Mahonia Rust - Cumminsiella mirabilissima
The rust fungus Cumminsiella mirabilissima affects the leaves of Berberis repens, Mahonia aquifolium and Mahonia japonica usually producing numerous small red spots on the upper leaf surface with brown uredinia beneath. Aecia are uncommon.

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Where the host plants occur.
When the host plants are in leaf, most often towards autumn.
Oligophagous.
Widespread in much of Britain.
Status in Leicestershire and Rutland not known.
Leicestershire & Rutland Map
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MAP KEY:
Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015