Apothecia immersed, opening by a pore and eventually splitting the overlying substrate irregularly, 0.3–0.6 mm diam., colourless throughout. Covering layer ca 50 µm thick, of vertically arranged pseudoparenchymatous cells ca 3 µm diam. Paraphyses filiform, unbranched, colourless, not enlarged above, I–. Asci cylindric-saccate, ca 70 × 10 µm, 8-spored. Ascospores long-cylindrical, not sheathed, 35–45 × 3–4 µm, closely septate, the cells 3–4 µm long.
This species appears not to have been collected since the original publication, and its status needs further investigation. The description has been modified from Sherwood (1980). She considered that the species is similar to Karstenia idaei, but with shorter asci.
On Clematis stems; presumably saprotrophic.
Cumbria, only known from the type collection.