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''Andalgalornis'' was a genus of flightless predatory birds of the family Phorusrhacidae (often called "terror birds") that lived in Argentina. The type and only species is ''A. steulleti''. ''Andalgalornis'' is known from an incomplete skeleton and some single bones found from sites in the Entre Ríos and Catamarca Provinces of northeast and northwest Argentina. The fossils were uncovered from the Miocene to Early Pliocene Andalgala Formation. ==Description== ''Andalgalornis'' stood around one and a half meters tall. The subfamily to which the genus belonged, the Patagornithinae, contained species that were of quite slender build; it looked much like the larger phorusrhacid ''Phorusrhacos'', but it was more elegant and smaller and had a proportionally higher beak, the most massive in proportion to body size of all phorusrhacids. A recent analysis of CT scans of the skull of ''Andalgalornis'' suggests that the beak was strong dorsoventrally (in the vertical plane) but relatively weak mediolaterally on either side. The beak's weakness suggests that the bird could not have taken down large prey, but consumed smaller, more easily manageable and less risky prey. However, the beak's dorsoventral strength may have enabled ''Andalgalornis'' to quickly strike down on its prey in a repeated attack-and-retreat hunting strategy. A study of its neck vertebrae showed that they were built for striking. ==References== * Alvarenga, Herculano M. F. & Höfling, Elizabeth (2003): Systematic revision of the Phorusrhacidae (Aves: Ralliformes). ''Papéis Avulsos de Zoologia'' 43(4): 55-91 (PDF fulltext ) * Kraglievich, Lucas (1931): Contribución al conocimiento de las aves fósiles de la época araucoentrerriana. ''Physis'' 10: 304-315. (in Spanish ) * Patterson, B. & Kraglievich, Lucas (1960): Sistemática y nomenclatura de las aves fororracoideas del Plioceno Argentino. ''Publicacion del Museo Municipal Ciencias Naturales y Tradicionales de Mar del Plata'' 1: 1-51. (in Spanish ) 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「Andalgalornis」の詳細全文を読む スポンサード リンク
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