A well-preserved omission surface (sedimentary discontinuity) in an outcrop near Alcoi in southeastern Spain displays trace fossils and body fossils that reflect a dynamic benthic community during the Miocene (Langhian–Tortonian). This outcrop, besides being the type locality of Spongeliomorpha iberica Saporta, 1887, exhibits other abundant trace fossils, such as Glossifungites saxicava Łomnicki, 1886 and Gastrochaenolites ornatus Kelly and Bromley, 1984. These trace fossils are restricted to a single stratigraphic horizon and constitute a typical firmground ichnoassemblage of the Glossifungites ichnofacies. The interiors of some of the Glossifungites and Spongeliomorpha burrows were occupied by encrusting balanomorph barnacles (Actinobalanus dolosus Darwin, 1854). This paper is the first report of cryptic barnacles colonizing the interior of open burrows that constitute a typical firmground ichnocoenose in the fossil record. Detailed ichnologic study demonstrates that the ichnospecies Glossifungites saxicava stands as a valid ichnotaxon and is not a synonym of the ichnogenus Rhizocorallium, as has been suggested by some previous workers.

We report three isolated humeri of small-sized parareptiles, which represent two different taxa, from the lower Keuper (Erfurt Formation) of Germany. They constitute the first definitive evidence of parareptiles in the lower Keuper. The specimens represent the first records of an owenettid procolophonian (aff. Barasaurus) from Europe and of a putative gracile-built procolophonid. This indicates the coexistence in the Middle Triassic of Germany of two procolophonian lineages that first appeared in the fossil record in the late Permian and survived the Permian–Triassic extinction. Although based on isolated limb bones, they highlight the taxonomic diversity of the still poorly known tetrapod assemblage of the lower Keuper in southwestern Germany.

Two new Raninoida crabs from the Cretaceous of Texas are described, Planocorystes robreidi new genus new species, and Texicancer new genus to accommodate Necrocarcinus renfroae. All the previously described raninoid-like decapods from the Pawpaw Formation have been reassigned according to Karasawa et al. (2014). Cretaceous raninoid-like crabs are the dominant taxa amongst the fossil decapods found in the Fort Worth, Texas, area, with hundreds of specimens collected. All of these fossils have been collected from limonitic nodules, and most of them present a good degree of preservation, with articulated pereiopods, pleons, venter and in rare occasions even the gills. The decapod fauna of the Pawpaw Formation represents a diverse population, with a large number of taxa in high abundance. One specimen of P. robreidi appears to exhibit a lethal bite mark.

Sauropod dinosaurs are rare in the Cretaceous North American fossil record in general and are absent from that record for most of the Late Cretaceous. Sonorasaurus thompsoni from the Turney Ranch Formation of the Bisbee Group of Arizona, USA, potentially represents one of the youngest sauropods before their ca. 30-million-year-long hiatus from the record. The anatomy of Sonorasaurus has only been briefly described, its taxonomic validity has been questioned, several hypotheses have been proposed regarding its phylogenetic relationships, and its life history, geologic age, and reported paleoenvironment are ambiguous.

Herein we assess the systematics, paleoenvironment, life history, and geologic age of Sonorasaurus based on firsthand observation, bone histology, and fieldwork in the holotypic quarry and environs. The validity of S. thompsoni is substantiated by autapomorphies. Cladistic analysis firmly places it within the Brachiosauridae, in contrast to results of some recent analyses. Bone histology suggests that the only known exemplar of Sonorasaurus grew slowly and sporadically compared to other sauropods and was approaching its adult size. In contrast with previous assessments of a coastal/estuarine paleoenvironment for the Turney Ranch Formation, our sedimentological and plant macrofossil data indicate that Sonorasaurus lived in a semiarid, low relief evergreen woodland that received highly variable (perhaps seasonal) precipitation. We obtained detrital zircons from the holotypic quarry for U-Pb dating, which only yielded Barremian-aged and older grains, whereas other radiometric and biostratigraphic data suggest that the sediments at the quarry were deposited near the Albian-Cenomanian boundary.

Sonorasaurus is taxonomically valid, represents one of the geologically youngest brachiosaurid sauropods, and inhabited a harsh inland evergreen-dominated woodland environment that limited its growth. A review of other Bisbee Group dinosaurs suggests that its fauna, although poorly sampled, exhibits broad similarity to those from coeval North American horizons, reinforcing the apparent faunal homogeneity at the time.

Fieldwork conducted in the Wasatch Formation in and around Fossil Butte has yielded a diverse assemblage of early Eocene vertebrates. Fossil vertebrates are distributed through three discrete stratigraphic intervals within the uppermost 180 m of the main body of the Wasatch Formation underlying the Green River Formation. These assemblages were derived primarily from fluvial overbank mudstone units overprinted with variably well-developed paleosols. The lowest (20 m) and highest (60 m) sections are characterized by less mature and more hydromorphic paleosols, whereas the middle section (100 m) is typified by more mature paleosols and more abundant channel sandstones.

