Abstract New findings of Mawsonia from the Juro-Cretaceous Tacuarembo Formation (Uruguay) are presented. The new materials have taphonomic and anatomic significance, considering the biofabric and state of preservation of most of the bones. The most complete specimen studied is represented by several cranial and postcranial remains found in spatial association, including skull roof, cheek bones and opercula, neurocranium, palate, lower jaw, branchial and hyoid apparatuses; and also part of the shoulder and pelvic girdles. The present record is also complemented through the finding of several isolated bones from other individuals. General morphology of the bones, postparietal shield configuration and external ornamentation of dermic bones, allow to refer all the specimens to the species Mawsonia gigas. It is considered that the most complete specimen studied in this work constitutes one of the anatomically most informative records referable to this species, and to the genus, considering the following arguments: The presence of complete bones scarcely represented in previous records due to its delicate configuration, and the fact that all the remains are three-dimensionally preserved (being completely released from their sedimentary matrix). The new information provided by the comparative analyses is used for the following purposes: Bring a critical anatomical description, complement the diagnosis of the genus, and discuss previous taxonomical and ontogenetic hypotheses. The comparative analyses support previous taxonomic proposals, regarding the existence of morphological, size and ornamental variabilities, which as a whole characterize M. gigas and place it as the only recognizable species referable to this genus in South America.

中文翻译：

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来自晚侏罗世 – 乌拉圭早白垩世腔棘鱼 Mawsonia Woodward（Actinistia，Latimerioidei）的新发现：新的解剖学和分类学考虑以及对该属的修正诊断

摘要 介绍了来自 Juro-白垩纪 Tacuarembo 组（乌拉圭）的 Mawsonia 的新发现。考虑到大多数骨骼的生物结构和保存状态，新材料具有埋藏学和解剖学意义。研究的最完整的标本是在空间关联中发现的几个颅骨和颅后遗骸，包括颅顶、颧骨和鳃盖、神经颅骨、上颚、下颌、鳃和舌骨；以及肩部和骨盆带的一部分。目前的记录也通过从其他人身上发现的几块孤立的骨头得到了补充。骨骼的一般形态、顶骨后盾构型和真皮骨骼的外部装饰，允许将所有标本归类为 Mawsonia gigas。考虑到以下论点，这项工作中研究的最完整的标本构成了该物种和该属的解剖学上最翔实的记录之一：由于其精致的构造，以前的记录中几乎没有完整骨骼的存在，以及所有遗迹都得到三维保存（完全从其沉积基质中释放出来）的事实。比较分析提供的新信息用于以下目的：提供关键的解剖学描述，补充属的诊断，并讨论以前的分类学和个体遗传学假设。比较分析支持先前的分类学建议，关于形态、大小和观赏变异的存在，作为一个整体表征 M.