Phragmidium mexicanum (Mains) H.Y. Yun, Minnis & Aime
Urediniospores globose to subglobose, apex obtuse, hyaline to yellow when fresh, 16-18 × 16-18 µm; wall 1.0-1.5 µm thick, apex unthickened, densely echinulate.
Telia on lower leaf surface, subepidermal, erumpent, dome-shaped, black, peridium present.
Teliospores cylindrical, apex rounded, 3 celled to 4 or more celled, reddish brown, 47-74 × 22-27 µm; wall 2-3 µm thick, 3-5 µm thick at apex, smooth, pedicel persistent, up to 43 µm.