ABSTRACT

The middle and late Eocene perissodactyl fossil record of western Iberia is characterized by an endemic fauna, which is clearly different from those of northeastern Iberia and other areas of the European archipelago. In this work, we describe three endemic equoid taxa belonging to the family Palaeotheriidae. Two come from the late Eocene site of Zambrana (Miranda-Treviño Basin, Araba/Álava, Spain) and correspond to new species: Leptolophus cuestai, sp. nov., and Leptolophus franzeni, sp. nov. Leptolophus cuestai, sp. nov. is the largest species of Leptolophus and exhibits thick coronal cementum and a very high hypsodonty index, unusual for an Eocene equoid. Leptolophus franzeni, sp. nov. is described from a cranium which includes the canines, which are otherwise unknown in Leptolophus. The third taxon, from the late middle Eocene site of Mazaterón (Almazán Basin, Soria, Spain), described provisionally as Leptolophus sp., could be another new Iberian species. The Iberian taxa are characterized by having: more hypsodont, lophodont and heterodont dentition than the Central European Leptolophus taxa (L. stehlini, L. nouleti and L. magnus); thicker styles and stylar ribs in the upper jugal teeth; and thicker coronal cementum. The precocious development of coronal cementum and the high hypsodonty index could be related to different foraging conditions (tougher vegetation, more open or drier habitats with a higher consumption of grit in the diet) inhabited by the Iberian Leptolophus species with respect to their Central European contemporaries.

http://zoobank.org/urn:lsid:zoobank.org:pub:03F87D46-2320-41D2-AE08-333866F005AD

摘要

伊比利亚西部始新世中晚期的奇蹄类动物化石记录以特有动物群为特征，与伊比利亚东北部和欧洲群岛其他地区的动物群明显不同。在这项工作中，我们描述了属于古兽科的三个地方性马科动物分类群。两个来自 Zambrana 的晚始新世遗址（Miranda-Treviño Basin，Araba/Álava，西班牙），对应于新物种：Leptolophus cuestai，sp。11 月，和Leptolophus franzeni，sp。十一月 Leptolophus cuestai，SP。十一月 是最大的钩端虫属，具有厚的冠状牙骨质和非常高的牙周病指数，这对于始新世马蹄莲来说是不寻常的。法国钩虱，sp。十一月 是从头骨中描述的，其中包括犬齿，否则在钩端螺旋体中是未知的。来自 Mazaterón（阿尔马赞盆地，索里亚，西班牙）中始新世晚期的第三个分类群，临时描述为Leptolophus sp.，可能是另一个新的伊比利亚物种。伊比利亚分类群的特点是：比中欧钩端动物分类群（L. stehlini、L. nouleti和L. magnus); 上颌牙有较厚的样式和花柱肋；和较厚的冠状牙骨质。冠状牙骨质的早熟发育和高牙骨质指数可能与伊比利亚钩端虫物种相对于中欧同时代的不同觅食条件（更坚固的植被、更开放或干燥的栖息地以及更高的砂砾消耗）有关.

http://zoobank.org/urn:lsid:zoobank.org:pub:03F87D46-2320-41D2-AE08-333866F005AD