Vonarxella Bat., J.L. Bezerra & Peres, Riv. Patol. veg., Pavia, sér. 4 1(1-2): 61 (1965).

Index Fungorum Number: IF5753

Epiphytic on the lower surface of leaves. Mycelium not observed. Sexual morph: Ascostromata superficial, solitary, black, flattened, circular, easily removed from the host surface, multi-loculate, hemispherical, lacking ostioles, upper wall composed of meandering cells, arranged and branching from the central to the outer rim. Peridium thin-walled, composed of dark brown to black pseudoparenchymatous cells, arranged in a textura angularis, comprising irregular meandering arrangement of dark brown, compact cells, poorly-developed at the base. Hamathecium comprising numerous, septate, hypha-like pseudoparaphyses, embedded in a gelatinous matrix. Asci 8-spored or more, bitunicate, fissitunicate, cylindro-clavate to clavate, with an ocular chamber, with or without pedicel, asci arising from the base of the ascomata. Ascospores overlapping 3–4seriate, hyaline, obovoid to ellipsoidal, 1-septate, apical cell wider and shorter than lower cell, lower cell narrow and tapering to rounded base. Asexual morph: Undetermined.

Type species: Vonarxella dipterygis Bat., J.L. Bezerra & Peres

Notes: The genus Vonarxella (Saccardiaceae) has only one species, with V. dipterygis as the type species. This was found on leaves of Dipteryx alata in Brazil in 1965. Vonarxella is similar to Schizothyrium. It is possibly a member of Schizothyriaceae (Phookamsak et al. 2016) based on ascostromata that are flattened, multi-loculate, a peridium that comprises irregular meandering arrangement of dark brown, compact cells, poorly-developed at the base, and ascospores that are 1septate, slightly constricted at the septum, and wider in upper cell. Thus, we classify Vonarxella in the Schizothyriaceae.

Species

  • Vonarxella dipterygis