The Eurasian crag martin or just crag martin (Ptyonoprogne rupestris) is a small passerine bird in the swallow family. It is about 14 cm (5.5 in) long...

The crag martins are four species of small passerine birds in the genus Ptyonoprogne of the swallow family. They are the Eurasian crag martin (P. rupestris)...

the Eurasian crag martin and rock martin by its darker underparts, and its white tail spots are significantly smaller than those of the Eurasian crag martin...

of the dusky crag martin, the pale crag martin breeds at a higher altitude. Its range does not overlap there with the Eurasian crag martin, which is found...

dry or mountainous areas are often matte brown above (e.g. sand martin and crag martin). The sexes show limited or no sexual dimorphism, with longer outer...

The purple martin (Progne subis) is a passerine bird in the swallow family Hirundinidae. It is the largest swallow in North America. Despite its name,...

genus, the pale crag martin (P. obsoleta) of north Africa, the dusky crag martin (P. concolor) of southern Asia and the Eurasian crag martin (P. rupestris)...

similar locations on buildings usually in colonies. It is hunted by the Eurasian hobby (Falco subbuteo), and like other birds is affected by internal parasites...

The sand martin (Riparia riparia), also known as the bank swallow (in the Americas), collared sand martin, or common sand martin, is a migratory passerine...

The Caribbean martin or white-bellied martin (Progne dominicensis) is a large swallow. It has at various times been considered alternatively as a race...