The systematic status and evolutionary significance of the robust tuco-tuco Ctenomys latidens from the Pleistocene of central Argentina

We conduct a systematic review of the extinct robust species of Ctenomys from the Early-Middle Pleistocene of central Argentina to assess the systematic status of †Ctenomys latidens. Based on qualitative comparisons and geometric morphometric evidence, †Ctenomys latidens is identified as a well-supported species, clearly distinguishable from †Ctenomys magnus and †Ctenomys kraglievichi. We propose †Ctenomys intermedius Rusconi, 1931a, and †Ctenomys dasseni Rusconi, 1931a as junior synonyms of †C. latidens. Accordingly, †Ctenomys latidens is recorded in the late Ensenadan age (late Early to early Middle Pleistocene) of Buenos Aires Province in central Argentina. Additionally, we suggest upgrading †Ctenomys intermedius tandilensis Rusconi, 1931a, and †Ctenomys latidens orthognathus Rusconi, 1931a to full species status. Finally, we demonstrate that the name †Plateomys scindens cannot be applied to the Early Pliocene Octodontidae currently recognised as †Pseudoplataeomys formosus, as that taxon is a potential junior synonym of †Ctenomys latidens.本研究针对阿根廷中部早-中更新世已灭绝的强壮栉鼠属（Ctenomys）物种开展系统性分类学综述，以评估宽齿栉鼠（†Ctenomys latidens）的分类学地位。基于定性比较与几何形态测量学证据，宽齿栉鼠被确立为一个支持度良好的物种，可与巨栉鼠（†Ctenomys magnus）和克拉格栉鼠（†Ctenomys kraglievichi）明确区分。本研究将1931年Rusconi发表的中间栉鼠（†Ctenomys intermedius）与达森栉鼠（†Ctenomys dasseni）确立为宽齿栉鼠的次异名。据此，宽齿栉鼠的化石记录见于阿根廷中部布宜诺斯艾利斯省的恩塞纳达晚期（早更新世晚期至中更新世早期）地层。此外，本研究提议将1931年Rusconi发表的坦迪尔中间栉鼠（†Ctenomys intermedius tandilensis）与正颌宽齿栉鼠（†Ctenomys latidens orthognathus）提升为独立物种。最后，本研究证实，†Plateomys scindens这一名称无法用于当前被定为美丽假扁鼠（†Pseudoplataeomys formosus）的上新世早期八齿鼠科物种，因为该类群实为宽齿栉鼠的潜在次异名。