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The Bajocian–Oxfordian Dalichai Formation of the Binalud Mountains (northeastern Iran) consists of marls, marly limestones and limestones that were sampled and studied in detail for their palynomorph and ammonite contents. Palynological studies enabled differentiation of three marine biozones (Cribroperidinium crispum, Dichadogonyaulax sellwoodii, and Ctenidodinium continuum) within the lower interval of the formation. The palynofacies analysis shows a gradual sea-level rise during the depositional period of the rock unit, while terrestrial palynomorphs (spores and pollen grains) revealed a predominantly tropical climate for the time interval. Furthermore, a large number of ammonites were recovered from the formation, based on which 12 families, 22 genera, 30 species and 12 biozones (Zigzag, Aurigerus, Retrocostatum, Discus, Bullatus, Gracilis, Anceps, Coronatum, Athleta, Transversarium, Bifurcatus, and Bimammatum) were differentiated. When comparing the dinoflagellate cyst zones with the ammonite zones, the Dichadogonyaulax sellwoodii dinoflagellate cyst zone was correlated with the ammonite zones of Zigzag, Aurigerus, Retrocostatum, Discus, Bullatus, and Gracilis and the Ctenidodinium continuum dinocyst zone was correlated with the Gracilis and Anceps ammonite zones. The dinocyst and ammonite assemblages of the Binalud Mountains are similar to assemblages described from northern and northeastern Iran (Alborz and Koppeh-Dagh basins) as well as Northwest Europe. This suggests marine connections between these sedimentary basins during the Bajocian–Oxfordian. Consequently, the integrated dinocyst and ammonite zonation established here can be utilized also in other parts of the northern Tethyan Realm. The diachroneity of the upper boundary of the Dichadogonyaulax sellwoodii Zone between the Binalud Mountains and Northwest Europe is however revealed by comparison with the ammonite zones.

In a strict sense, palaeoscolecids are a group of cycloneuralian worms (ecdysozoans) characterized by the tessellation of trunk sclerites, which are differentiated into plates, platelets, and microplates. The Wangcun section in western Hunan, South China, which represents the Furongian Series (upper Cambrian), has yielded a rich and diverse collection of palaeoscolecids. However, there is uncertainty about how the morphology and arrangement of their sclerites change during ontogeny and the potential taxonomic implications of these changes. Here, we report new phosphatized trunk fragments from the Wangcun section, which are assigned to Dispinoscolex decorus, Hunanoscolex campus (= Ornatoscolex hunanensis), and Schistoscolex hunanensis. Trunk fragments of the same species with different diameter indicate the presence of several ontogenetic stages, and careful assessment revealed two types of sclerite growth patterns. One is represented by D. decorus and possibly also by S. hunanensis, in which the worm growth is accompanied mainly by the enlargement of the plates, with almost no change in the median annular zones and annulation boundaries. The other type is represented by H. campus, in which the worm growth is accompanied mainly by the widening of the median annular zones and annulation boundaries inserted with continuously more platelets and microplates. Because the specimens originally assigned to H. campus seem to represent late ontogenetic stages of O. hunanensis, we propose that H. campus is a senior synonym of the latter. This study underscores the importance of ontogenetic variation of sclerites for the taxonomy of palaeoscolecids, and highlights the significance of Orsten-type fossils in the study of metazoan ontogeny.

A comprehensive record of unique and endemic species of “Giraffa” priscilla has been documented and reported from the Chinji Formation of Lower Siwaliks, Pakistan. The material comprises incisors, canines, premolars, molars, mandibular and maxillary fragments which have been recovered from the Middle Miocene localities of Dhok Bun Ameer Khatoon, Rakh Wasnal, Bhelomar, and Lawa, Punjab, Pakistan. “Giraffa” priscilla is a primitive species of giraffids, having a broad crown, strong styles, and median ribs.

The Naqing section in Luodian (Guizhou, South China) contains a deep-water carbonate-dominated succession of the Late Devonian through the Permian. In this study, 72 conodonts species/subspecies of 11 genera were obtained from the lower part of this section including. Seven middle to late Famennian and four early to late Tournaisian conodont biozones were recognized as, in ascending order, Palmatolepis marginifera marginifera Zone, Palmatolepis marginifera utahensis Zone, Polygnathus granulosus Zone, Palmatolepis rugosa trachytera Zone, Polygnathus styriacus Zone, Palmatolepis gracilis manca Zone, Palmatolepis rugosa rugosa Zone, Siphonodella isosticha Zone, Gnathodus punctatus Zone, Gnathodus typicus-Gnathodus cuneiformis Zone, and Gnathodus typicus-Protognathodus cordiformis Zone. Several key conodont biozones across the Devonian–Carboniferous Boundary (DCB) interval found elsewhere are not discovered in the Naqing section, likely due to a conodont-barren interval in the siliciclastic facies. The middle Famennian–late Tournaisian conodont biozones illustrated in this study provide a robust chronostratigraphic framework for further research on biotic and paleo-environmental events during the Late Devonian through Early Mississippian critical greenhouse-icehouse climate transition.

