BEagle
But the Mirage family are all descended from the FD2
The 1st Mirage flew on June 25th 1954 (more inspired by the Convair Delta, initially), whereas the FD2 flew in October 1954. No doubt that Dassault learnt a lot from the FD2
test flights at Cazaux (the Mirage III's first fligh was indeed after the Cazaux test flights), but after all, it was the English government who prohibited supersonic flights over Great Britain
