Hypospilina pustula  

Description contributed by Graham Kinsey (CABI).

Anamorph: unknown.

Teleomorph: stromata 0.3-0.5 mm diam, 0.3-0.5 mm broad, rounded, lenticular, slightly raised above both the upper and lower host leaf surfaces, visible mostly on the lower surface of the host leaf, with somewhat diffuse margins, exterior dark brown, interior occupied by a single ascoma. Ascomata perithecia, 250-350 µm diam, yellow-brown; necks laterally reaching 100-200 µm long, frequently inconspicuous but at maturity emerging beyond the host leaf surface by ca 200 µm. Peridium 10-12 µm thick, pale brown, composed of 4-5 layers of flattened cells, irregularly lobed in surface view. Interascal tissue not seen. Asci 60-75 x 8-16 µm, clavate to cylindrical-clavate, with a tapering base, apex somewhat truncate, thick-walled particularly near the apex, with a refractive apical ring, 8-spored, J-, becoming detached within the perithecial cavity but often remaining stuck together. Ascospores (13-)15-25 x 3.5-5 µm, mostly straight, 1-septate, the septum median, often 4-guttulate and giving the appearance of being 3-septate, without appendages.