Type I conidia via microcyclic conidiation; yeast-like growth and microcyclic conidiation (Type III conidia) common on agar media (adapted from Quaedvlieg et al. 2011).
Type species: Zymoseptoria tritici (Roberge ex Desm.) Quaedvl. & Crous
Notes: Zymoseptoria is unique in producing three types of conidia. Zymoseptoria is a morphologically and phylogenetically well-supported genus in Mycosphaerellaceae. Molecular markers available for Zymoseptoria include ITS, LSU, BTUB, GAPDH, Histone, RPB2 and TEF-1.