The hippoboscid or louse flies, Pseudolynchia and Lynchia spp, are winged versions of the keds. They infest many song birds, raptors, and pigeons. The pigeon fly, P canariensis, is an important parasite of domestic pigeons throughout the tropical and subtropical regions of the world. It is found throughout the southern USA and northward along the Atlantic coast to New England. These dark brown flies have long wings (6.5–7.5 mm) and are able to fly swiftly from the host.
Hippoboscid flies move about quickly on their avian hosts and bite and suck blood from parts that are not well feathered. They may serve as intermediate hosts for many avian blood protozoans of the genus Haemoproteus. Pigeon flies readily attack people who handle adult birds; the bite is said to be as painful as a bee sting, and its effects may persist for ≥5 days.