Peritidal cherts and silicified phosphorites of the Early Cambrian Kyrshabakta (Berkuta Member) and Chulaktau formations of South Kazakhstan contain diverse assemblages of cellularly permineralized microorganisms that like other microbiotas of similar age and setting are dominated by cyanobacteria, both filamentous (oscillatoriacean trichomes and empty sheaths) and coccoidal (chroococcaceans). Although these near-shore assemblages contain sphaeromorph acritarchs, they differ from Neoproterozoic and Early Cambrian microbiotas of more open-marine environments by lacking morphologically complex planktonic eukaryotes such as the acanthomorphic acritarchs that are abundant in the Chulaktau-overlying Shabakta Formation. In general composition, the Berkuta and Chulaktau assemblages are similar both to microfossil assemblages of the pre-trilobite Rovno and Lontova Regional Stages of the East European Platform and to Early Cambrian microbiotas known from chert-phosphorite deposits worldwide.

The studies reported here are based on use of optical microscopy combined with techniques recently introduced to paleobiology: confocal laser scanning microscopy, and Raman and fluorescence spectroscopy and imagery. Taken together, these provide information in situ, in three dimensions and at high spatial resolution, about the organismal morphology; cellular anatomy; chemical composition; and mode, fidelity, and environment of preservation of the permineralized microfossils. Data are presented suggesting that the substitution of samarium for calcium in fossil-preserving apatite may provide evidence of its oxic or anoxic paleoenvironment of formation.

We interpret the Berkuta and Chulaktau assemblages to be composed of 27 taxa assigned to 17 genera of microscopic prokaryotes and eukaryotes that include one new genus and species, Berkutaphycus elongatus.

Four trepostome bryozoan species are described from the Upper Triassic of New Caledonia. They include one new genus Metastenodiscus n. gen. The studied fauna shows strong paleobiogeographic relations to New Zealand and less so to Japan. Morphological similarities between Middle Paleozoic and Triassic trepostome bryozoans (e.g., abundant diaphragms) are explained by homeomorphy.

A remarkable fossil assemblage composed of five gastropod taxa is described from the Early Miocene of Santa Cruz (Patagonia, Argentina) in southernmost South America. The assemblage includes extinct and living genera South America, and on geographic distributions and represent background new information on spatial and across time distributions as well as identification of new taxa. A new taxon, Patagocharopa enigmatica n. gen. n. sp., is tentatively assigned to Charopidae. Gastrocopta patagonica n. sp. (Vertiginidae) represents the oldest record of Gastrocopta in Argentina and the southernmost record for the Americas. Punctum patagonicum n. sp. (Punctidae) represents the first record of Punctum for continental South America, and characterized by a protoconch with traces of axial costulae and a teleoconch with strong radial ribs. Zilchogyra miocenica n. sp. is the first Miocene record of the charopid genus Zilchogyra. Fragments of a possible Scolodonta (Scolodontidae) are recorded. Overall, the assemblage represents an important and useful paleoenvironmental tool. This fauna suggests that a more temperate and humid environment than today—with a more dense vegetation cover—was prevalent at this site during the Early Miocene.

Jacobsoniidae, comprising a small group of small-to-minute polyphagan beetles, is a family presently placed within Derodontiformia. No fossil jacobsoniid has been described to date. Here, we describe the first fossil jacobsoniid, Derolathrus groehni n. sp., based on two well-preserved individuals in middle Eocene Baltic amber. Micro–computed tomography (micro-CT) was used to reveal many diagnostic characters of the Recent genus Derolathrus Sharp. Derolathrus groehni is compared with modern Derolathrus species and is noteworthy for the well-developed eyes and elongate prothorax.

Forty-two conodont species belonging to 26 genera, which span the middle Darriwilian to the earliest Sandbian interval, are documented from the Wolonggang and Hatuke Creek sections in the Wuhai area of Inner Mongolia, North China. This conodont fauna is dominated by cosmopolitan and widespread species and accompanied by several endemic taxa. Four conodont zones, the Dzikodus tablepointensis, Eoplacognathus suecicus, Pygodus serra, and P. anserinus Zones, and three subzones, the Pygodus lunnensis, P. anitae, and Yangtzeplacognathus foliaceus Subzones, are recognized. Because of its slope habitat, the conodont fauna of Wuhai area differs from the coeval faunas on the North China Platform, which reflect a shallower and warmer water environment, but is similar to the contemporaneous faunas in Baltoscandia, South China, and Tarim. Moreover, the studied sections share several stratigraphically diagnostic taxa with the counterparts of the North China Platform and Western Newfoundland, which makes it an effective link for biostratigraphic correlations both regionally and internationally. The stratigraphically regular occurrences of Spinodus spinatus, a good index of a deep-water environment, represent a Spinodus biofacies that agrees with the Ordovician paleo-tectonic regimes of North China.

