ABSTRACT

The Kibenikhoria and Ernestokokenia local faunas were described in the 1930s by George G. Simpson, who defined them as two chronologically consecutive faunas based on a comparison with the Casamayoran South American Land Mammal Age (SALMA). Later, in the 1980s, the two faunas were respectively the basis of the Itaboraian and Riochican SALMAs, a scheme broadly accepted for more than eight decades. However, a systematic revision of their native ungulates is still lacking. In this contribution, we studied several collections performed in the classical localities of Cañadón Hondo and Bajo Palangana (southeastern South America) and discuss the systematic status of the mammals listed in their faunas. Our results allow us to (1) assert that the beds containing the mammal associations in Cañadón Hondo and Bajo Palangana are located in the upper Las Flores Formation and are essentially contemporaneous; (2) improve the knowledge for Kibenikhoria get and Henricosbornia lophodonta; (3) propose H. waitehor and ?Peripantostylops orehor to be synonymous with H. lophodonta; and (4) recognize Shecenia ctirneru, Seudenius cteronc, and ?Postpithecus as Trigonostylopidae aff. Trigonostylops. The Kibenikhoria and Ernestokokenia faunas have six genera in common; five of them are shared with the lower levels of the Sarmiento Formation. Kibenikhoria get, Isotemnus ctalego, Pliodolops winecage, and Gasternia ctalehor are exclusive taxa of the Kibenikhoria fauna. Here, the Riochican sensu stricto from Marshall is used to include both local faunas, which represents a distinct and more derived fauna than that from the Itaboraí Formation, but with a less advanced evolutionary stage than the lower Sarmiento Formation.

摘要

该Kibenikhoria和Ernestokokenia乔治·辛普森（George G. Simpson）在1930年代描述了当地动物区系，根据与卡萨玛兰南美洲陆地哺乳动物时代（SALMA）的比较，将它们定义为两个按时间顺序连续的动物区系。后来，在1980年代，这两种动物分别是Itaboraian和Riochican SALMAs的基础，该计划已被广泛接受了八十多年。但是，仍缺乏对其有蹄类动物的系统化修改。在这项贡献中，我们研究了在CañadónHondo和Bajo Palangana（南美东南部）的古典地区进行的几个收藏，并讨论了在其动物区系中列出的哺乳动物的系统状态。我们的结果使我们能够（1）断言，包含CañadónHondo和Bajo Palangana的哺乳动物协会的床位于上拉斯弗洛雷斯地层，并且基本上是同期的。（2）提高知识水平Kibenikhoria得到和Henricosbornia lophodonta ; （3）提出ħ。服务员和？Peripantostylops orehor是H的代名词。狼牙; （4）将Shecenia ctirneru，Seudenius cteronc和？Postpithecus识别为Trigonostylopidae aff。三角龙。该Kibenikhoria和Ernestokokenia动物群有共同的六个属; 其中五个与Sarmiento组的较低层共享。Kibenikhoria get，Isotemnus ctalego，Pliodolops winecage和Gasternia ctalehor是Kibenikhoria动物区系的唯一分类群。在这里，来自马歇尔的Riochican sensustricto被用来包括这两种本地动物区系，它们代表了比Itaboraí组的动物区系独特且衍生性更高的动物区系，但是其演化阶段比较低的Sarmiento组要低。