Abelisaurid theropods are common members of Cretaceous Gondwanan faunas and are characterized by a bizarre, highly reduced forelimb. Unfortunately, forelimb elements are rarely preserved and thus the basic structure of the abelisaurid forelimb remains poorly understood. Until recently, the Upper Cretaceous Maevarano Formation of northwestern Madagascar has produced numerous exceptional specimens of the abelisaurid theropod Majungasaurus crenatissimus but comparatively little forelimb material. A recently discovered articulated skeleton of Majungasaurus preserves a virtually complete pectoral girdle and forelimb, which, along with additional isolated forelimb elements, affords important new insights into the structure of these elements. New specimens of the scapulocoracoid and humerus allow more detailed description of their morphology, and antebrachial and manual elements are described for the first time. The radius and ulna are approximately one-quarter the length of the humerus and both have expanded proximal and distal articular surfaces relative to their narrow diaphyses. The manus consists of four digits, each composed of a short metacarpal and one (digits I and IV) or two (digits II and III) phalanges. No ossified carpals are present. The proportions of the brachium and antebrachium are stout, more similar to the condition in Carnotaurus than in Aucasaurus. We reinterpret manual digit identities in Aucasaurus and Carnotaurus based on new information provided by the manus of Majungasaurus. Overall, the morphology of the forelimb in Majungasaurus reveals that abelisaurids share an extremely reduced, unique morphology that is dissimilar to the more typical theropod condition seen in other ceratosaurs.

A newly discovered osteichthyan ectopterygoid from the Upper Cretaceous (lower Cenomanian) Bahariya Formation of the Bahariya Oasis, Egypt, is nearly identical to the holotypic specimen of Polypterus? bartheli from the same area and geologic unit. The Bahariya ectopterygoids are referable to Polypteridae based on the presence of a robust, laterally directed process that articulates with the maxilla. Additionally, ganoid scales from the Bahariya Formation have an isopedine layer, a histological character of Polypteriformes; but differ from those of previously described members of this clade in having a discontinuous ganoin layer, rectilinear shape, and proportionally small articular processes. Both the ectopterygoids and the scales are unusually large, and are the only polypteriform remains so far identified from the Bahariya Formation. The ectopterygoids and (tentatively) the scales are herein assigned to a single species of gigantic polypterid, the morphology of which is sufficiently distinctive to warrant its placement in a new genus, Bawitius, gen. nov. Differences in scale anatomy and the enormous disparity in body size between Bawitius and Serenoichthys support the hypothesis (originally proposed on the basis of varied fin spine morphologies) that a diversity of polypterid fishes inhabited North Africa during the early Late Cretaceous.

Billfishes (Perciformes, Xiphioidei) are large marine teleosts characterized by an elongate rostrum formed primarily by greatly lengthened premaxillae. The billfish fossil record extends back to the late Paleocene, but is almost completely dominated by Northern Hemisphere finds despite the wide occurrence of several extant billfish species in southern seas. We report on an associated partial skeleton of a large billfish from upper Oligocene marine deposits on the South Island of New Zealand, described here as Aglyptorhynchus hakataramea, sp. nov. The material is assigned to Aglyptorhynchus—a genus previously known from the mid-Cenozoic of Europe and both the Atlantic and Pacific coasts of the U.S.A.—primarily on the basis of the ventrolaterally expanded flanges on its enlarged maxillae, diagnostic for the genus. It is recognized as a new species owing to its rostral proportions, and lower jaws that do not extend as far anteriorly as the tip of the rostrum as in other Aglyptorhynchus species. The new species is the most complete and informative fossil billfish described to date from the Southern Hemisphere.

A new species of Cacops, C. woehri, is described on the basis of a well-preserved skull from the Dolese Quarry locality in Oklahoma (Leonardian). Although its relatively small size and pattern of sculpturing indicate that the specimen probably represents a sub-adult individual, C. woehri differs from other members of the genus in the shallower shape of the skull, more dorsally located orbits, a distinct sculpturing pattern of radial ridges and grooves, and an ‘L’-shaped, narrow opening in the tympanic embayment. In addition, it differs from C. morrisi, the other anatomically well-known species of the genus, in the presence of a small posterior process of the postorbital contacting the supratemporal, in the presence of an ectoptery-goid fang, large occipital flanges of the postparietal and tabular, and in the shape of the basal plate of the parasphenoid. This new taxon highlights the morphological diversity of species within the enigmatic genus Cacops, with variation encompassing a distinct cranial morphology.

