A historic specimen described for the first time revealed important autapomorphic characters, permitting the definition of a new species, Javelinadactylus sagebieli gen. n. et sp. n., which represents the second toothless species from the Javelina Formation, Big Bend National Park of West Texas (United States of America). The remains of J. sagebieli (Azhdarchoidea: Tapejaridae) were found in 1986, but were never properly studied, and its taxonomic affinity remains undefined. The description is based on a partially articulated skull and mandible, which offer information on the anatomy of a single azhdarchoid pterosaur. J. sagebieli exhibit a large nasoantorbital fenestra, a rostral index of medium value and is assigned to the clade Thalassodrominae, a group of tapejarid pterosaurs that were reported exclusively from the Romualdo Formation of Brazil, with only two genera known. Thalassodromines are characterized by a typical cranial configuration with toothless jaws and a high and wide premaxilla bar, formed by sub-parallel or parallel borders. The new specimen described here represents the first record of the Tapejaridae group in the Maastrichtian of North America, and the cranial morphology of the new taxon increase the richest of the diversity of the azhdarchoid pterosaurs during the end of the Late Cretaceous, suggesting that the tapejarids were still diversifying in the Maastrichtian.

一个首次描述的历史标本揭示了重要的自体变形特征，允许定义一个新物种Javelinadactylus sagebieli gen。n. 等 sp. n.，代表来自西德克萨斯州（美利坚合众国）大弯国家公园 Javelina 组的第二个无牙物种。J. sagebieli (Azhdarchoidea: Tapejaridae)的遗骸于 1986 年被发现，但从未得到适当的研究，其分类学亲和力仍未确定。该描述基于部分铰接的头骨和下颌骨，提供了有关单个 azhdarchoid 翼龙的解剖结构的信息。鼠尾草展示了一个大的鼻眶孔，一个中等价值的喙部指数，并被分配到进化枝 Thalassodrominae，这是一组仅从巴西的 Romualdo 组报告的绦虫翼龙，已知只有两个属。Thalassodromines 的特征是典型的颅骨结构，无牙颌和高而宽的前上颌骨，由亚平行或平行边界形成。这里描述的新标本代表了北美马斯特里赫特的绦虫科的第一个记录，新分类群的颅骨形态增加了晚白垩世末期 azhdarchoid 翼龙的最丰富的多样性，表明绦虫仍然在马斯特里赫特地区多样化。