Musannaf Ibn Abi Shayba 3:2591

Abu Bakr narrated to us, he said: Ibn ‘Uyaynah narrated to us, from Ma‘mar, from Yahya, from Damdam, from Abu Hurayrah, that the Prophet, may Allah bless him and grant him peace, commanded the killing of the two black ones during prayer: the snake and the scorpion.