Bisifusarium L. Lombard et al.

Bisifusarium L. Lombard et al. View in CoL , Stud. Mycol. 80: 223. 2015.

Sexual morph unknown. Conidiophores simple (aerial conidiophores) or grouped on sporodochia; aerial conidiophores simple, unbranched or irregularly branched, mostly reduced to terminal or single lateral conidiogenous cells. Conidiogenous cells often formed as (i) lateral phialidic pegs arising from superficial or submerged intercalary hyphal cells or, (ii) cylindrical and slightly tapering towards apex or ampulliform, smooth- and thin-walled monophialides, rarely polyphialides, with inconspicuous or absent periclinal thickening, solitary or aggregated to represent a poorly developed pionnotal sporodochial-like structure, producing micro- and macroconidia. Microconidia hyaline, thin-walled, 0–1-septate, ellipsoidal, allantoid, broadly lunate to reniform, straight or curved, tapering towards both ends. Sporodochial macroconidia falcate, (0–)1–2(–3)-septate, thick-walled, curved to lunate, with a blunt to hooked apical cell and obtuse to poorly developed, foot-shaped basal cell, typically formed on sporodochia. Sporodochia pale yellow to orange; sporodochial conidiophores verticillately branched and densely packed, consisting of short, smooth- and thin-walled stipes bearing an apical whorl of 2–3 monophialides; sporodochial conidiogenous cells monophialidic, cylindrical to subulate, smooth- and thin-walled, with reduced or flared collarette. Chlamydospores, if present, globose to subglobose to ellipsoidal, solitary or in chains, sometimes aggregated in sclerotia ( Lombard et al. 2015, Crous et al. 2021).

Type species: Bisifusarium dimerum (Penz.) L. Lombard & Crous

Notes: Bisifusarium was established to accommodate fusarioid species characterized by pionnotal culture growth, their short, chiefly 1–2-septate sporodochial macroconidia and the formation of lateral phialidic pegs arising from hyphae ( Gerlach & Nirenberg 1982, Schroers et al. 2009, Lombard et al. 2015). Bisifusarium forms a well-supported clade ( BS = 100 %, PP = 1.0) closely related but separate from Fusarium s. str. ( Crous et al. 2021).