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The dusky crag martin (''Ptyonoprogne concolor'') is a small passerine bird in the swallow family. It is about 13 cm (5.1 in) long with a broad body and wings, and a short square tail that has small white patches near the tips of most of its feathers. This martin has sooty-brown upperparts and slightly paler underparts. The two subspecies are resident breeding birds in South Asia from the Indian subcontinent to southwestern China and the northern parts of Thailand, Vietnam and Laos. This martin nests under a cliff overhang or on a man-made structure, building a neat half-cup mud nest with a soft lining. Both adults incubate the two to four eggs and feed the chicks. This species does not form large breeding colonies, but it is more gregarious outside the breeding season. It feeds an a wide variety of insects that are caught as the martin flies near to cliff faces. It may be hunted by large bats as well as birds of prey, but its extensive and expanding range and large population mean that there are no significant conservation concerns. ==Taxonomy== The dusky crag martin was formally described by in 1832 as ''Hirundo concolor '' by British soldier and ornithologist William Henry Sykes. It 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 rock martin ''P. fuligula'', the pale crag martin, ''P. obsoleta'', and the Eurasian crag martin ''P. rupestris''.〔Turner (1989) pp. 158–164〕 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 ''concolor'' is from Latin, ''con'' "together", and ''color'' "colour" and refers to the bird's uniform colouration. The four ''Ptyonoprogne'' species are members of the swallow family of birds, and are classed as members of 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 latter 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. The genus ''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 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 be also considered as a separate genus.〔 In Pakistan, the breeding range of the dusky crag martin overlaps that of the subspecies ''P. f. peloplasta'' of pale crag martin, but that species breeds much higher in the mountains. This altitudinal separation means that it is not known whether the two closely related martins could hybridise, which would cast doubts as to whether they were distinct species.〔 Dusky crag martins from Burma and Thailand have been described as a separate darker subspecies, ''P. c. sintaungensis'' (originally ''Krimnochelidon concolor sintaungensis'', Baker, 1832), but it is not clear that the difference is greater than that between individual martins of the nominate subspecies.〔Turner (1989) pp. 163–164〕 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「Dusky crag martin」の詳細全文を読む スポンサード リンク
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