The Messenger of Allah ﷺ said, "If one of you finds a louse on his garment, let him wrap it up and not throw it in the mosque."
حدثنا إسماعيل حدثني حجاج الصواف عن يحيى بن أبي كثير عن الحضرمي بن لاحق
أن رسول الله ﷺ قال إذا وجد أحدكم القملة في ثوبه فليصرها ولا يلقيها في المسجد
No references are available.
Its isnad is sahih. Hadrami bin Lahiq Tamimi, the storyteller, is reliable, and has narrations recorded by Nasai and Abu Dawud. Haythami said in 2/20, "Its narrators are deemed reliable."