Abstract A remarkable musk ox (Ovibos moschatus) assemblage was recovered at Cowshead Cave (Picos de Europa Mountains, NW Spain). This find is of special paleobiogeographic relevance since it involves the first occurrence of this species in NW Iberia and extends the boundary of its Eurasian distribution range to the SW. Fossils correspond to at least two individuals: one young male about 20 months old, which includes an extraordinarily well-preserved skull, and one subadult of about 38–44 months. The bone deposit, dated to 34.9 ± 0.4 cal ka BP (MIS 3), accumulated in a karst cave that acted as a natural trap, agreeing with the geomorphology and the good preservation of the remains. Considering that musk ox skulls of young individuals are extremely rare in the Pleistocene record, the detailed comparative study of the skull here presented provides new and relevant information. The skull from Cowshead is larger than modern specimens of similar individual age from Greenland; additionally, some remarkable morphological peculiarities in skull and teeth were identified. One metacarpal of the subadult individual was compared to recent and Pleistocene specimens and was among the largest in the entire sample. Significant differences in morphology and size between fossil and recent metacarpals were detected. Teeth microwear analysis suggests a browsing diet based on twigs and leaves at the time of death, which is consistent with a winter diet. The cold and arid environment inferred from the presence of musk ox is consistent with the paleontological record, since cold-adapted mammals occurred at other contemporary assemblages from NW Iberia.

中文翻译：

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伊比利亚西北部晚更新世 (MIS 3) 记录中首次出现麝牛 Ovibos moschatus：古生物地理和古环境影响

摘要 在 Cowshead Cave (Picos de Europa Mountains, NW Spain) 发现了一种非凡的麝牛 (Ovibos moschatus) 组合。这一发现具有特殊的古生物地理相关性，因为它涉及该物种在西伊比利亚西北部的首次出现，并将其欧亚分布范围的边界扩展到西南部。化石对应于至少两个个体：一个大约 20 个月大的年轻男性，其中包括一个保存得非常完好的头骨，以及一个大约 38-44 个月大的亚成体。骨沉积物的年代为 34.9 ± 0.4 cal ka BP (MIS 3)，堆积在作为天然圈闭的岩溶洞穴中，符合地貌和遗迹的良好保存。考虑到年轻个体的麝牛头骨在更新世记录中极为罕见，这里介绍的头骨的详细比较研究提供了新的相关信息。来自 Cowshead 的头骨比来自格陵兰岛的类似个体年龄的现代标本要大；此外，还确定了颅骨和牙齿的一些显着形态特征。将亚成年个体的一个掌骨与最近和更新世的标本进行了比较，并且是整个样本中最大的一个。检测到化石和最近的掌骨在形态和大小上的显着差异。牙齿微磨损分析表明，在死亡时基于树枝和叶子的浏览饮食，这与冬季饮食一致。从麝牛的存在推断出的寒冷干旱环境与古生物学记录一致，