The white-chinned swift (Cypseloides cryptus) is a species of swift in the family Apodidae. It is found from Mexico south through most Central America countries into South America as far south as Peru and east as far as Suriname. Taxonomy and systematics The white-chinned swift is monotypic. Some authors consider it and the white-fronted swift (Cypseloides storeri) to form a superspecies. Others consider it more closely related to the sooty swift (C. fumigatus) and Rothschild's swift (C. rothschildi) or that all three of them are a single species. Description The white-chinned swift is about long and weighs about . The sexes are alike. They have a dark brown crown and cheeks, a short white streak above the eye, a white chin, and a dark brown throat. Their back and rump are blackish brown and the wings and tail slightly darker. Their undersides are paler than the back and rump and the underside of the wing is paler than the upper side. Distribution and habitat The white-chinned swift is widely but very patchily distributed. It has been confirmed to nest only in Costa Rica and at one location in northern Brazil. There are sight records in Mexico and very few confirmed records in Belize, Guatemala, Honduras, Nicaragua, and Panama. There are somewhat more records in Colombia, Ecuador, Guyana, Peru, Suriname, and Venezuela. It has occurred as a vagrant in French Guiana and there is at least one sight record in Bolivia. The white-chinned swift has mostly been recorded over evergreen montane and lowland forests, but also occurs at pastures and young secondary forest. In elevation it ranges from sea level to . Behavior Migration Whether the white-chinned swift is resident or migratory at any of its locations is unknown. Feeding Like all swifts, the white-chinned is an aerial insectivore. Its prey includes Hymenoptera, Coleoptera, Diptera, Lepidoptera, Hemiptera, and Homoptera. It usually forages in flocks, often with other swifts. Breeding Most information about the white-chinned swift's breeding is from Costa Rica. There it lays eggs from early May into early June. It builds a nest of moss, liverworts, and mud on a rock wall near or behind a waterfall. It is usually in a crevice or under a small overhang and often has overhanging vegetation. The clutch size is one egg. The incubation period is about 30 days and fledging occurs 55 to 58 days after hatch. At the one Brazilian nesting