Uredinia: small, hypophyllous, sometimes mixed with telia. Urediniospores 17-20 x 14-19 µm, ovoid to ellipsoidal, the wall ca 1.5 µm thick (measurements in water), verrucose.
Telia: small, hypophyllous. Teliospores 22-29 x 13-15 (measured in warmed lactic acid), the length/breadth ratio rather variable, ± clavate, 2-celled, hyaline to pale yellow, smooth, thin-walled.
Not formally assessed but the host is introduced and the fungus presumably also.
On living leaves of cultivated Oxalis sp.
Widespread in southern England, more local further north, as far as Edinburgh and Islay. Common in Ireland.