Gymnosporangium amelanchieris

On living leaves attached to the branch of Amelanchier ovalis.

This study corresponds to the aecial stage of the species.

Peridial hyphae of the aecia irregular, rectangular, polyhedral, very thick-walled with a hyaline lumen, the wall ornamented with radially arranged striations, measuring up to 50 µm long.

Aeciospores globose to subglobose, smooth- and thick-walled, greenish-brown under the microscope, with a wall thickness of 1.7-2.5 µm.

Herbarium material available: JTP2197/24.