Anthostomella formosa  

Description derived from Francis, Mycological Papers 139: 75 (1975).

Anamorph: unknown.

Teleomorph: stromata absent, a clypeus not developing. Ascomata immersed below the epidermis on both surfaces of the substratum, perithecial, 210-310 µm tall and 240-300 µm diam, ± globose, with a conical papillate neck that projects only slightly from the substratum surface, often visible only through the accumulation of ascospores in a sticky mass on the substratum surface around the base of the neck. Peridium ca 18 µm thick, with an outer layer ca 10 µm thick of dark thick-walled cells and an inner layer ca 8 µm thick of hyaline thin-walled tissue. Interascal tissue composed of numerous paraphyses ca 3 µm diam. Asci 120-135 x ca 8 µm, cylindrical with a short tapered stalk, the apex rounded, appearing thickened but an apical ring is not visible in iodine. Ascospores 13.5-15.5 x 6-7 µm, ellipsoidal and slightly inaequilateral, two-celled, surrounded by a narrow gelatinous sheath. Upper cell 12-14 x 6-7 µm, brown, with an obtuse apex and a longitudinal germ slit 7-10 µm in length, apparently on a lateral face of the spore. Lower cell ca 1.5 x 2 µm, hyaline.