Tumularia aquatica  

Anamorph: Conidiomata absent. Conidiophores 20-60 µm long, 2-3 µm broad, bearing a single terminal conidium.  Conidia 24-34 x 12-16 µm, hyaline and usually two-celled with the upper cell much larger than the lower. Three-celled conidia have a large middle cell with a small one above and below it. Occasionally the spores are unicellular.

Teleomorph: Ascostromata perithecial, 300-500 µm diam, ± spherical, immersed in herbaceous tissue with a flush ostiole, visible from the surface as a black ring surrounding a pale central part; erumpent to superficial on woody substrata. Interascal tissue composed of branched septate pseudoparaphyses ca 1.5 µm diam, sparsely anastomosing above the asci. Ascospores 22-29 (-34) x (3.5-) 4-5 µm, fusiform, hyaline, with a constricted ± median septum and with the wall bulging slightly above and below the septum, the upper cell sometimes slightly shorter and wider than the lower cell, the ends acute, surrounded by a gelatinous sheath 1-2 µm thick, sometimes extended at the apices. Senescent ascospores usually 3-septate and pale brown.