Anamorph: conidiomata formed as locules within the stroma, strongly convoluted, with a single wide central opening. Conidia 5-7 x 1 µm in size.
Teleomorph: stromata 2-3 mm diam., containing around 8 ascomata. Ectostromatic disc pale when young, when mature dark grey-brown. Entostroma light grey, flattened at the base, delimited by an unbroken black zone line, the surrounding bark fulvous brown. Ascomata perithecia, circinate, 500-700 µm diam., angular by mutual pressure, the necks convergent, thick (160-180 µm diam.). Peridium ca 30 µm thick, composed of olivaceous angular cells 15-25 µm diam., the neck canal very wide, 70-90 230m diam. Asci 50-65 x 8-11 µm, narrowly clavate to subcylindrical, 8-spored; an apparently structureless apical thickening makes the lumen of the ascus truncate-concave at the top. Ascospores 10-18 (-25) x 3-4µm, allantoid.
Not formally identified, but would almost certainly be considered as Data Deficient due to under-reporting and possible confusion with Leucostoma persoonii.
Distinguished by its dark grey-brown ectostromatic disc and by host preference.
In GB&I, associated with Sorbus aucuparia; reported from other Sorbus species elsewhere. At least some records identified as Leucostoma persoonii may refer to this species.
In GB&I, the only confirmed report is from VC63 SW Yorkshire.
A canker-causing species affecting twigs and young branches, sometimes inducing dieback.