Black Saw-wing

The black rough-winged swallow is a small swallow at 13–15 cm length with a forked tail. Its plumage is blue-glossed black. Sexes are similar, but the female has shorter outer tail feathers, and less obvious wing serrations. Juveniles are brown with little gloss, and have short tails. There are many subspecies of this swallow, which some authorities may split into different species. In particular, four northeastern races, including nominate P. p.