Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. The Square-tailed Saw-wing (Psalidoprocne nitens), also known as the Square-tailed Rough-winged Swallow is a species of bird in the Hirundinidae family. It is found in Angola, Cameroon, Central African Republic, Republic of the Congo, Democratic Republic of the Congo, Ivory Coast, Equatorial Guinea, Gabon, Ghana, Guinea, Liberia, Nigeria, and Sierra Leone. The swallows and martins are a group of passerine birds in the family Hirundinidae which are characterised by their adaptation to aerial feeding. Swallow is used colloquially in Europe as a synonym for the Barn Swallow.