Mosasaurids (Mosasauridae) were specialized marine lizards that evolved and radiated in the Late Cretaceous. Their diversity peaked in the Maastrichtian, with the most diverse faunas known from Morocco. Here we describe a new species of mosasaurid from this fauna. Pluridens serpentis sp. nov. is described based on two complete skulls and referred jaws. It is referred to Pluridens based on the elongate and robust jaws, small teeth, and specialized tooth implantation. Pluridens is referred to Halisaurinae based on the posteriorly expanded premaxilla, long premaxilla-maxilla suture, broad premaxillary facet on the maxilla, closed otic notch, and small, striated, hooked teeth. The orbits are reduced relative to other halisaurines while the snout is robust and flat with a broad, rounded tip. The jaws bear numerous small, hooked, snake-like teeth. Skulls imply lengths of 5–6 m; referred material suggests lengths of ≥9 m. Pluridens’ specialized morphology – especially the contrasting large size and small teeth - suggests a distinct feeding strategy. Small orbits imply that P. serpentis relied on nonvisual cues including touch and chemoreception during foraging, as in modern marine snakes. Numerous neurovascular foramina on the premaxillae are consistent with this idea. The small teeth suggest proportionately small prey. The dentary becomes massive and robust in the largest individuals, suggesting sexual selection and perhaps sexual dimorphism, with the mandibles possibly functioning for combat as in modern beaked whales and lizards. The new mosasaur emphasizes how Maastrichtian mosasaurids were characterized by high species richness, high functional diversity, and high endemism, i.e. geographic specialization. It appears mosasaurids continued diversifying until the end of the Cretaceous, just prior to the K-Pg extinction.

沧龙科（Mosasauridae）是一种特殊的海洋蜥蜴，在白垩纪晚期进化和辐射。它们的多样性在马斯特里赫特地区达到顶峰，拥有摩洛哥已知的最多样化的动物群。在这里，我们从这个动物群中描述了一种新的沧龙科。Pluridens serpentis sp. 十一月 描述基于两个完整的头骨和参考颌骨。基于细长而坚固的颌骨、小牙齿和专门的牙齿植入，它被称为Pluridens。普鲁里登斯基于向后扩张的前上颌骨、长的前上颌骨-上颌骨缝合线、上颌骨上的前上颌骨小面、闭合的耳槽和小的、带条纹的、钩状的牙齿，被称为 Halisaurinae。相对于其他盐龙类，眼眶缩小，而吻部结实而平坦，尖端宽而圆。下颚有许多小的、钩状的、蛇状的牙齿。头骨意味着 5-6 m 的长度；参考资料建议长度≥9 m。Pluridens 的特殊形态——尤其是对比鲜明的大尺寸和小牙齿——表明了一种独特的喂养策略。小轨道意味着P. serpentis依赖于非视觉线索，包括觅食过程中的触觉和化学感受，就像现代海蛇一样。前上颌骨上的许多神经血管孔都与这个想法一致。小牙齿表明猎物比例较小。在体型最大的个体中，牙齿变得巨大而强壮，这表明性别选择和可能的性别二态性，下颌骨可能像现代喙鲸和蜥蜴一样用于战斗。新mosasaur 强调了马斯特里赫特mosasaurids 如何具有高物种丰富度、高功能多样性和高特有性，即地理专业化的特点。沧龙科似乎继续多样化，直到白垩纪末期，即 K-Pg 灭绝之前。