Square-tailed Drongo-Cuckoo

The square-tailed drongo-cuckoo is a cuckoo that resembles a black drongo. It is found along the Himalaya extending east into Southeast Asia. It can be distinguished by its downcurved beak, the white-barred vent and outer undertail, and a tail only notched, with slightly flared tips. Its calls are series of piercing, sharp whistles rising in pitch but delivered shrilly and choppily. It once included the fork-tailed drongo-cuckoo as a subspecies, but that form is now treated as a separate species (Wikipedia, general species account).