A specimen of a remarkable new catfish genus and species was collected in middle/late Miocene marine beds of the Puerto Madryn Formation at the base of the marine cliff of the sea lion colony area near Puerto Pirámide, southern coast of Península Valdés, northeastern Patagonia, Argentina. Siluriforms (catfishes) constitute a most important monophyletic ostariophysan group of mainly freshwater fishes that occurs in almost all continents but it is especially diverse in South America. Catfishes are presently distributed in tropical to temperate areas and a small number of species are marine or amphibiotic. The new catfish shows many primitive features for catfishes in the maxilla, autopalatine, hyal elements, and Weberian apparatus. The genus is clearly distinguished by four autapomorphies: sand clock–shaped autopalatine, posterior limb of autopalatine widening strongly, post-articular arm of autopalatine longer, and a metapterygoid longer than broad. One tree was obtained both under equal and implied weighting with the following topology: a basal polytomy in the Siluriformes formed by Diplomystidae, Bachmanniidae, Kooiichthys and the Siluroidei. The new species appears to have been a marine or amphibiotic taxon: it was collected in beds considered to represent the Maximum Flooding Horizon of the transgression that deposited the Puerto Madryn Formation. The coast at this moment was at approximately 90 km to the west. According to faunistic evidence, the sea was warm temperate.

Borings in fossil turtle shells collected from the lowermost beds of the early Eocene Cathedral Bluffs Tongue of the Wasatch Formation in the northwestern part of the Green River Basin near South Pass, Wyoming, are herein described. Individual turtle shells in the study area are characterized by as few as one or two and as many as >100 borings. The borings include both non-penetrative forms (those which do not pass fully though the shell) as well as penetrative forms (those which pass fully from the exterior to the interior surface of the shell). All non-penetrative forms occur on external surfaces of the carapace and plastron (i.e. those that would have been accessible while the host taxon was alive). Two new ichnogenera and four new ichnospecies are established to describe these borings. Karethraichnus (new ichnogenus) includes three ichnospecies: K. lakkos (new ichnospecies), K. kulindros (new ichnospecies), and K. fiale (new ichnospecies). Karethraichnus lakkos are shallow (non-penetrating), hemispherical pits with rounded, to flattened bases. Karethraichnus kulindros are deep, non-penetrative traces with a cylindrical profile, an axis approximately perpendicular to the substrate surface and with rounded to flattened, hemispherical termini. Karethraichnus fiale are penetrative traces with a cylindrical to bi-convex or flask-shaped profile, and an axis approximately perpendicular to the substrate surface. Thatchtelithichnus (new ichnogenus) Thatchtelithichnus holmani (new ichnospecies) consist of non-penetrative borings into a bone substrate. They consist of a ring-shaped trace, with a central pedestal or platform. The position of the borings on the shells, and evidence of syn-emplacement healing of the borings in several of the turtles, indicates that these borings were emplacement by ectoparasites/mesoparasites while the animals were living. Similar traces in modern emydid turtles are attributed to ticks, leeches, or spirorchid liver flukes.

Kinosternon Spix, 1824, was widespread in xeric to savanna associated paleowetlands across North America during the middle–late Miocene and steadily diversified following its first occurrences in the Hemingfordian. In the middle Miocene, Kinosternon rincon n. sp. occurred in the late Barstovian Cerro Conejo Formation of north central New Mexico, perhaps concurrently with Kinosternon pojoaque Bourque 2012a from the Tesuque Formation. Subsequent late Miocene kinosternine fossils indicate that at least three potentially contemporaneous species existed throughout the Clarendonian. These are Kinosternon pannekollops n. sp., from the Ogallala Formation of northern Texas; Kinosternon wakeeniense, n. sp., from the Ogallala Formation of northwestern Kansas and Ash Hollow Formation of south-central Nebraska; and Kinosternon notolophus n. sp., from the Alachua and Statenville formations of northern Florida. Kinosternon rincon is phylogenetically nested between the Kinosternon flavescens (Agassiz, 1857) group (=Platythyra Agassiz, 1857) and more derived Kinosternon including the Kinosternon subrubrum (Lacépède, 1788) group (=Thyrosternum Agassiz, 1857). Kinosternon pannekollops is recovered on the stem of the K. subrubrum group and is the oldest and largest member of that lineage. Kinosternon notolophus is readily differentiated from other Miocene Kinosternon in possessing a distinct dorsomedial keel on the nuchal and faint dorsolateral costal carination. The K. subrubrum group probably originated in the late Miocene savannas of the Great Plains and dispersed eastward via the Gulf Coastal Plain. An unnamed kinosternine taxon existed in the coastal plains of the eastern and southeastern United States during the Middle Miocene Climatic Optimum (with fossils from ~18 to 15 Ma), and disappeared from the region coincident with the end of that megathermal event.

