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The Eurasian crag martin or just crag martin (''Ptyonoprogne rupestris'') is a small passerine bird in the swallow family. It is about long with ash-brown upperparts and paler underparts, and a short, square tail that has distinctive white patches on most of its feathers. It breeds in the mountains of southern Europe, northwestern Africa and southern Asia. It can be confused with the three other species in its genus, but is larger than both, with brighter tail spots and different plumage tone. Many European birds are resident, but some northern populations and most Asian breeders are migratory, wintering in northern Africa, the Middle East or India. The Eurasian crag martin builds a nest adherent to the rock under a cliff overhang or increasingly onto a man-made structure. It makes a neat half-cup mud nest with an inner soft lining of feathers and dry grass. Nests are often solitary, although a few pairs may breed relatively close together at good locations. Two to five brown-blotched white eggs are incubated mainly by the female, and both parents feed the chicks. This species does not form large breeding colonies, but is gregarious outside the breeding season. It feeds on a wide variety of insects that are caught in its beak as the martin flies near to cliff faces or over streams and alpine meadows. Adults and young may be hunted and eaten by birds of prey or corvids, and this species is a host of blood-sucking mites. With its very large and expanding range and large population there are no significant conservation concerns. This bird is closely related to the other three crag martins which share its genus, and has sometimes been considered to be the same species as one or both, although it appears that there are areas where two species' ranges overlap without hybridisation occurring. All three ''Ptyonoprogne'' crag martins are quite similar in behaviour to other Old World swallows that build mud nests, and are sometimes subsumed into the larger genus ''Hirundo'', but this approach leads to inconsistencies in classifying other genera, particularly the house martins. == Taxonomy == The Eurasian crag martin was formally described as ''Hirundo rupestris'' by Italian naturalist Giovanni Antonio Scopoli in 1769〔Scopoli (1769) p. 172〕 and was moved to the new genus ''Ptyonoprogne'' by German ornithologist Heinrich Gustav Reichenbach in 1850.〔Reichenbach (1850) plate LXXXVII figure 6〕 Its nearest relatives are the three other members of the genus, the pale crag martin, ''P. obsoleta'', the rock martin, ''P. fuligula'', and the dusky crag martin, ''P. concolor''.〔Turner (1989) pp. 160–164〕 The genus name is derived from the Greek ''ptuon'' (φτυον), "a fan", referring to the shape of the opened tail, and Procne (Πρόκνη), a mythological girl who was turned into a swallow. The specific ''rupestris'' means "of rocks", from the Latin ''rupes'' "rock". There are no generally recognised subspecies. Two races, Central Asian ''P. r. centralasica'' and ''P. r. theresae'' in the Atlas Mountains of Morocco, have been proposed, but the slight differences in size and colour show no consistent geographical pattern.〔Turner (1989) pp. 158–160〕 Fossils of this species have been found in Late Pleistocene deposits in Bulgaria,〔Boev Zlatozar. (2001). "(Late Pleistocene birds from the Kozarnika Cave (Montana District; NW Bulgaria) )" in Delchev P., Shanov S., Benderev A. (Eds) ''Proceedings of the First national Conference on Environment and Cultural Heritage in Karst. Sofia 10–11.11.2000. Volume 1'' 113–128.〕 and in central France in layers dated at 242,000 to 301,000 years ago. The four ''Ptyonoprogne'' species are members of the swallow family of birds, and are placed in the Hirundininae subfamily, which comprises all swallows and martins except the very distinctive river martins. DNA studies suggest that there are three major groupings within the Hirundininae, broadly correlating with the type of nest built. The groups are the "core martins" including burrowing species like the sand martin, the "nest-adopters", which are birds like the tree swallow that utilise natural cavities, and the "mud nest builders". The ''Ptyonoprogne'' species construct an open mud nest and therefore belong to the last group; ''Hirundo'' species also build open nests, ''Delichon'' house martins have a closed nest, and the ''Cecropis'' and ''Petrochelidon'' swallows have retort-like closed nests with an entrance tunnel. ''Ptyonoprogne'' is closely related to the larger swallow genus ''Hirundo'' into which it is often subsumed, but a DNA analysis showed that an enlarged ''Hirundo'' genus should logically contain all the mud-builder genera, including the ''Delichon'' house martins, a practice which few authorities follow. Although the nests of the ''Ptyonoprogne'' crag martins resembles those of typical ''Hirundo'' species like the barn swallow, the research showed that if ''Delichon'', ''Cecropis'' and ''Petrochelidon'' are split from ''Hirundo'', ''Ptyonoprogne'' should also be treated as a separate genus.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Eurasian crag martin」の詳細全文を読む スポンサード リンク
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