Musnad Abu Ya'la al-Mawsili 159:56

Wahb ibn Baqiyyah narrated to us, Khalid narrated to us, from Abd al-Rahman, from Abu al-Zinad, from al-A'raj, from Abu Hurayrah, from the Prophet (may Allah bless him and grant him peace), who said: "A prophet from among the prophets descended under a tree, and an ant stung him. He ordered his equipment to be removed from under it, then he ordered it (the ant colony) to be burned, so it was burned. Then it was revealed to him: 'Was it not just one ant?'"