Diplocarpon rosae

Fructifications appearing as black foliar spots (acervuli) erupting through the leaf epidermis to release conidia.

Conidiogenous cells arising from the mycelium producing a single conidium.

Upon detaching and maturing, conidia develop a central septum dividing them into two unequal cells with a strong constriction at the septum; conidia fusiform to slightly curved (shoe-shaped), with one cell more swollen, hyaline, containing abundant oil droplets.