In most of its range in Asia, this is the largest of the drongo species and is readily identifiable by the distinctive tail rackets and the crest of curled feather that begin in front of the face above the beak and along the crown to varying extents according to the subspecies. The tail with twirled rackets is distinctive and in flight it can appear as if two large bees were chasing a black bird. In the eastern Himalayas the species can be confused with the
lesser racket-tailed drongo, however the latter has flat rackets with the crest nearly absent. This widespread species includes populations that have distinct variations and several subspecies have been named. The nominate form is found in southern India, mainly in forested areas of the Western Ghats and the adjoining hill forests of peninsular India. The subspecies in Sri Lanka is
ceylonicus and is similar to the nominate form but slightly smaller. The subspecies found along the Himalayas is
grandis and is the largest and has long glossy neck hackles. The Andaman Islands form
otiosus has shorter neck hackles and the crest is highly reduced while the Nicobars Island form
nicobariensis has a longer frontal crest and with smaller neck hackles than
otiosus. Specimens of the nominate form have sometimes been confused with the Sri Lanka drongo. Considerable variation in shape of the bill, extent of the crest, hackles and tail rackets exists in the island populations of Southeast Asia. The Bornean
brachyphorus (=
insularis),
banguey of
Banggai lack crests (
banguey has frontal feathers that arch forwards) while very reduced crests are found in
microlophus (=
endomychus; Natunas, Anambas and Tiomans) and
platurus (Sumatra). A number of forms are known along the Southeast Asian islands and mainland including
formosus (Java),
hypoballus (Thailand),
rangoonensis (northern Burma, central Indian populations were earlier included in this) and
johni (Hainan). Young birds are duller, and can lack a crest while moulting birds can lack the elongate tail streamers. The racket is formed by the inner web of the vane but appears to be on the outer web since the rachis has a twist just above the
spatula. ==Distribution and habitat==