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Two upper molars of the Chalicotheriidae (Mammalia, Perissodactyla) from the upper Miocene (ca. 10 Ma) Nakali Formation of Nakali, central Kenya, are described. One is identified as M2. The other is very fragmentary and is tentatively referred to the same species as the M2. The M2 specimen is assigned to the subfamily Schizotheriinae in having a crown longer than wide and higher than that of the Chalicotheriinae. It is morphologically similar to upper molars of late Miocene and Plio-Pleistocene species of the Schizotheriinae such as Ancylotherium pentelicum and Ancylotherium hennigi. Metrically, the M2 is within the range of A. pentelicum, resulting an identification as Ancylotherium cf. pentelicum. This result suggests that the fossil record of this genus in Africa dates back to ca. 10 Ma. Previous and present studies suggest that Miocene African Ancylotherium would have been in forest-dominated environments. African and Eurasian fossil records of Ancylotherium suggest that the dispersal of this genus from Eurasia into Africa would have occurred before ca. 10 Ma, although more African fossil records are needed to confirm this. [ABSTRACT FROM AUTHOR]

Pliopithecoids are a diverse group of Miocene catarrhine primates from Eurasia. Their positional behavior is still unknown, and many species are known exclusively from dentognathic remains. Here, we describe a proximal radius (IPS66267) from the late Miocene of Castell de Barberà (Vallès-Penedès Basin, NE Iberian Peninsula) that represents the first postcranial specimen of the pliopithecoid Barberapithecus huerzeleri. A body mass estimate based on the radius is compared with dental estimates, and its morphology is compared with that of extant and fossil anthropoids by qualitative means as well as by landmark-based three-dimensional geometric morphometrics. The estimated body mass of ∼5 kg for IPS66267 closely matches the dental estimates for the (female) holotype, thereby discounting an alternative attribution to the large-bodied hominoid recorded at Castell de Barberà. In multiple features (oval and moderately tilted head with a pronounced lateral lip and a restricted articular area for the capitulum; proximodistally expanded proximal radioulnar joint; and short, robust, and anteroposteriorly compressed neck), the specimen differs from hominoids and resembles instead extant nonateline monkeys and stem catarrhines. The results of the morphometric analysis further indicate that the Barberapithecus proximal radius shows closer similarities with nonsuspensory arboreal cercopithecoids and the dendropithecid Simiolus. From a locomotor viewpoint, the radius of Barberapithecus lacks most of the features functionally related to climbing and/or suspensory behaviors and displays instead a proximal radioulnar joint that would have been particularly stable under pronation. On the other hand, the Barberapithecus radius differs from other stem catarrhines in the less anteroposteriorly compressed and less tilted radial head with a deeper capitular fovea, suggesting a somewhat enhanced mobility at the elbow joint. We conclude that pronograde arboreal quadrupedalism was the main component of the locomotor repertoire of Barberapithecus but that, similar to other crouzeliids, it might have displayed better climbing abilities than pliopithecids. [ABSTRACT FROM AUTHOR]