The Interatheriinae from the Late Oligocene of Mendoza (Argentina), with comments on some Deseadan Interatheriidae

This contribution discusses the interatheriids from Quebrada Fiera, a Late Oligocene locality in the south of Mendoza Province. In addition, the taxonomic status of the Deseadan interatheres <i>Plagiarthrus clivus</i>, <i>Argyrohyrax proavus</i>, <i>Argyrohyrax proavunculus</i>, ?<i>Argyrohyrax acuticostatus</i>, <i>Progaleopithecus fissurelatus</i>, <i>Progaleopithecus tournoueri</i>, and <i>Notohyrax conicus</i> is discussed. We recognise in Quebrada Fiera <i>A. proavus</i> and <i>Progaleopithecus</i> sp. A possible third taxon is represented by one specimen that shows a combination of features that do not permit accurate assignment. These new remains, in combination with a systematic study of Deseadan interatheres, allow for a better definition of each recognised taxon, extended diagnoses, and clarification of some long-standing taxonomic misconceptions. Indeed, the priority of <i>A. proavus</i> over <i>P. clivus</i> is established, and the latter is proposed as a <i>nomen dubium</i>. Associated deciduous and permanent dentition and some limb bones provide new data on the ontogenetic variation and postcranial morphology of <i>Argyrohyrax</i>. Phylogenetic analysis supports the taxonomic determinations and places <i>A. proavus</i> in a basal position with respect to <i>Archaeophylus</i> or <i>Progaleopithecus</i>. Documented fossil records of <i>Argyrohyrax</i> and <i>Progaleopithecus</i> in Mendoza extend the known range to middle latitudes in central west Argentina; these taxa expand the list of mammals from Quebrada Fiera with Patagonian affinities.

本研究探讨了产自门多萨省南部渐新世晚期遗址菲耶拉峡谷（Quebrada Fiera）的异蹄兽科（Interatheriidae）化石类群。此外，还对德塞达南期异蹄兽类的分类学地位展开讨论，涉及类群包括*Plagiarthrus clivus*、*Argyrohyrax proavus*、*Argyrohyrax proavunculus*、？*Argyrohyrax acuticostatus*、*Progaleopithecus fissurelatus*、*Progaleopithecus tournoueri*与*Notohyrax conicus*。本次研究在菲耶拉峡谷遗址中确认了*A. proavus*与*Progaleopithecus* sp.的存在；另有一件标本因兼具多组特征而无法精确归属，代表一个潜在的第三类群。这批新出土的化石材料结合德塞达南期异蹄兽类的系统学研究，为各已确认类群提供了更精准的界定，完善了类群鉴别特征，并厘清了部分长期存在的分类学误解。本研究确证*A. proavus*的命名优先于*P. clivus*，并将后者定为疑名（nomen dubium）。相关的乳齿与恒齿齿列及部分肢骨材料，为*Argyrohyrax*的个体发育变异与颅后形态学特征提供了新的数据。系统发育分析结果支持本次的分类学判定，并显示*A. proavus*相对于*Archaeophylus*或*Progaleopithecus*处于基部类群位置。门多萨省境内*Argyrohyrax*与*Progaleopithecus*的化石记录，将这两个类群的已知分布范围扩展至阿根廷中西部的中纬度区域；新增的这两个类群丰富了菲耶拉峡谷遗址的哺乳动物化石组合，且均具有巴塔哥尼亚区系亲缘关系。