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Phragmidium mexicanum (Mains) H.Y. Yun, Minnis & Aime

Description
Uredinia on lower leaf surface, subepidermal, erumpent, round or ellipsoidal, 0.5 mm, hyaline, subhyaline to yellow, peridium present.

Urediniospores globose or subglobose, apex obtuse, hyaline to subhyaline, 15‒20 × 15‒19 µm; wall 1.0‒1.5 µm thick, apex unthickened, densely echinulate.

Hosts
Host family: Rosaceae
Host species: Potentilla indica

Distribution
QLD

Comments
This rust was previously known as Frommeëlla mexicana. A systematic study by Yun et al. (2011) revealed Frommeëlla was a synonym of Phragmidium.

Highslide JS
Phragmidium mexicanum on Potentilla indica - BRIP 55383.
Highslide JS
Urediniospores of Phragmidium mexicanum on Potentilla indica - BRIP 55383.
Scale bar = 10 µm.