The combined assemblages contain at least 46 species of mammals. Faunal characteristics include high abundances of equid perissodactyls and a relatively high abundance and diversity of notharctines primates, an apparent absence of omomyid primates, relatively high rodent diversity, and relatively diverse and abundant artiodactyls. One new genus (Eoictops new genus) and three new species (Eoictops novaceki new species, Palaeosinopa lacus new species, and ?Notoparamys blochi new species) are included in the Fossil Butte assemblage. Also recorded are late occurrences of two hyopsodontid condylarths and an early occurrence of a rare phenacodontid condylarth. The relatively high abundances of equids and notharctines suggest that vertebrate samples were derived from relatively open paleohabitats that included forested areas along water courses.

All three assemblages contain characteristic Lysitean (Wasatchian biochron Wa-6) elements, but the occurrence of the palaeotheriid perissodactyl Lambdotherium in the uppermost horizon indicates a Lostcabinian (Wa-7) age for at least the top of the Wasatch Formation. The overlying predominantly fish-bearing Fossil Butte Member of the Green River Formation also contains Lambdotherium and is therefore Wa-7 in age as well.

Fossil catostomids were very rare prior to the Eocene. After the Eocene, they suddenly decreased in diversity in Asia while becoming common fishes in the North American fauna. Knowledge of the taxonomy, diversity, and distribution of Eocene catostomids is critical to understanding the evolution of this fish group. We herein describe a new catostomid species of the genus †Amyzon Cope, 1872 from the Eocene Kishenehn Formation in Montana, USA. The new species, †Amyzon kishenehnicum, differs from known species of †Amyzon in having hypurals 2 and 3 consistently fused to the compound centrum proximally, and differs from other Eocene catostomids in that the pelvic bone is intermediately forked. All our phylogenetic analyses suggest that the new species is the sister group of †A. aggregatum Wilson, 1977 and that †Amyzon is the most basal clade of the Catostomidae. We reassessed the osteological characters of the North American species of †Amyzon from a large number of well-preserved specimens of the new species, as well as †A. gosiutense Grande et al., 1982 and †A. aggregatum. Osteological characters newly discovered indicate that †A. gosiutense is not a junior synonym of †A. aggregatum, but should be retained as a distinct species.

Fossil fish are poorly represented in middle Lower Devonian deposits of the western United States. Here we describe vertebrate microremains from mid-Pragian levels in the Kobeh Member, McColley Canyon Formation, central Nevada. The species diversity of the assemblages is low and dominated by the acanthodian Nostolepis costata Goujet, 1976. This species is found in older (late Lochkovian–early Pragian) deposits in France and Spain and mid-Pragian or slightly younger deposits in Saudi Arabia. This distribution suggests dispersal to the west from the Armorica terrane around the south of Laurussia to the Nevada region, and southeastward to Arabia, on the northern margin of Gondwana.

A new fossil species of Dermestidae (Insecta: Coleoptera), preserved in Late Cretaceous (Turonian) amber from New Jersey, is described as Attagenus (Aethriostoma) turonianensis n. sp. The specimen is fossilized in translucent amber, but 3D imaging using propagation phase-contrast X-ray synchrotron microtomography allowed detailed classification and description. This species is the oldest representative of the subfamily Attageninae and the third fossil species described in the family from the entire Mesozoic. Dermestidae comprise beetle species that typically feed on carcasses, although some Recent species of Attagenus Latreille, 1802 are known to feed on plant debris, which is highly abundant in amber deposit sediments. This new species is evidence for diversification in the family during the Early Cretaceous as well as long morphological conservation of diagnostic features of the genus Attagenus from the Late Cretaceous. Analyzing the taxa from Mesozoic ambers that show stasis, the small size of the specimens together with a specific ecology could explain the stability of these lineages.

The Careless Creek Quarry (CCQ) is a multitaxic bonebed in the Campanian Judith River Formation of south-central Montana (USA) that produced a diverse assemblage of vertebrates, including several dinosaurian clades. We describe the morphology of the CCQ hadrosaurid material and reevaluate its taxonomic affinities. Our osteological comparative observations, coupled with maximum parsimony phylogenetic analyses, indicate that the majority of the hadrosaurid material is referable to kritosaurin saurolophines. Only an ischium is unambiguously referable to Lambeosaurinae. Most of the kritosaurin specimens likely represent a taxon that forms a polytomy with species of Gryposaurus and Rhinorex condrupus Gates and Sheetz, 2015. This form may represent individuals of either G. latidens Horner, 1992 or G. notabilis Lambe, 1914, or a new species cogeneric or not with Gryposaurus. The juvenile material exemplifies several patterns of mandibular and appendicular osteological variation previously observed in other hadrosaurids. However, it also shows some departures from the common trends, supporting the fact that not all skeletal growth changes can be generalized to all hadrosaurids.

