The Great Nicobar serpent eagle (Spilornis klossi), also known as the South Nicobar serpent eagle, is a species of bird of prey in the family Accipitridae. It is probably the smallest known eagle, with a weight of about 450g, a wingspan of 85to and a body length of about 38to.[1] [2] It is endemic to forest on the Indian island of Great Nicobar. It is threatened by habitat loss.
All major authorities now treat the Great Nicobar serpent eagle as a species, but in the past it was sometimes considered a subspecies of S. minimus. Today S. minimus is either considered a subspecies of the crested serpent eagle or a monotypic species from the central Nicobar Islands, the Central Nicobar serpent eagle.