The nycteroleter parareptiles have lately become the focus of increased attention, owing to their recently recognized sister-group relationship to pareiasaurs and the discovery an impedance-matching ear in members of the group. The Kotel'nich locality in central Russia dates to the early part of the Late Permian and preserves a diverse tetrapod fauna that includes the pareiasaur Deltavjatia vjatkensis and the nycteroleter Emeroleter levis. The latter taxon was previously known only from isolated crania, but recent excavations have produced additional material, including well-preserved postcrania, allowing a complete redescription. The skull of Emeroleter is typified by dermal sculpturing consisting of evenly spaced small, round pits and supratemporals that extend posterolaterally into broad horns. The quadratojugal is long and the posterior portion of the element curves dorsally into a pointed projection, an autapomorphy of the taxon. Postcranially, Emeroleter is very gracile with a long, sigmoid femur, and slender limbs, carpal, and tarsal elements. A reassessment of the Russian nycteroleters results in the synonymy of Tokosaurus perforatus with Macroleter poezicus. Phylogenetic analysis of parareptilian relationships using both parsimony and Bayesian inference yields a monophyly of ‘nycteroleters’ in parsimony, whereas the group is found to be paraphyletic with Bayesian inference. The genus Bashkyroleter is consistently paraphyletic. A clade consisting of the nycteroleters and pareiasaurs, here termed Pareiasauromorpha, is supported by both methods.

The complete skeleton of a fossil mud turtle, Kinosternon pojoaque, n. sp., is described from the late Barstovian Rodent Pocket, San Ildefonso Locality of Santa Fe County, New Mexico. The new species represents the oldest member of the Kinosternon flavescens group and suggests that this clade first evolved in the southwestern United States, which, along with northern Mexico, is the center of diversity for these turtles today. The new taxon exhibits plastral characters that suggest phylogenetic affinities with Kinosternon angustipons, Kinosternon dunni, Kinosternon herrerai, Kinosternon hirtipes, and Kinosternon sonoriense and is interpreted here as an example of a morphological intermediate between the clade composed of these taxa and the flavescens group. The new fossil, along with other Miocene Kinosternon fossils from New Mexico, provides evidence that the flavescens clade likely diverged from other southwestern, Central, and South American Kinosternon by at least the late Barstovian, 14.3–13.3 million years ago.

A new mosasaur, Eremiasaurus heterodontus, gen. et sp. nov., from the Maastrichtian phosphates of Morocco is described based on the basis of two specimens: one consisting of a nearly complete skull, vertebral column, and isolated appendicular elements, and the other a nearly complete skull with associated vertebral column. This new mosasaur exhibits a high degree of heterodonty and a large number of pygal vertebrae, the latter feature expressed to a greater degree only in Plotosaurus from the Maastrichtian of California. Analysis of a data matrix of 135 characters and 32 terminal taxa resulted in three equally most parsimonious trees, and recovered E. heterodontus as the sister taxon to Plotosaurini. A second analysis incorporating five species of the globidensine mosasaur Prognathodon recovered 252 most parsimonious trees. This second analysis also recovered E. heterodontus as the closest relative to the Plotosaurini, a position supported by the presence of an internarial bar keel, exclusion of the prefrontals from the narial borders, narial embayments in the frontal, and the presence of a quadrate ala groove. A change in the positions of several key character-state changes in the second analysis not only supports the exclusion of E. heterodontus from the globidensine mosasaurs, but also calls into question the monophyly of the Globidensini and the suite of quadrate and dental characters used to diagnose this group.

A lower jaw and associated postcranial remains from the Late Cretaceous—early Paleocene Hornerstown Formation of New Jersey form the basis of a new crocodyliform species, Borealosuchus threeensis. Although one of the oldest known species of Borealosuchus, phylogenetic analysis supports a closer relationship to Borealosuchus from the early Eocene than with other Late Cretaceous or early Paleocene forms. This is based on the shared presence of a short mandibular symphysis excluding the splenial, a small external mandibular fenestra, and ventral osteoderms composed of two sutured ossifications. It is also similar to Borealosuchus material from the Paleocene of western Texas, though conspecificity cannot be demonstrated at present. A close relationship with the basal alligatoroids Leidyosuchus or Diplocynodontinae is not supported. The distribution of lower jaws with very small slit-like external mandibular fenestrae, or no fenestrae at all, among basal crocodylian lineages (including Borealosuchus) and close crocodylian relatives suggests the fenestrae may have been ancestrally absent in Crocodylia and regained two or more times. Current phylogenetic hypotheses are consistent with dispersal of more-derived species of Borealosuchus to the Western Interior during the Paleocene, and they indicate the presence of several unsampled lineages crossing the Cretaceous-Paleogene boundary.

