Abstract The Miocene represents a key moment in the South American evolution, since meaningful geographic and climatic processes occurred, promoting the development of several biologic changes. The isolation of South America together with major global and regional climatic changes resulted in an enormous variety of biomes and endemic diversity of flora and fauna, especially of mammals diversity. Most of the best-known continental vertebrate fossil-bearing deposits correspond to the early and late Miocene, existing a deficient knowledge for the middle Miocene, which is poorly understood at high latitudes. This work examines four new middle Miocene fossiliferous localities from a North Patagonian foreland succession, through a multidisciplinary approach that combines stratigraphic and preliminary paleontological analyses within a previously defined high-resolution temporal scheme. Two localities are referred to the lower section of Collon Cura Formation, and were constrained to a range of 14.6–12.75 Ma, whereas the other two localities correspond to the upper section of Collon Cura Formation and were constrained to 12.75–12.05 Ma. A large variety of fossil vertebrates were recognized in the lower section, belonging to Teleostei, Testudinidae, Teiidae, Anura and Mammalia; whereas Teleostei, Testudinidae and Mammalia vertebrates were documented in the upper section. Our results indicate a Colloncuran and younger (e.g., Mayoan) South American Mammals Ages (SALMAs) for the lower and upper sections of Collon Cura Formation, respectively. However, data from this work support the idea of a continuum on the SALMAs sequence for the middle Miocene where overlap, at least partially, both in absolute dates and in the faunal assemblages.

中文翻译：

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阿根廷巴塔哥尼亚西北部的新中新世（Langhian - Serravallian）脊椎动物地点：对高纬度南美陆地哺乳动物年龄序列的贡献

摘要 中新世代表了南美洲演化的关键时刻，因为发生了有意义的地理和气候过程，促进了几种生物变化的发展。南美洲的孤立以及全球和区域的重大气候变化导致了种类繁多的生物群落和地方性动植物多样性，尤其是哺乳动物多样性。大多数最著名的大陆脊椎动物化石矿床对应于早中新世和晚中新世，对中新世的认识不足，在高纬度地区知之甚少。这项工作检查了来自北巴塔哥尼亚前陆序列的四个新的中中新世化石地点，通过多学科方法，在先前定义的高分辨率时间方案中结合地层学和初步古生物学分析。有两个地点是指 Collon Cura 组的下部，被约束在 14.6-12.75 Ma 的范围内，而另外两个地点对应于 Collon Cura 组的上部，被约束在 12.75-12.05 Ma。在下部发现了种类繁多的脊椎动物化石，分别属于硬骨纲、龟科、缨科、无尾目和哺乳纲；而硬骨鱼、龟甲科和哺乳纲脊椎动物则记录在上半部分。我们的结果表明，Collon Cura 组的下部和上部分别是 Colloncuran 和更年轻的（例如 Mayoan）南美洲哺乳动物时代 (SALMA)。然而，