Abstract SMU 76938 is a nearly complete skeleton of a fossil bony fish, about 1.2 m in total length, housed in Southern Methodist University in Dallas, Texas, USA. It was collected from the Tarrant Formation (middle Cenomanian) of the Upper Cretaceous Eagle Ford Group in Tarrant County, Texas, an area where it was near the East Texas Embayment of the Western Interior Seaway during the Late Cretaceous. Our phylogenetic analysis indicates that it is a pachyrhizodontid crossognathiform fish, and comparisons with previously reported pachyrhizodontids suggest that the fossil fish belongs to a new genus and species within Pachyrhizodontidae, Polcynichthys lloydhilli gen. et sp. nov.. With a fusiform body, a large symmetrical caudal fin, and a mouth with numerous small conical teeth suited for grasping, the new taxon is interpreted to be a fast swimming, open-ocean predator that likely pursued smaller squid, crustaceans, and other fishes. Vertebral growth rings suggest that the individual was possibly about 14 years old at the time of its death, and our vertebra-based theoretical growth model indicates that the species could have reached up to about 1.8 m TL and lived up to 37 years old in age.

中文翻译：

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来自美国德克萨斯州上白垩统鹰福特群塔兰特组（森诺曼阶）的一种新的粗根鱼（Actinopterygii：Teleostei）

摘要 SMU 76938 是一具近乎完整的骨鱼化石骨架，全长约 1.2 m，位于美国德克萨斯州达拉斯的南卫理公会大学。它是从德克萨斯州塔兰特县上白垩纪鹰福特群的塔兰特组（中森诺曼阶）收集的，该地区在晚白垩世期间靠近西部内陆海道的东德克萨斯湾。我们的系统发育分析表明它是一种厚根齿类鱼，与先前报道的厚根齿类鱼的比较表明，这种鱼化石属于厚根鱼科 Polcynichthys lloydhilli gen 中的一个新属和种。等 sp. 11月.. 具有梭形的身体、对称的大尾鳍和带有许多适合抓握的小锥形牙齿的嘴，新分类群被解释为快速游泳，可能会捕食较小的鱿鱼、甲壳类动物和其他鱼类的公海捕食者。椎骨年轮表明该个体在其死亡时可能约为 14 岁，我们基于椎骨的理论生长模型表明该物种可能已达到约 1.8 m TL 并活到 37 岁.