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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.

We describe a new species of Cybocephalidae (Coleoptera) from Ethiopian Miocene amber, Pastillus aethiopicus n. sp. This is the second beetle species discovered in that fossiliferous amber deposit. It is the fourth species described in the extant genus Pastillus Endrödy-Younga and the first fossil species discovered. Pastillus is reviewed, the species diagnosed, listed, keyed, and distribution data recorded. Additionally, checklists of fossil Cybocephalidae, and African Cybocephalidae fauna are provided.

In the present paper we trace the patterns of convergent evolution of encrusting calcareous polychaetes and tentaculitoids with respect to the morphology and function of their tubes. Both clades have morphologically similar tubes. Six of the eight basic morphotypes of encrusting tubeworms occur both in calcareous polychaetes and in tentaculitoids. All six encrusting tentaculitoid tubeworm morphotypes distinguished have analogues among serpulid and sabellid polychaetes. Both tentaculitoids and polychaetes with calcareous tubes have a similar plesiomorphic morphotype, which is characterized by substrate parallel, irregular growth away from the initial point of encrustation. Dominance of similarities in the order of evolution of morphotypes in the calcareous tubeworms indicates that despite genetic differences, ecological similarities (suspension feeding) and similarities in the tube material (calcareous), as well as body plan (worm-like) had a strong control over the evolution of calcareous tubeworms. The calcareous tubeworm life modes likely appeared in the order of increasing dependence on the type of substrate. In general, possible antipredatory strategies (spines, keels, cryptic and endobiotic mode of life) of calcareous tubeworms are evolutionarily old. The plesiomorphic general hard substrate encrusters are evolutionarily the most successful and have the longest stratigraphic range both in tube-dwelling polychaetes and tentaculitoids. Innovations, such as attachment of the tube by basal projections were developed in some microconchid tentaculitoids but not in calcareous polychaetes; budding tubes occur in both taxa, however, in microconchid tentaculitoids it was a brief evolutionary event, whereas in polychaetes such pseudocolonies have a long stratigraphic range. The ability to live in brackish and fresh waters by some tentaculitoids and tube-dwelling polychaetes seems not to be associated with any particular tube morphotype.

Bromalites (coprolites, regurgitalites and consumulites) are trace fossils that preserve valuable information on their producers’ diet and feeding behaviors. Here, we report a compact skeletal mass from the Middle Triassic Xingyi Fauna of Dingxiao, Xingyi City, Guizhou Province, South China through multiple analytical methods. Using micro-CT scans, we provide 3D reconstruction of two vertebral arches, four coracoids, three ribs of three kinds, four humeri including one male and three female ones, five scapulae including two right one and three left ones of different sizes, which are inferred to be from at least three individuals of Keichousaurus hui. Bone aggregates of multiple individuals, associated with less gastric etching on bone surfaces and the absence of a phosphatic and organic matrix surrounding the bones as revealed by microstructural and chemical analysis respectively, suggest that this bone mass is a regurgitalite rather than a coprolite. The vertebrate fossils reported from the regurgitalite-bearing strata suggest that the best candidate for the potential producer of the regurgitalite are the near-shore sauropterygians Nothosaurus or Lariosaurus. The discovery of a Keichousaurus-bearing regurgitalite shed new insights on the feeding behaviors of Middle Triassic marine reptiles and the paleoecology of the Xingyi Fauna.