This paper provides a detailed description and the functional anatomy of the forelimb of an early Oligocene genet-sized arctoid carnivoran, Amphicynodon leptorhynchus, to infer its probable lifestyle. This work represents the first insights into the functional anatomy of the postcranial skeleton and palaeoecology of an emblematic member of the first radiation of arctoid carnivorans, the poorly known Amphicynodontidae, a group very likely related to bears. So far, the Amphicynodontidae have only been studied on the basis of their cranial and dental remains. The fossil site of Itardies (MP23, lower Oligocene), in the Quercy Phosphorites (France), have yielded hundreds of postcranial remains attributed to Am. leptorhynchus, allowing a complete analysis of its locomotor behaviour in comparison to a large sample of extant carnivorans showing diverse lifestyles. The anatomy of the forelimb of Am. leptorhynchus indicates well-developed climbing skills and grasping abilities. Thus, this early arctoid was probably living mostly in trees, moving on the ground basically for foraging as observed in small modern climbing carnivorans such as the red panda or the kinkajou, although some other climbing carnivorans can also live in rocky areas.

本文提供了详细的描述和早期渐新世基因大小的弧形食肉动物Amphophynodon leptorhynchus的前肢，以推断其可能的生活方式。这项工作代表了对弧后食肉动物首次辐射的象征成员，即鲜为人知的两栖昆虫科（Amphicynodontidae）的颅后骨骼的功能解剖学和古生态学的首次见解，该组很可能与熊有关。迄今为止，仅基于其颅骨和牙齿残骸研究了两栖昆虫科。位于Quercy Phosphorites（法国）的Itardies（MP23，下渐新世）的化石遗址已产生了成百上千个归因于Am的颅后遗骸。细支气管，与大量现存食肉动物样本（显示多种生活方式）相比，可以对其运动行为进行完整的分析。Am的前肢的解剖。轻支气管表示发达的攀岩技能和抓地能力。因此，这种早期的弓形虫可能主要生活在树木中，基本上是在地面上觅食，这在小型现代攀缘食肉动物（如小熊猫或kinkajou）中观察到，尽管其他一些攀缘食肉动物也可以生活在多岩石的地区。