New material and the phylogenetic position of Cayaoa bruneti Tonni, an early Miocene anseriform (Aves) from Patagonia, Argentina

NORIEGA, JORGE I.; TAMBUSSI, CLAUDIA P.; COZZUOL, MARIO A.

Neues Jardbuch Geologie und Palaontologie Abhandlungen

E. Schweizerbart'sche Verlagsbuchhandlung

Lugar: Stuttgart; Año: 2008 vol. 249 p. 271 - 280

Cayaoa bruneti TONNI, 1979 is an early Neogene anseriform exhumed from marine sediments of the lower levels of the Gaiman Formation (“Patagoniano”, Leonian Marine Stage, Chubut, Argentina). It was originally based on a partial tarsometatarsus that was not assigned to subfamily or tribe. We re-examine the holotype and study new tarsometatarsi, and previously undescribed skeletal elements including partial femora, tibiotarsi, partial humeri and carpometacarpi. Cayaoa bruneti was a strictly foot-propelled diving bird that exhibited an extreme reduction of the fore-limb, being probably the earliest recorded flightless duck. Similarly reduced wings are found in the distantly related anseriform Cnemiornis OWEN, 1866 of subrecent deposits of New Zealand, the fore-limb, being probably the earliest recorded flightless duck. Similarly reduced wings are found in the distantly related anseriform Cnemiornis OWEN, 1866 of subrecent deposits of New Zealand, the fore-limb, being probably the earliest recorded flightless duck. Similarly reduced wings are found in the distantly related anseriform Cnemiornis OWEN, 1866 of subrecent deposits of New Zealand, was a strictly foot-propelled diving bird that exhibited an extreme reduction of the fore-limb, being probably the earliest recorded flightless duck. Similarly reduced wings are found in the distantly related anseriform Cnemiornis OWEN, 1866 of subrecent deposits of New Zealand, Cnemiornis OWEN, 1866 of subrecent deposits of New Zealand, Cnemiornis OWEN, 1866 of subrecent deposits of New Zealand, Chendytes MILLER, 1925 of the Pleistocene of California, and the moa-nalos of the Late Quaternary of Hawaii. of Hawaii. of Hawaii. MILLER, 1925 of the Pleistocene of California, and the moa-nalos of the Late Quaternary of Hawaii.