Phu Kao-Phu Phan Kham Mountain ranges, situated on the border of Nong Bua Lamphu, Udon Thani, and Khon Kaen provinces, northeastern Thailand, bear several localities that yield dinosaurs and other vertebrate faunas in the Lower Cretaceous. However, this area has received relatively little attention from the scientific community and the public. Here we review and report new dinosaur materials recovered from this region, some found decades ago, others discovered recently. We identify and discuss their taxonomy and paleobiodiversity. In the Barremian Sao Khua Formation, theropod dinosaurs were represented by spinosaurids, an early branching megaraptoran, a large indeterminate theropod, and small indeterminate theropods. Sauropods were represented by an indeterminate sauropod, a neosauropod, and titanosauriforms, including probable brachiosaurid and non-titanosaur somphospondylans. Other vertebrate groups, including crocodilians, turtles, fishes, and sharks, indicate a similar composition to other Sao Khua Formation communities in northeastern Thailand. The Sao Khua vertebrate assemblage exhibits the taxonomic diversity of dinosaur fauna and is currently the best-documented assemblage in the Early Cretaceous of Southeast Asia. The Aptian–Albian Khok Kruat Formation, however, yields less diverse vertebrates. They are represented by freshwater sharks, crocodilians, and spinosaurid theropods. This may be due to sampling bias, environmental, or taphonomic conditions. This study provides the basis for future paleontological exploration and research of Mesozoic vertebrates in northeastern Thailand.

During recent years, different studies have focused on characterising plant diversities in the Carboniferous environments of the Variscan Foreland. One of these areas, the Nord-Pas-de-Calais Coalfield, has a Namurian–Westphalian sequence that has historically yielded abundant evidence of vegetation change, but to date, little attention has been paid to its macrofloral diversity dynamics. Here we show, for the first time, a comprehensive characterisation of the diversity changes and macroevolutionary patterns from this coalfield. The results show evidence of low levels of species richness during the Namurian, followed by an exponential diversification at the base of Westphalian. Duckmantian–Bolsovian species diversity continues to progressively increase, suggesting relatively stable conditions at that time. Maximum species richness is observed at the mid-Bolsovian followed by a major depletion during the Asturian. Overall, this pattern is quite similar to that seen in other parts of the Variscan Foreland. However, we see Nord-Pas-de-Calais vegetation diversified earlier than those in the British parts, probably because the dynamics of marine incursions and lacustrine conditions delayed its development in the latter areas. Furthermore, we also see the Asturian decline of the Nord-Pas-de-Calais coal swamp occurred later than in other basins, such as in the Pennines, Ruhr, and South Wales. This scenario suggests that the collapse of this biome was probably caused by increased sediment influx and reduced subsidence, resulting from the northwards migration of the Variscan Mountains. This further supports other studies in Europe advocating that climate change was at most only a subsidiary factor in the collapse of the Pennsylvanian coal swamp biomes.

Whether East Asian relict plants have recently taken refuge in their extant ranges or have long been inhabitants in those areas remains uncertain due to insufficient fossil records. Here, we report well-preserved new fossil fruit valves of an East Asian relict genus, Craigia, from the late Eocene of Southwest China, in its extant geographic range. The front projection of these fruit valves has a vertical crease in the middle and pinnate veins, whereas their back projection possesses a stout vascular bundle in the middle separating two flask-shaped locules. Morphological comparisons suggest the placement of these fruit valves within the fossil species, C. oregonensis. Based on recent fossil records, Craigia possibly originated in the high latitudes of Northeast Asia during the Paleocene. It migrated to Southwest China by passing through Central Asia and Tibet when the climate in these areas was warm and wet during the early Paleogene. Our finding of Craigia fruit valves in Southwest China suggests that the genus arrived in and has inhabited its extant geographical range, at least since ∼34 million years ago (late Eocene).