Two new fossil crania of Old World vultures (Accipitridae, Aegypiinae), from the middle Pleistocene Jinniushan site of Liaoning Province, northeastern China, were studied. A new species of Aegypius, A. jinniushanensis, is erected and characterized by possessing a less developed processus zygomaticus and processus suprameaticus, as well as a relatively larger condylus occipitalis, compared with A. monachus. Another specimen, assigned to Torgos, is the first record of this genus from outside Africa. The presence of two large vultures, apparently in the same feeding group, in the Jinniushan faunal assemblage suggests that there were more opportunities for interspecific competition among scavengers in the middle Pleistocene of northeastern China than at present. By analogy with phylogenetically related modern vultures, we suggest that niche differentiation between the two extinct species may have reduced the degree of competition between them. The disappearance of the genus Torgos from northeast China might be the result of the Pleistocene extinction of a suite of large mammalian herbivores, and the loss of grassland and savannah from this region.

Here we describe the most plesiomorphic koala yet known. Priscakoala lucyturnbullae, gen. et sp. nov., is the fourth and largest koala species described from Miocene deposits in the Riversleigh World Heritage area, northern Australia. It is known from a maxilla with M1–3 and isolated M2, M3 or M4 and m1. Relationships within the diprotodontian suborder Vombatiformes are clarified using cranial and dental characters based on a data set compiled from new and more complete cranial materials for each of the respective vombatiform families. Monophyly of Phascolarctidae is supported by the development of a protostylid and metastylid on m1. Priscakoala lucyturnbullae is the most plesiomorphic phascolarctid. Inclusion in the analysis of the enigmatic Pliocene genus Koobor, currently classified as Vombatiformes incertae sedis, indicates phascolarctomorphian affinities for the genus.

A partial skeleton of an adult mylagaulid rodent was collected in 1959 near Durham, Roger Mills County, Oklahoma, but the specimen was not prepared until 2010–2011. The specimen is a part of the Durham local fauna, of late Clarendonian (late Miocene) age. Several other isolated premolars previously published from the same locality give some indication of dental and morphological variation in the population sample. The new skeleton includes a complete cranium with two large horns on the nasals, associated dentaries, and some of the postcranial skeleton. The only mylagaulids previously reported to have nasal horns are Ceratogaulus rhinocerus, C. hatcheri, C. anecdotus, and Ceratogaulus (or Mylagaulus) minor (Hibbard and Phillis). There is discord about the classification of horned mylagaulines; problematically, an abundance of isolated teeth and paucity of skulls are found as fossils and sometimes were named as new taxa. Some authors place all horned mylagaulines in Ceratogaulus, whereas others place the taxon minor in Mylagaulus, indicating that at least one species (M. minor) of that genus has horns. The Oklahoma specimen has P4s with occlusal features considered diagnostic of Mylagaulus and is referred to that genus. Dentally the new specimen is most similar to the type specimen of Epigaulus minor Hibbard and Phillis, which is now variously placed in the genus Mylagaulus or Ceratogaulus. The nasal horns on the Durham cranium are distinct from the horns of all known horned mylagaulids in bearing large longitudinal furrows posteriorly. Accordingly, the Durham specimens are placed in a new species, Mylagaulus cornusaulax.

The Mylagaulidae are a family of extinct fossorial rodents that are common in the North American Miocene. Alphagaulus pristinus, from the Barstovian of Montana, was previously known only from partial dentaries and isolated teeth, with no well-described skull or postcranial material. Alphagaulus is important to understanding the evolution of burrowing in mylagaulids, because it is within this genus that the most dramatic evolution of fossorial morphology within mylagaulids occurs. The other three species of the genus are all known from partial skulls, rare isolated postcrania for Alphagaulus vetus, and, in the case of Alphagaulus tedfordi, a nearly complete skeleton. We describe new material housed at the University of Washington Burke Museum, including three well-preserved skulls and partial skeletons showing different ontogenetic stages from juveniles to an adult. The description of this new material gives insights into the ontogeny of these burrowing mammals. In particular, it is apparent that the developmental trajectory mimics evolution in the increase of fossorial modifications of the skeleton with time. The description of these specimens also allows reanalysis of the phylogenetic relationships within the Mylagaulidae, confirming that the genus Alphagaulus is paraphyletic. Though the phylogenetic positions of species within the genus are different, our results are more stable than those of previous analyses, allowing greater confidence in the reconstructed relationships among mylagaulid species and genera.