The Zittel wing of Rhamphorhynchus muensteri is reinterpreted as preserving negative impressions of closely spaced broad flat actinofibrils that were replaced by calcite but were prepared away by the specimen’s finder. The Marsh specimen preserves positive impressions of the dorsal and ventral surfaces of the wing, which show that the skin was smooth with fine wrinkles and that actinofibrils were not on the wing surface. Based on comparisons of those specimens, the dactylopatagium consisted of dorsal and ventral skins of epidermis and dermis surrounding a common hypodermis core, and keratinous actinofibrils developed in place within the dorsal epidermis adjacent to a layer of linear collagen fibers in the dorsal dermis. The actinofibrils and linear collagen fibers together formed the main functional structure of the dactylopatagium. That structure made the dactylopatagium somewhat stiff and essentially inextensible so that it folded up along discrete fold lines that probably were genetically determined. A pneumatic retrophalangeal wedge behind the antebrachium through at least wing phalanx 3 streamlined the transition between the thick wing spar and thin patagium.

The Antarctic pelagornithid record is restricted to few isolated remains from the Eocene of Seymour Island in the Antarctic Peninsula. Here we report the oldest Antarctic pseudo-toothed bird. It is represented by an incomplete humerus lacking its proximal end, which comes from the lower Eocene levels of the La Meseta Formation (Seymour Island). This new specimen facilitates a review of all known pelagornithids from this continent. Antarctic pelagornithids were classified into two morphotypes that exhibit a mix of putative plesiomorphic and derived characters. Considering the worldwide pelagornithid record and according to estimated wingspans, four approximate size-types were identified. The oldest Antarctic specimens (two fragmentary humeri, middle Ypresian) were assigned to morphotype 1 and correspond to the large size-type. The younger materials (Bartonian/?Priabonian) here assigned to morphotype 2 (some cranial remains, fragmentary tarsometatarsus and humerus) correspond to the giant size-type and represent one of the largest known pseudo-toothed birds. Even though species level phylogenetic affinities of Pelagornithidae remain poorly resolved, three key evolutionary events can be recognized: (1) the disappearance of Dasornis in the Early Eocene and the appearance of more advanced forms with a trend to the specialization of large soaring capacity, (2) the origin of Pelagornis sensu lato species in the early Oligocene, and (3) the appearance and dominance of a highly specialized terminal group at Mio/Pliocene time span.

Remingtonocetidae are Eocene archaeocetes that represent a unique experiment in cetacean evolution. They possess long narrow skulls, long necks, fused sacra, and robust hind limbs. Previously described remingtonocetids are known from middle Eocene Lutetian strata in Pakistan and India. Here we describe a new remingtonocetid, Rayanistes afer, n. gen. n. sp., recovered from a middle to late Lutetian interval of the Midawara Formation in Egypt. The holotype preserves a sacrum with four vertebral centra; several lumbar and caudal vertebrae; an innominate with a complete ilium, ischium, and acetabulum; and a nearly complete femur. The ilium and ischium of Rayanistes are bladelike, rising sharply from the body of the innominate anterior and posterior to the acetabulum, and the acetabular notch is narrow. These features are diagnostic of Remingtonocetidae, but their development also shows that Rayanistes had a specialized mode of locomotion. The expanded ischium is larger than that of any other archaeocete, supporting musculature for powerful retraction of the hind limbs during swimming. Posteriorly angled neural spines on lumbar vertebrae and other features indicate increased passive flexibility of the lumbus. Rayanistes probably used its enhanced lumbar flexibility to increase the length of the power stroke during pelvic paddling. Recovery of a remingtonocetid in Egypt broadens the distribution of Remingtonocetidae and shows that protocetids were not the only semiaquatic archaeocetes capable of dispersal across the southern Tethys Sea.