Gall on creeping thistle (Cirsium arvense) caused by Urophora cardui (thistle gall fly)

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Size: 4288px × 3216px
Location: Oxfordshire, UK
Photo credit: © Helen White / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ., arvense, asteraceae, asterales, biology, botany, california, canada, canadian, cardui, caused, cecidia, cirsium, corn, creeping, cursed, cynareae, entomology, field, fly, gall, green, hard, hell, lettuce, perennial, prickly, small-flowered, thistle, urophora