About Surniculus lugubris (Horsfield, 1821)
The square-tailed drongo-cuckoo, Surniculus lugubris (Horsfield, 1821), can be easily identified by its downcurved beak, white barred vent and outer undertail, and a tail that is only notched with slightly flared tips. A white wing-stripe is visible from below when the bird is in flight. This species is a brood parasite that lays its eggs in the nests of small babblers. It remains unknown how or whether the species' drongo-like appearance provides it with a benefit, but it is suspected to aid brood-parasitism in the same way that hawk-cuckoos' hawk-like appearances are thought to help their brood parasitism. The square-tailed drongo-cuckoo was formerly classified as conspecific with the fork-tailed drongo-cuckoo; the two together were called the Asian drongo-cuckoo. However, observed vocal and morphological differences led to the two being split into separate species.