The Jebel Qatrani Formation in the Fayum Depression, Egypt, has yielded a diverse hyracoid fauna that includes both small- and large-bodied forms. Thyrohyrax domorictus is one of the most common hyracoids found in the upper sequence of the Formation, from sites dating to between 29 and 31 Ma. The dental morphology of T. domorictus is more similar to that of living hyraxes than other Paleogene species, but additional morphological evidence is needed to test the hypothesis of procaviid affinities. Two fairly complete crania of T. domorictus are now known and provide a number of additional craniofacial characters for phylogenetic analysis. The specimens are comparable in size to other small-bodied Fayum hyracoids and extant procaviids. T. domorictus has a relatively long rostrum that is perforated by a nasomaxillary fossa, which is also present in Miocene Afrohyrax and Prohyrax and older Thyrohyrax pygmaeus. The anterior border of the orbit is positioned above the molars, and the orbital aperture is closed posteriorly by a complete postorbital bar. Compared to other Fayum hyracoids, T. domorictus exhibits relatively derived, and more procaviid-like, cranial morphology. The cranium of T. domorictus is most similar to that of the extant genus Dendrohyrax, and they share similar morphology of the orbit and cranial roof. Phylogenetic analysis including morphological and molecular data from a large sample of living and extinct afrotherians places Thyrohyrax domorictus as the closest known Paleogene relative of Procaviidae and Pliohyracidae, supporting the hypothesis of procaviid affinities that was originally proposed solely on the basis of dental morphology.

We revise here the entire collection of Bovidae from the Pliocene Hadar Formation collected at Hadar and Ledi-Geraru, Lower Awash, Ethiopia. Some additions are provided to previously published descriptions, and other forms are described. The complete list includes 28 species, but is dominated by a new species of impala, Aepyceros datoadeni, a kob that we assign to Kobus oricornus, although it belongs to a type distinct from the Omo one, a lineage of alcelaphins that is poorly known elsewhere, Damalborea, and the bovin Ugandax. We also describe a new gazelle, Gazella harmonae, with very peculiar features, including long spiraled horn cores. Changes in the bovid fauna can be detected both within individual lineages, and in the composition of the assemblage. Impala and bovins far outnumber the reduncins in the lower part of the sequence (Basal and Sidi Hakoma members, from ca. 3.8 to 3.2 Ma), but relative abundances become more equal higher up. Biometric changes do occur in the Ugandax and Aepyceros lineages, but are not significant in other lineages. The major evolutionary events occur in the KH1 or KH1/KH2 transition, ca 3.1–3.0 Ma, with appearance of a third tragelaphin species, of a very small alcelaphin and of a large Aepyceros, and the likely disappearance of K. oricornus.

A new genus and species of extinct inioid odontocete (Meherrinia isoni) is based on nine partial crania that probably originated from the late Miocene marine Eastover Formation in North Carolina, U.S.A. They were collected from the riverbed of the Meherrin River, a tributary of the Chowan River. Ossification of the mesethmoid and the tight inter-digitation of many sutures indicate that these specimens represent mature individuals. Key characteristics of the new inioid include maxillae that ‘squeeze’ the nasals into a slight hourglass shape and supraoccipital that is deeply wedged between the frontals and maxillae on the vertex. As compared to the extant iniid Inia geoffrensis (Amazon River dolphin) and the extant pontoporiid Pontoporia blainvillei (La Plata dolphin), Meherrinia is more plesiomorphic in having less elevated premaxillary eminences and supraorbital processes. In other respects Meherrinia is intermediate in morphology between the two extant genera of inioids. For example, the essentially symmetrical vertex is intermediate in height between the low and high vertices in Pontoporia blainvillei and Inia geoffrensis, respectively. A cladistic analysis of morphological and molecular data supports a sister-group relationship between Meherrinia and Inia; thus our new taxon is tentatively assigned to the Iniidae. If correct, this is the first iniid represented by diagnostic remains from marine deposits and just the second from North America.