The crested serpent eagle ("Spilornis cheela") is a medium-sized bird of prey. It is found in forested habitats across tropical Asia. It is found in a wide range across the Indian Subcontinent, Southeast Asia and East Asia. There are a number of variations and some authorities prefer to treat several of its subspecies as completely separate species. In the past, several species including the Philippine serpent eagle ("S. holospila"), Andaman serpent eagle ("S. elgini") and South Nicobar serpent eagle ("S. klossi") were treated as subspecies of the Crested serpent eagle.