Nafi' reported that he heard Abu Lubaba informing Ibn 'Umar that Messenger of Allah ﷺ had forbidden the killing of domestic snakes. (Using translation from Muslim 2233f)   

«أَنَّ رَسُولَ اللَّهِ ﷺ نَهَى عَنْ قَتْلِ الضِّفْدَعِ»  

“The Messenger of Allah ﷺ forbade killing four kinds of animals: Ants, bees, hoopoes and shrikes.” (Using translation from Ibn Mājah 3224)  

نَهَى رَسُولُ اللَّهِ ﷺ عَنْ قَتْلِ أَرْبَعَةٍ مِنَ الدَّوَابِّ النَّمْلَةِ وَالنَّحْلَةِ وَالْهُدْهُدِ وَالصُّرَدِ