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Estudios Geologicos 2011
Reconsideration of the systematics of the Early Pleistocene Cervavitus (Cervidae, Artiodactyla, Mammalia)Keywords: Cervavitus , Cervidae , Artiodactyla , systematics , Neogene , Early Pleistocene , paleoenvironment , Cervivatus , Cervidae , Artiodactyla , Sistematica , Neógeno Abstract: Cervavitus were usually found from the Late Miocene and Pliocene deposits in East Europe, Middle Asia and North China, but they were found recently in many Early Pleistocene localities in southern China. The latter resulted in the discussion of their systematic status between Cervavitus and Cervus. Here we show the Early Pleistocene forms from southern China are morphometrically more similar to northern China Cervavitus species, and the cladistic analysis shows that the southern China forms are closer to classic Cervavitus species than Cervus and that also proves their systematic status in Cervavitus rather than in Cervus. Cervavitus originated in Moldovan forests of East Europe in the late Vallesian (MN10) from a brachyodont and holometacarpal ancestor with two/three-tined antlers and Palaeomeryx fold and evolved into C. novorossiae. It dispersed into West Europe forests in the earliest Turolian and further west to France in the Ruscinian. It dispersed into northern China forests in the early Turolian and represented by C. shanxius. The great quantity of C. shanxius specimens with brachyodont teeth and complete lateral metacarpals implies the arid Loess Plateau of today was a humid forested region in the Late Miocene. C. shanxius migrated southwards in the Plio-Pleistocene probably due to the drying environment in northern China with uplifting of Himalayas and evolved into C. ultimus and C. fenqii, which survived in southern China until the Early Pleistocene (MNQ18). La revisión sistemática de Cervivatus sugiere que deriva del principal clado de los cérvidos posteriores a los muntiacinos, e implica que Procervulinae, Dicrocerinae y la primeras formas de Munticiacinae serían holometacarpales, como también lo es Cervivatus, originario en los bosques de Moldavia (Europa del Este) durante el Vallesiense final (MN 10), a partir de un antecesor braquiodonto y holometacarpal, con astas con dos o tres candiles y pliegue paleomerícido, y que da lugar a C. novorossiae. Este se dispersó a Europa occidental durante el comienzo del Turoliense, y más al oeste a Francia durante el Rusciniense. Su dispersión en los bosques del norte de China se produjo también a comienzos del Turoliense, estando representado por C. shanxius. Existe una gran cantidad de ejemplares de C. shanxius con metápodos laterales completos, que debían ser útiles para equilibrar el cuerpo en las ramas de los árboles. Las áridas mesetas loésicas actuales fueron bosques húmedos durante el Mioceno final. C. shanxius emigró hacia el sur durante el Plio-Pleistoceno probablemente debido al ambiente más
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