Tephritis arnicae is a species of picture-winged fly of the family Tephritidae, which are variously known as fruit-flies (North America) or gall flies (Britain and Ireland).
The larvae feed in the flowerheads of species of Arnica montana, Doronicum grandiflorum, D. austriacum and D. hungaricum.
It is found in the United Kingdom, Scandinavia, south to France, Bulgaria, and Ukraine.