Walnut Blister Mite - Aceria tristriata
The mite Aceria tristriata produces small blister like galls on the leaves of Walnut which often turn red. When a tree is severely affected the fruits may become galled as well.
Gall 
Adult 
Gall: Please provide photographs of the gall, showing both upper and lower surfaces of the leaf. Please also state the host species in the ‘comments’ section when submitting your record.
Galls may be found wherever Walnut trees occur.
When the host trees are in leaf.
True status in Britain is difficult to determine due to lack of records.
Status in Leicestershire and Rutland not known.
martindgrimes
Ketton LRWT Field
09 September 2020
martindgrimes
Ketton LRWT Field
09 September 2020
Melinda Bell
Main Street,Sheepy Magna
22 June 2022
upper surface
Melinda Bell
Main Street,Sheepy Magna
22 June 2022
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Yellow squares = NBN records (all known data)
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Species profile
- Species group:
- Mites, Ticks & Pseudoscorpions
- Kingdom:
- Animalia
- Order:
- Trombidiformes
- Family:
- Eriophyidae
- Records on NatureSpot:
- 9
- First record:
- 09/09/2020 (Grimes, Martin)
- Last record:
- 24/09/2024 (Timms, Sue)
Total records by month
% of records within its species group
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Melinda Bell
Main Street,Sheepy Magna
22 June 2022
lower surface
