Three new chasmosaurines from the Kirtland Formation (∼75.0 - 73.4 Ma), New Mexico, form morphological and stratigraphic intermediates between Pentaceratops (∼74.7 - 75Ma, Fruitland Formation, New Mexico) and Anchiceratops (∼72 - 71Ma, Horseshoe Canyon Formation, Alberta). The new specimens exhibit gradual enclosure of the parietal embayment that characterizes Pentaceratops, providing support for the phylogenetic hypothesis that Pentaceratops and Anchiceratops are closely related. This stepwise change of morphologic characters observed in chasmosaurine taxa that do not overlap stratigraphically is supportive of evolution by anagenesis. Recently published hypotheses that place Pentaceratops and Anchiceratops into separate clades are not supported. This phylogenetic relationship demonstrates unrestricted movement of large-bodied taxa between hitherto purported northern and southern provinces in the Late Campanian, weakening support for the hypothesis of extreme faunal provincialism in the Late Cretaceous Western Interior.

中文翻译：

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Chasmosaurine ceratopsid恐龙的过渡演化形式和地层趋势：来自新墨西哥州坎帕尼亚人的证据

（ - 73.4麻~75.0），新墨西哥，形式形态和地层之间的中间体从柯特兰形成的三大新chasmosaurines五角龙属（~74.7 - 75MA，弗鲁特兰组，新墨西哥州）和准角龙（〜72 - 71Ma，马蹄峡谷组，阿尔伯塔）。新的标本展现出逐渐形成的包围着五角锥特征的顶壁，从而为五角锥和拟南芥密切相关的系统发育假说提供了支持。这种在金龙舌兰类群中观察到的形态特征的逐步变化，这些变化在地层上不重叠，这支持了成因作用的演化。最近发表的关于放置五足类动物的假说和不支持成单独的进化枝的拟南芥。这种系统发育关系表明，迄今为止，坎帕尼亚晚期据称北部和南部省份之间的大类群活动不受限制，削弱了对晚白垩世西部内陆极端动物区系主义假说的支持。