Source rule
وَلَا يَفْسُدُ الْمَاءُ بِمَوْتِ مَا لَا دَمَ لَهُ فِيهِ كَسَمَكٍ وَضِفْدَعٍ وَحَيَوَانِ الْمَاءِ وَبَقٍّ وَذُبَابٍ وَزُنْبُورٍ وَعَقْرَبٍ
• The text exempts animals without flowing blood and aquatic creatures, such as fish, aquatic frogs, flies and scorpions.
• The commentary notes an important qualification: a land frog with flowing blood is not treated like an aquatic frog.