The long-lost mammal fauna from Gravitelli (Messina, Sicily, Italy) represents one of the most important records for investigating faunal dynamics during the Late Miocene of the Mediterranean, although it is unfortunately only known from descriptions carried out in the early 1900s, as the original collection was lost during the Messina Earthquake of 1908. Gravitelli suids have been referred to Propotamochoerus sp. after the redescription of the casts of two specimens that survived to the present day. However, there is further material that has not been considered, which makes that of Gravitelli one of the most abundant samples of Late Miocene suids from Italy, with a minimum number of four individuals represented. A reappraisal of all Gravitelli suids allows to ascribe them to Propotamochoerus provincialis (Suinae, Dicoryphochoerini), following a comparison with related Late Miocene to Pliocene species from Eurasia. Moreover, the re-examination of the geological setting of the locality reveals that the mammal fauna of Gravitelli occurred well below the pre-evaporitic deposits of the Tripoli Formation, whose base is dated in Sicily at ∼7 Ma. Therefore, Gravitelli fauna either dates to the late Tortonian or, at most, to the earliest pre-evaporitic Messinian, corresponding to MN 11 or MN 12 in terms of mammal biochronology. This implies that the occurrence of P. provincialis at Gravitelli is the earliest in Italy and that emerged land masses connected Sicily with the European mainland earlier than 7 Ma. Available dates support a diachronous dispersal of Propotamochoerus in western Europe during the Turolian, being first known from the Balkans ∼8.3 Ma, then from Gravitelli prior to 7 Ma, and then from the Iberian Peninsula since ∼6.2 Ma. A similar pattern is known for Mesopithecus (Cercopithecidae). Although often discussed in light of its potential significance for Afro-Eurasian dispersals, only a fraction of the mammal fauna of Gravitelli has been reconsidered systematically. Notwithstanding the necessity of such dedicated studies, the faunal elements identified so far have an almost entirely European character and no species is shared with Cessaniti (Calabria), despite the two faunas have often been considered part of a paleobioprovince documenting a connection between southern Italy and northern Africa. At Gravitelli, the only species of African origin is the endemic hippo Hexaprotodon? siculus, but the extensive fossil record of insular hippopotamids testifies to their ability to colonize islands even in the absence of land bridges. Gravitelli hippos are nonetheless noteworthy, as the revised age of the site implies that they represent the earliest hippopotamids known outside Africa.

The Eocene of Collio (easternmost Friuli-Venezia Giulia, northeastern Italy) contains rich larger foraminiferal assemblages mainly dominated by nummulitids of genera Nummulites and Assilina. Herein, we document, by typological and biometric approaches, upper Ypresian to lower Lutetian taxa, dated by an integrated biostratigraphy combining the Shallow Benthic Zones (SBZ) with the nannofossil biozones. A total of seven species of Alveolina, 12 species of Assilina and 33 of Nummulites are described (in Appendix A), some of them left in open nomenclature. The larger foraminiferal assemblages indicate that all the collected samples are assignable to SBZ12 and SBZ13 and their high diversity suggests high resilience of these shallow-water taxa after the Early Eocene Climate Optimum warming event. The occurrence of the calcareous nannofossil Blackites inflatus together with Alveolina violae Nummulites friulanus, N. campesinus, N. quasilaevigatus, Assilina maior maior and A. cuvillieri, typical SBZ12 markers, suggests that SBZ12 extends at least to the basal Lutetian, thus the SBZ12/13 boundary occurs in the lowermost Lutetian instead of at the Ypresian/Lutetian transition.

The study of past pathologies by means of quantitative reports is an underexplored approach to deal with the biology and ecology of extinct taxa. In the present study, we assessed the prevalence rate of primary osteoarthritis in a large sample of Prolagus sardus (Mammalia, Lagomorpha) from Medusa Cave (also known as Grotta Dragonara, Sardinia, Italy; Late Pleistocene) to shed light on the evolutionary history of small mammals under isolation regimes. The hip and knee joints of 246 femora were examined grossly, microscopically, and using advanced radiology, recording essential biological features such as age or weight. We noted that 27.7% of skeletally mature sample had degenerative disorder of the joints, with higher frequency in adults (p-value < 0.05), regardless of their body mass (p-value > 0.05). Histologically, affected joints displayed changes in subchondral plate potentially reflecting adaptive modeling. Our analysis revealed ageing (the extended lifespan) as the main driver of this prevalence rate, whereas mechanical factors (caused by a particular lifestyle) were considered of significantly lesser importance. Our results provide additional empirical support to the analytical framework of life history theory from a new perspective, according to which, under low extrinsic mortality regimes, selection should favor slow-strategies (extended lifespan) in small-sized mammals.