Leaf spots circular to irregular, to 10 (-20) mm diam., sometimes coalescing, pale to greyish or reddish brown, sometimes with a darker border.
Anamorph: conidiomata absent. Conidiophores mostly hypogenous, usually in clusters of 10-20, developing through stomata from a small immersed stroma, 40-65 x 4-5 µm (tending to be broader at the base), pale brown to brown, sometimes geniculate or sinuous, smooth, thin, irregular in width, usually narrower towards the tip, aseptate or sparingly septate, proliferating sympodially, the conidial scars 1.5–2.5 μm diam., conspicuous, thickened and darkened, terminal and lateral. Conidia 60-130 x 4-5 µm, cylindrical to filiform, usually straight but rarely slightly curved, often gradually tapering, smooth, thin-walled, 4- to 9- (-18) septate , the base obconical to truncate with a thickened and darkened hilum 1.5-2 µm diam., the apex acute.
Teleomorph: not known.
On living leaves of Armoracia rusticana, causing conspicuous leaf spots; also reported rarely from Nasturtium offiniale.
Southern England, occasionally north to Yorkshire.