Treeswifts, belonging to the family Hemiprocnidae, are aerial birds found from India through Southeast Asia to New Guinea and the Solomon Islands. Comprising a single genus (Hemiprocne) with four species, these birds range from 15 to 30 cm in length, featuring long wings, crests or facial ornaments, and long, forked tails. They exhibit plumage that is softer than that of true swifts, and males sport iridescent feathers. Treeswifts possess certain anatomical differences from true swifts, notably in their skeletal structure and the presence of a nonreversible hind toe, allowing them to perch on branches—a trait not found in true swifts. Each species has different habitat preferences, with some like the whiskered treeswift living primarily in dense forest, while others occupy a range that includes deciduous woodlands and mangrove forests. These birds are insectivorous, although their specific diets have not been extensively studied. Treeswift mating pairs share the responsibility of building nests on open tree branches where they lay a single egg. The incubation periods are presumed longer for larger species, with chicks hatching covered in grey down and being fed regurgitated food by the parents. The family includes species such as the crested treeswift, the grey-rumped treeswift, the whiskered treeswift, and the moustached treeswift.