Conidial morph: Phomopsis sarothamni (Sacc.) Höhn. (1906). Alpha-conidia 8-10(-12) x 2 µm; beta-conidia 30-33 x 1 µm. Ascal morph: Stromata visible on the host surface as numerous minute pustulate erumpent elliptical to circular discs through which 1-3 ostioles are barely erumpent, entostroma evenly effuse and strongly differentiated and often somewhat limited in extent (1-5 cm), surrounded by a black zone line. Ascomata 400-500 µm diam., ± globose with a ± curved cylindrical neck to ca 700 µm diam., in clusters of 2-6 with the necks convergent. Interascal tissue of broad very thin-walled paraphyses to 7 µm diam., sparsely branched and tapering towards the apex, deliquescent at maturity. Asci 61-71 x 10.5-12.5 µm, cylindric-clavate, thin-walled and not fissitunicate, almost sessile and evanescent at the base and thus floating freely within the ascoma, the apex obtuse with a conspicuous refractive apical ring, not blueing in iodine but staining in fountain-pen ink, 8-spored . Ascospores arranged biseriately, (11-) 11.5-14.5 (-16.5) x 4-5 (-5.5) µm, fusiform-clavate, usually with a distinctly constricted median to slightly submedian septum but with a proportion of spores fusiform and aseptate, hyaline, smooth- and thin-walled, guttulate, without a gelatinous sheath or appendages.