Dacentrurus armatus was the first stegosaur described in the European Upper Jurassic at the end of the 19th century. The description of a second dacentrurine taxon, ‘Miragaia longicollum’, diagnosed from material non-comparable with the D. armatus holotype, has been controversial, and its validity has been challenged. In this study, we describe a new relatively complete stegosaurian postcranial skeleton from the Villar del Arzobispo Formation (Upper Jurassic, Spain). The systematic study of this new specimen and a comprehensive taxonomic assessment of the material not attributed to Stegosaurus from the Upper Jurassic of Europe, reveal high morphological homogeneity and an absence of morphological criteria for distinguishing two dacentrurine taxa. Therefore, ‘Mi. longicollum’ is proposed as a subjective junior synonym of D. armatus. Moreover, a new diagnosis for D. armatus is suggested based on the holotype and referred specimens. As a result, only two stegosaurian species, Stegosaurus stenops and D. armatus, are recognized in Europe during the Late Jurassic. Finally, the species longispinus from the Morrison Formation (Upper Jurassic, USA) is returned to the genus Alcovasaurus.

中文翻译：

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来自西班牙上侏罗统的 Dacentrurus armatus Owen 的新标本，1875 年（鸟臀目：甲龙目）及其与欧洲剑龙多样性的分类学相关性


Dacentrurus armatus 是 19 世纪末在欧洲上侏罗世描述的第一个剑龙类。对第二个 dacentrurine 分类单元“Miragaia longicollum”的描述一直存在争议，该分类单元是根据与 D. armatus 正型标本不可比的材料诊断出来的，其有效性也受到了质疑。在这项研究中，我们描述了来自 Villar del Arzobispo 组（西班牙上侏罗统）的一个新的相对完整的剑龙颅后骨骼。对这个新标本的系统研究以及对欧洲上侏罗统非剑龙的材料的全面分类学评估揭示了高度的形态同质性和缺乏区分两个达森龙类群的形态标准。因此，‘米。 longicollum’ 被提议作为 D. armatus 的主观初级同义词。此外，根据正型标本和参考标本，建议对 D. armatus 进行新的诊断。因此，在侏罗纪晚期的欧洲，只有两种剑龙物种：Stegosaurus stenops 和 D. armatus。最后，来自莫里森组（美国上侏罗统）的长脊龙物种被归回阿尔科瓦龙属。