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''Aegialornis''〔 Etymology: ''Aegialornis'', "beach bird", from Ancient Greek ''aegial-'', "beach" + ''ornis'', "bird". The first bones were recovered from sediments of a former lagoon at Quercy, France.〕 is a genus of prehistoric apodiform bird. It formed a distinct family Aegialornithidae and was in some ways intermediate between modern swifts and owlet-nightjars, lacking the more extreme adaptations to an aerial lifestyle that swifts show today, but already having sickle-shaped wings like them. They do not appear to be a direct ancestor of modern swifts, however, but rather a group that retained an overall basal morphology. Altogether, they were not too dissimilar to modern treeswifts. Fossils of ''Aegialornis'' have been found in Middle to Late Eocene deposits of Germany and France. An Early Eocene record from the Nanjemoy Formation of Virginia, USA (USNM 496384) is very doubtful, as apodiform birds seem not to have occurred there until after the Eocene. This bone might more properly belong to the Parvicuculidae (Mayr & Mourer-Chauviré 2005). The taxonomy of the species is quite convoluted, with both the smaller ''A. germanicus'' and the larger ''A. leenhardti'' being sometimes considered junior synonyms of ''A. gallicus'', which in turn is sometimes erroneously assumed to be identical to ''Cypselavus gallicus''. Similarly, ''A. broweri'' is occasionally considered to be based on small individuals of ''A. wetmorei'', and these latter two taxa were recently separated as genus ''Mesogiornis'' (Mlíkovský, 2002); this does not appear to have found general acceptance however. The presumed species ''Aegialornis szarskii'' is now placed in ''Scaniacypselus''. It is not quite certain which genera apart from the present one should be included in the Aegialornithidae. ''Primapus'' belongs either here or is a basal true swift, and ''Cypselavus'' is either an aegialornithid or a treeswift. The latter group is sometimes controversially included in the Aegialornithidae, as are the Jungornithidae, another prehistoric apodiform family that was somewhat intermediate between treeswifts and hummingbirds. ==References== * Mayr, Gerald & Mourer-Chauviré: A specimen of ''Parvicuculus'' Harrison & Walker 1977 (Aves: Parvicuculidae) from the early Eocene of France. ''Bull. B. O. C.'' 125(4): 299-304. (PDF fulltext ) * Mlíkovský, Jirí (2002): ''Cenozoic Birds of the World, Part 1: Europe''. Ninox Press, Prague. (PDF fulltext ). ==Footnotes== 〔 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「Aegialornis」の詳細全文を読む スポンサード リンク
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