The first American occurrence of Phoenicopteridae fossil egg and its palaeobiogeographical and palaeoenvironmental implications

ABSTRACTFossil bird eggs from the Pleistocene of the Americas are rare. Previous records include Uruguay, Bermuda, California (USA) and Mexico, including reports of complete fossil eggs from extinct puffin (Fratercula dowi) from California, Tinamou (Tinamidae indet.) from Uruguay, Brown Pelican (Pelecanus occidentalis) from Bermuda and Sandhill Crane (Grus canadensis) from México. The fossil record of flamingos in Mexico is restricted to palaeolakes in Central Mexico, which is very interesting because the current distribution of flamingos in North America is restricted to some areas of the Southeastern United States and Yucatan Peninsula, which are far from palaeontological sites. We report a fossil flamingo egg found during the construction of a new International Airport ‘Felipe Angeles’, Santa Lucía, State of México. This egg is the first Pleistocene fossil egg record for the family Phoenicopteridae, the first fossil egg record of this family in the Americas and the second record of a phoenicopterid fossil egg in the world. We re-identified the fossil eggs described by Martin del Campo in the 1940s, suggesting that they are also flamingo eggs. Using biogeographical and climate niche data for family Phoenicopteridae in North America, we infer the presence of a salinity and shallow palaeolake during the Late Pleistocene, with climatic condition being warmest and wetter than at present.KEYWORDS: Basin of Mexicofossil flamingopalaeoclimatic reconstructionpalaeoecologyPleistocene AcknowledgmentsThe authors thank Secretaria de la Defensa Nacional (SEDENA) for permits to enter the military base. This work has been possible, thanks to M. en C. Felisa Aguilar, president of the Consejo de Paleontología (CONPAL), for the approval of the project ‘Prehistoria y paleoambientes del Noreste de la Cuenca de México’ (401.1S.3-2020/098). We thank Consejo Nacional de Humanidates, Ciencia y Tecnología (CONAHCYT), for the postdoctoral fellowship (I1200/224/2021, MOD.ORD./30/21) awarded to J. Alberto Cruz with the project ‘Reconstrucción paleoambiental y paleoclimática de la localidad paleontológica Aeropuerto Internacional Felipe Ángeles’. We thank Salvamento Arqueológico-INAH team, especially the archeology intern Angel Sabas, for the collection and availability of the fossil egg. Finally, we thank two anonymous reviewers for the comments and recommendations for the publication of this manuscript.Disclosure statementNo potential conflict of interest was reported by the author(s).Additional informationFundingThe work was supported by the Consejo Nacional de Ciencia y Tecnología [I1200/224/2021, MOD.ORD./30/21].