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| image = | image_width = | image_caption = | parent_authority = Martin ''et al.'', 2012 | authority = Martin ''et al.'', 2012 | type_species = ''Brodavis americanus'' | type_species_authority = Martin ''et al.'', 2012 | subdivision_ranks = Species | subdivision = *''B. americanus'' Martin ''et al.'', 2012 *''B. baileyi'' Martin ''et al.'', 2012 *''B. mongoliensis'' Martin ''et al.'', 2012 *''B. varneri'' (Martin & Cordes-Person, 2007) }} ''Brodavis'' is a genus of freshwater hesperornithiform birds known from the Late Cretaceous (possibly Campanian and Maastrichtian stage) of North America and Asia. It was first described and named by Larry D. Martin, Evgeny N. Kurochkin and Tim T. Tokaryk in 2012 and assigned to a new monogeneric family, Brodavidae. Four species were described and assigned to ''Brodavis''. The type species, ''B. americanus'', is known from the holotype left metatarsal, RSM P 2315.1 which was collected in the Maastrichtian-age Frenchman Formation of Canada. ''B. baileyi'' is known from the holotype left metatarsal, UNSM 50665, which was collected in the Maastrichtian-age Hell Creek Formation of South Dakota, USA (dated to between 66.8 and 66 Ma ago〔Longrich, N.R., Tokaryk, T. and Field, D.J. (2011). "Mass extinction of birds at the Cretaceous–Paleogene (K–Pg) boundary." ''Proceedings of the National Academy of Sciences'', 108(37): 15253-15257. 〕), and ''B. mongoliensis'' is known from the holotype left metatarsal, PIN 4491-8, which was collected in the Maastrichtian-age Nemegt Formation of Mongolia. ''B. varneri'' was originally named as a second species of ''Baptornis'' by James Martin and Amanda Cordes-Person in 2007. It is based on the holotype left tarsometatarsal SDSM 68430 which was collected in the Campanian-age Sharon Springs Formation, lower Pierre Shale of southwestern South Dakota (dated to between 81.5 and 80.5 million years ago.〔Carpenter, K. (2003). "Vertebrate Biostratigraphy of the Smoky Hill Chalk (Niobrara Formation) and the Sharon Springs Member (Pierre Shale)." ''High-Resolution Approaches in Stratigraphic Paleontology'', 21: 421-437. 〕). ''"Baptornis" varneri'' might represent a fourth species of ''Brodavis'' or belong to a separate genus. ''Brodavis'' is considered to be the first freshwater and latest record of the order Hesperornithiformes. Although hesperornithiforms probably lost their flight abilities by the end of the Early Cretaceous, minimal pachyostosis in ''Brodavis'' suggests the possibility of some volant abilities. ==References== 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「Brodavis」の詳細全文を読む スポンサード リンク
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