Abstract A diverse microfauna from the lower shale of the Aguja Formation of West Texas records a rare, early Campanian assemblage of fossil squamates from North America. This assemblage is comprised of scincomorph, anguimorph, and ophidian taxa and is the most inclusive of its kind thus far described from the southern faunal province of Laramidia. Among numerous taxa described herein, three (Hypostylos lehmani gen. et sp. nov., Bothriagenys flectomendax sp. nov., and Hydrargysaurus gladius gen. et sp. nov) pertain to new scincomorphs which dominate the assemblage; however, subordinate anguimorphs are also well-represented. Snakes are represented by a single taxon, aff. Coniophis; a species seemingly ubiquitous throughout most Campanian strata in the southern Western Interior. Comparison among squamate assemblages from similar coastal facies in the upper shale of the Aguja Formation as well as the paracontemporaneous Wahweap and Kaiparowits formations of southern Utah reveals patterns of biogeographic segregation among some lizard species and the presence of two distinct communities. These two ‘southern’ squamate faunas are likely the result of variables involving climate and eustacy which facilitated diversity as well as the development of sub-provincial quarters of endemism during early-middle Campanian time.

中文翻译：

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来自德克萨斯州西部 Aguja 地层（下坎帕阶）的有鳞化石群中的新分类群

摘要 来自西德克萨斯 Aguja 组下部页岩的多样化微型动物群记录了来自北美的罕见的早期坎帕阶化石组合。这种组合由 scincomorph、angumorph 和蛇类类群组成，是迄今为止从南部动物区拉米迪亚省描述的同类中最具包容性的。在本文描述的众多分类群中，三个（Hypostylos lehmani gen. et sp. nov.、Bothriagenys flectomendax sp. nov. 和 Hydrargysaurus Gladius gen. et sp. nov）属于占主导地位的新 scincomorphs；然而，从属的 anguimorphs 也有很好的代表性。蛇由单个分类单元 aff 代表。松果; 一种在西部内陆南部的大多数坎帕尼亚地层中似乎无处不在的物种。来自 Aguja 组上部页岩中类似海岸相以及犹他州南部的准同期 Wahweap 和 Kaiparowits 地层的有鳞类组合之间的比较揭示了一些蜥蜴物种之间的生物地理隔离模式以及两个不同群落的存在。这两个“南部”有鳞动物群很可能是气候和环境变量的结果，这些变量促进了多样性，以及在坎帕尼亚早期中期的地方性地区的发展。