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We report a new genus and species of herbivorous mammal, Pahelia mysteriosa, from the early Eocene Cambay Shale Formation, Tadkeshwar Lignite Mine, Gujarat, India. The new taxon, approximately the size of a small phenacodontid (e.g. Ectocion parvus), is represented by three mandibular fragments, the most complete of which documents nearly the entire symphysis and mandibular body plus P3–M3. Pahelia has incipiently selenolophodont molars with strong exodaenodonty, absent paraconids, weak but distinct entolophids, and prominent ectostylids. Molar size increases distally, but M3 does not develop a prominent third lobe. Premolars are simple, with prominent protoconids and short talonids but little development of other trigonid cusps. The mandibular symphysis is strongly fused, and there is an enlarged alveolus for an anterior tooth. The combination of features present in the new taxon does not closely match that of any known mammal, but there are some similarities to a diversity of ungulates from Africa, Asia, Europe and North America. Preserved morphology is insufficient to assess the affinities of the new taxon with confidence, but a link to Quettacyonidae, also endemic to the Indian subcontinent, is morphologically and biogeographically plausible. If this scenario is correct, it suggests that P. mysteriosa could be a part of the endemic mammalian fauna of India prior to its initial faunal contact with Asia. [ABSTRACT FROM AUTHOR]

ABSTRACT The earliest euprimates to arrive in North America were larger-bodied notharctids and smaller-bodied omomyids. Through the Eocene, notharctids generally continued to increase in body size, whereas omomyids generally radiated within small- and increasingly mid-sized niches in the middle Eocene. This study examines the influence of changing body size and diet on the evolution of the lower fourth premolar in Eocene euprimates. The P4 displays considerable morphological variability in these taxa. Despite the fact that most studies of primate dental morphology have focused on the molars, P4 can also provide important paleoecological insights. We analyzed the P4 from 177 euprimate specimens, representing 35 species (11 notharctids and 24 omomyids), in three time bins of approximately equal duration: early Wasatchian, late Wasatchian, and Bridgerian. Two-dimensional surface landmarks were collected from lingual photographs, capturing important variation in cusp position and tooth shape. Disparity metrics were calculated and compared for the three time bins. In the early Eocene, notharctids have a more molarized P4 than omomyids. During the Bridgerian, expanding body size range of omomyids was accompanied by a significant increase in P4 disparity and convergent evolution of the semimolariform condition in the largest omomyines. P4 morphology relates to diet in early euprimates, although patterns vary between families. Am J Phys Anthropol 153:15-28, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

More than 25 new specimens of Teilhardina brandti, one of the oldest known euprimates, are reported from earliest Eocene strata of the southern Bighorn Basin, Wyoming. The new fossils include the first upper dentitions, a dentary showing the lower dental formula for the first time, and the first postcrania ascribed to T. brandti (tarsals and terminal phalanges). The elongated navicular and long talar neck suggest that T. brandti was an active arboreal quadruped, and the terminal phalanges constitute the oldest evidence for nails in Euprimates. Phylogenetic analysis incorporating the new data indicates that T. brandti is more derived than T. belgica but less so than T. americana. The hypothesis that Teilhardina originated in Asia ( T. asiatica) and dispersed westward to Europe ( T. belgica) and then to North America ( T. brandti and T. magnoliana) during the earliest Eocene Paleocene-Eocene Thermal Maximum is most consistent with available evidence, including the relative age of fossil samples and their stage of evolution. Am J Phys Anthropol, 2011. © 2011 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Extant mammals are classified into 4 to 8 locomotor guilds based on habitual behavior. Ungual phalanges are associated with load transmission during these behaviors, and hence may be useful in classifying species' locomotor guilds. This would be especially useful for evaluating fossil taxa. Previous research (MacLeod and Rose, 1993) has associated ungual shape with guild classification, but the biomechanics of ungual phalanges were not evaluated. This study examines osteometric linear distances and cross-sectional properties of manual ungual phalanges from 42 extant mammal species representing five locomotor guilds. Cross-sectional properties were examined with a pQCT scanner. Interestingly, fossorial and cursorial guilds, and arboreal and scansorial guilds, yield comparable results. Species classified as fossorial or cursorial have higher ratios of mediolateral to dorsopalmer bending strength compared to arboreal or scansorial species. Similar data for generalist terrestrial species overlap in range between the other locomotor guilds. Comparisons of flexor/extensor lever arm ratios fail to discriminate among taxa, with the exception of fossorial guild members. The results are compared with cross-sectional properties modeled from external measurements for application to fossil specimens. 15 fossil taxa are examined using these methods to assess possible locomotor guild memberships. [ABSTRACT FROM AUTHOR]