Moore and Strimple described the Morrowan (Lower Pennsylvanian, Bashkirian) crinoid Zenocrinus zeus, and noted significant differences in the number and arrangement of plates in the posterior interray between the holotype and the paratype, the only known specimens. A reexamination of the type specimens allowed for a reconciliation of these discrepancies. The new interpretation of Z. zeus necessitates a revision of the diagnosis, and a new plate diagram is proposed. Additional morphological features of the species are described, including the presence of a generating columnal between the column proxistele and mesistele, and a ratcheting profile for the exterior surfaces of calyx ray plates.

Based on a single right cheliped from the Cape de Naze Formation (middle–upper Maastrichtian), Senegal, a new genus and species of hermit crab with capsulated setae is described. Paracapsulapagurus poponguinensis n. gen. n. sp. is characterized by platy, scale-like, non-spinose tubercles with setae arranged in curved rows. This is only the third record of a fossil hermit crab with capsulated setae. These are documented in detail using SEM-imaging. For the first time, capsulated setae are also figured for the Early Jurassic hermit crab Schobertella.

We report the first Tertiary bird fossil from Central America, an ungual phalanx from a large, unknown genus and species of Accipitridae from the early Miocene Centenario Fauna, Panama. This specimen provides another example of a Neogene bird from North and Central America with its possible closest living relatives occurring today in Africa. In contrast, there is no evidence of African affinities among the reptile or mammal fossils from the Centenario Fauna.

New cranial and postcranial material of the baenid turtle Neurankylus from the Paleocene Nacimiento Formation (Torrejonian NALMA) of northwestern New Mexico represents a new species, Neurankylus torrejonensis. The material consists of a fragmented but mostly complete skull, a partial carapace and plastron, portions of both humeri, a partial pelvis, a complete right femur, and a distal phalanx. The small, undivided cervical scale, wide vertebrals, complete ring of marginals, and large size (carapace length 520 mm) diagnose the new taxon as belonging to Neurankylus. The narrow fifth vertebral scale and scalloped posterior shell margin reveal affinities with Neurankylus baueri Gilmore, 1916, which is known from Campanian sediments in New Mexico and Utah. The holotype of Neurankylus torrejonensis is the youngest known specimen of the Neurankylus lineage, which is known to reach at least back to the Late Cretaceous (Santonian). A nearly complete species-level analysis of baenids confirms the basal placement of Neurankylus outside of Baenodda and the split of Baenodda into two primary subclades, herein named Palatobaeninae and Eubaeninae.

Although Ptychodus teeth are well known in Late Cretaceous marine deposits in North America and Europe and a few specimens with jaw elements have been discovered, the taxonomic position of the shark genus Ptychodus is enigmatic due to the lack of preservation of diagnostic material other than teeth. These sharks possessed a pavement dentition suited to a diet of hard-shelled macroinvertebrates (durophagy), leading several studies to variously describe Ptychodus as a batoid, a hybodont shark, or a selachimorph. Members of the Selachimorpha share one dental synapomorphy, a triple-layered enameloid (TLE) consisting of an outer shiny-layered enameloid (SLE) of randomly oriented hydroxyapatite crystallites, a middle layer of parallel-bundled enameloid (PBE), and an inner layer of tangled-bundled enameloid (TBE). Batoids and hybodonts both have teeth with single crystallite enameloid (SCE). We examined teeth from Ptychodus collected from the Lincoln Limestone of the Greenhorn Formation of Barton County, Kansas, and compared their enameloid ultrastructure with that of a Carboniferous hybodontiform and the Cretaceous lamniform shark Squalicorax curvatus Williston, 1900. Scanning electron microscopic examination of Ptychodus shows that crystallite bundling in the form of a TLE is evident in these teeth. The PBE is most apparent at transverse enameloid ridges of Ptychodus teeth. Columns of dentine penetrate into the tooth enameloid, and the crystallites near the dentine are randomly oriented. These observations bolster the argument that Ptychodus is a genus of highly specialized selachimorph shark, rather than a hybodont or batoid.

