ABSTRACT

The Lophiodontidae are endemic perissodactyls from Europe that flourished during the Eocene. Despite their preponderance in the European fossil record, their exact origin and relationships within the perissodactyls remain unknown due to the rare and fragmentary material in the early Ypresian, the time of their earliest radiation. Lophiaspis maurettei is the oldest and earliest diverging lophiodontid known to date but is unfortunately poorly known. We describe here the results of new excavations of the type locality of Palette. Important new material including complete skulls, mandibles, post-cranial elements and juvenile specimens lead us to revise Lophiaspis maurettei from Palette and other localities and to describe novel morphology for this species. According to an original phylogenetic analysis, based on a revised matrix of dental, cranio-mandibular and postcranial characters, Ls. maurettei is an early diverging lophiodontid morphologically close to Protomoropus and Paleomoropus, two basal chalicotheres, known from Asia and North America, respectively. Our resulting topology does not support the previously proposed inclusion of the lophiodontids within the Ceratomorpha and supports a position within the suborder Ancylopoda, close to some Eomoropidae representatives. These results imply that Ls. maurettei was restricted to Southern Europe during the early Eocene, which would be compatible with an Asian origin for lophiodontids in accordance with the evolutionary history of other perissodactyls and placental mammals.

摘要

phi科（Lophiodontidae）是始于始新世的来自欧洲的地方性过鞭毛基。尽管它们在欧洲化石记录中占主导地位，但由于在伊普尔人早期（即最早的辐射时间）的稀少且碎片化的物质，它们在perissodactyls内的确切来源和关系仍然未知。Lophiaspis maurettei是迄今已知的最古老，最早的发散的phiphitontidid，但不幸的是知之甚少。我们在这里描述Palette类型局部性的新挖掘的结果。重要的新材料，包括完整的头骨，下颌骨，颅后元素和少年标本，使我们修改了Lophiaspis maurettei来自Palette和其他地区，并描述了该物种的新形态。根据原始的系统发育分析，基于牙齿，颅下颌骨和颅后特征Ls的修订矩阵。maurettei是一种形态上较早的裂齿齿类，与Protomoropus和Paleomoropus接近，这是两个基础的直齿类，分别从亚洲和北美洲已知。我们得到的拓扑结构不支持先前提出的将拟南芥中的单齿类目包括在内，并支持在一些畸形螨科代表附近的亚目盲目纲（Ancylopoda）中的一个位置。这些结果暗示Ls。莫雷蒂 在始新世早期被限制在南欧，根据其他过鞭毛基虫和胎盘哺乳动物的进化史，这可能与亚洲起源的蛇纹石兼容。