Subspecies
Spilornis minimus (Sibley and Monroe 1990, 1993) has been split into Great Nicobar Serpent-Eagle (Spilornis klossi) with the remainder (i.e. nominate minimus) lumped with Crested Serpent-Eagle (Spilornis cheela) following Rasmussen and Anderton (2005).
Considered by some authors to be a subspecies of Crested Serpent-Eagle (Spilornis cheela).