Despite a rich and varied record, Mesozoic stalked crinoids are relatively rare in the Western Interior Seaway of North America compared to those found in Northern Europe. A unique example of Mesozoic stalked crinoid is described from cold methane seeps (hydrocarbon seep mounds also called “tepee buttes”) from the Upper Cretaceous (upper Campanian) of the Northern Great Plains of the United States; the first crinoids to be described from such an environment. The Late Cretaceous Western Interior Seaway has never before yielded any identifiable stalked crinoid remains. Nevertheless, there have been significant studies on both free living and stalked crinoids from other locations in the Upper Cretaceous of North America that provide a good basis for comparison. Lakotacrinus brezinai n. gen. n. sp. is characterized by a tapering homeomorphic column with through-going tubuli, lacking any attachment disc. The arms are unbranched and pinnulate, with muscular and syzygial articulations. The unique morphology of the column justifies the establishment of Lakotacrinidae new family. A new suborder Lakotacrinina n. subord., is also proposed as there exists no corresponding taxon within the Articulata that can accommodate all the characteristics of this new genus. This new crinoid shares many features with other members of the articulates, including bathycrinids, bourgueticrinids and guillecrinids within the Order Comatulida, as currently defined in the revised Treatise of Invertebrate Paleontology. Reconstructing the entire crinoid using hundreds of semi-articulated and disarticulated (well preserved) fossils, reveals a unique paleoecology and functional morphology specifically adapted to living within this hydrocarbon seep environment.

Alligators and caimans share a close relationship, supported by both molecular and morphological characters. The divergence between alligators and caimans has been difficult to discern in the fossil record. Two basal taxa have recently been described from the Miocene of Panama and Venezuela but have not yet been presented in a joint phylogeny. Continued preparation of the type material of the Venezuelan Globidentosuchus brachyrostris Scheyer et al., 2013 has revealed new characters for scoring in a cladistic framework. In addition, the first lower jaw of the Panamanian Centenariosuchus gilmorei Hastings et al., 2013 is described herein, and additional characters were scored. In total, we conducted five cladistic analyses to better understand the character evolution involved in the establishment of Caimaninae. In each case, Globidentosuchus appears as the basal-most of the caimanine lineage, followed by Culebrasuchus mesoamericanus Hastings et al., 2013 from Panama. Stepwise character additions of synapomorphies define progressively more derived caimanines, but stratigraphic context creates ghost lineages extending from the Miocene to Paleocene. The persistence of two basal taxa into the Miocene of northern South America and Central America supports the concept of a relict basal population in this region. This further supports biogeographic hypotheses of dispersals in both directions between North and South America prior to full land connection.

Rhuddanian crinoid faunas are poorly known globally, making this new fauna from the Hilliste Formation of western Estonian especially significant. The Hilliste fauna is the oldest Silurian fauna known from the Baltica paleocontinent, thus this is the first example of the crinoid recovery fauna after the Late Ordovician mass extinction. Hiiumaacrinus vinni n. gen. n. sp., Protaxocrinus estoniensis n. sp., Eomyelodactylus sp., calceocrinids, and five holdfast types are reported here. Although the fauna has relatively few taxa, it is among the most diverse Rhuddanian faunas known. Similar to other Rhuddanian crinoid faunas elsewhere, the Hilliste crinoid fauna contains crinoids belonging the Dimerocrinitidae, Taxocrinidae, Calceocrinidae, and Myelodactylidae; most elements of the new fauna are quite small, perhaps indicative of the Lilliput Effect.

Heavily tuberculated glyptosaur osteoderms were collected in an active limestone quarry in northern Berkeley County, South Carolina. The osteoderms are part of a highly diverse late Paleocene vertebrate assemblage that consists of marine, terrestrial, fluvial, and/or brackish water taxa, including chondrichthyan and osteichthyan fish, turtles (chelonioid, trionychid, pelomedusid, emydid), crocodilians, palaeopheid snakes, and a mammal. Calcareous nannofossils indicate that the fossiliferous deposit accumulated within subzone NP9a of the Thanetian Stage (late Paleocene, upper part of Clarkforkian North American Land Mammal Age [NALMA]) and is therefore temporally equivalent to the Chicora Member of the Williamsburg Formation. The composition of the paleofauna indicates that the fossiliferous deposit accumulated in a marginal marine setting that was influenced by fluvial processes (estuarine or deltaic).

The discovery of South Carolina osteoderms is significant because they expand the late Paleocene geographic range of glyptosaurines eastward from the US midcontinent to the Atlantic Coastal Plain and provide one of the few North American records of these lizards inhabiting coastal habitats. This discovery also brings to light a possibility that post-Paleocene expansion of this group into Europe occurred via northeastward migration along the Atlantic coast of North America.

The Field Museum of Natural History collection contains several isolated hadrosaurid specimens collected by Charles H. Sternberg from the lower Kirtland Formation of the San Juan Basin, New Mexico, that have been previously overlooked. Cranial elements described herein consist of a dentary and three jugals while appendicular material is limited to two humeri and two pubes. Many of the specimens preserve taxonomically informative characters that show strong affinities with Kritosaurini but are distinct from Kritosaurus navajovius (Brown, 1910) suggesting that the saurolophine-dominated San Juan Basin diversity is greater than currently recognized. Future examination of currently unprepared material will add to our developing understanding of the ambiguous hadrosaurid diversity of the San Juan Basin.