The Late Jurassic ichthyosaur Nannopterygius is among the poorest known, with the only skeleton, NHMUK PV 46497, on display in the Natural History Museum, London and, therefore, difficult to access. This holotype specimen is here reassessed. The newly obtained data have enabled the identification of several additional specimens of Nannopterygius in museum collections across the UK. Furthermore, all the material of Russian ichthyosaurs previously referred to genera Paraophthalmosaurus and Yasykovia, and considered as junior synonyms of Ophthalmosaurus in the majority of subsequent works, are also reassessed. Both these genera are synonymized with Nannopterygius with preservation of the two from six originally erected species: Nannopterygius saveljeviensis comb. nov. and Nannopterygius yasykovi comb. nov. Additionally, a new species from the Berriasian of Arctic (Svalbard and Franz Josef Land) is proposed. To resolve the phylogenetic relations within Ophthalmosauria, a revised dataset, including 44 taxa and 134 characters, 20 of which are new, was compiled. The results of a phylogenetic analysis places Nannopterygius spp. as sister to Arthropterygius spp. within Ophthalmosaurinae. Thus, the lineage of Nannopterygius was among several ophthalmosaurine lineages that crossed the Jurassic–Cretaceous boundary and, similarly to Arthropterygius, survived the Jurassic–Cretaceous transition at high latitudes.

中文翻译：

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修订Nannopterygius（鱼龙：Ophthalmosauridae）：对“难以接近的”完整型的重新评估消除了分类学上的纠缠，并揭示了分布广泛的晦涩的眼科龙血统

晚侏罗纪鱼龙Nannopterygius是已知最穷的鱼类，唯一的骨架为NHMUK PV 46497，在伦敦自然历史博物馆展出，因此很难接近。在这里重新评估了完整样本。新近获得的数据已使整个英国的博物馆藏品中的楠n目标本得以鉴定。此外，俄罗斯的鱼龙之前称为属的所有材料Paraophthalmosaurus和Yasykovia，且被视为异名大眼鱼龙属中的大多数后续作品，也被重新评估。这两个属都被称为nannopterygius保留了六个最初建立的物种中的两个：Nannopterygius saveljeviensis梳。十一月 和Nannopterygius yasykovi梳子。十一月 此外，还提出了来自北极贝里亚斯人的一个新物种（斯瓦尔巴特群岛和弗朗兹·约瑟夫土地）。为了解决眼睑内的系统发育关系，编制了一个修订的数据集，其中包括44个分类单元和134个字符，其中20个是新的。系统发育分析的结果放置Nannopterygius spp。作为Arthropterygius spp的姐姐。在Ophthalmosaurinae中。因此，Nannopterygius的血统是跨越侏罗纪-白垩纪边界的数种眼松龙血统之一，与节肢动物在高纬度的侏罗纪-白垩纪过渡期幸存下来。