Aposphaeria pulviscula (Sacc.) Sacc.,Michelia 2(no. 6): 4 (1880)
Phoma pulviscula Sacc., Michelia 1(no. 2): 259 (1878)
Coniothyrium pulviscula (Sacc.) Kuntze, Revis. gen. pl.
(Leipzig) 3(2): 459 (1898)

Saprobic on plants in terrestrial habitats. Mycelium immersed, branched, septate, brown. Conidiomata (56−)84–133μm high×(30−)54–100μm diam. (x̅=93×87 μm, n=10), pycnidial, gregarious, superficial or semi-immersed, globose to subglobose, black, ostiolate. Ostiole single, circular, central. Pycnidial wall 9–13μm (x̅=11μm, n=10), comprising a single layer of thick-walled, brown cells of textura angularis. Conidiophores 1–4μm, hyaline, septate, cylindrical, formed from the inner cells of the pycnidial base wall.
Conidiogenous cells enteroblastic, phialidic, hyaline, smooth. Conidia 2.3–2.8×0.8–1.4μm (x̅=2.5×1.2μm, n=10), hyaline, aseptate, thin-walled, eguttulate, cylindrical or ellipsoidal, smooth-walled.

Material examined: ITALY, Padova, in Salix udensis Trautv. & C. Meyer (Salicaceae), January 1878, Saccardo (IMI 202557, isotype, as ex-isotype of Phoma pulviscula).

Fig. 1 Aposphaeria pulviscula (isotype, from slides). a Herbarium label of Aposphaeria pulviscula. b–d Vertical sections through peridium. f–g Conidiogenous cells. Scale bars: b–c=50 μm, d–e=25 μm, f–g=5 μm

Fig. 2 Aposphaeria pulviscula (re-drawn from Sutton 1980, isotype). a Conidia. b Conidiophores. c Vertical section of a conidioma. Scale bars: a=5 μm, b=10 μm, c=25 μm