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New caenagnathid dinosaur specimens from the upper Aguja Formation of West Texas comprise the most complete examples yet described from southern North America. Two individuals are represented. Osteohistology indicates that both were mature at their times of death. Although they share no overlapping elements, the two individuals are separated by overall body size, paleohabitat, and stratigraphic position and so they almost certainly represent different species. One individual consists of a partial hindlimb, but exhibits too few (3) characters to be phylogenetically informative and is, therefore, referred to an indeterminate caenagnathid – possibly one of two species previously recognized in coastal facies of the Aguja Formation. The second individual is more complete. It was recovered higher in section from more inland fluvial paleoenvironments and preserves fragmentary elements from throughout the postcranial skeleton. A histology-based growth model – the first for a caenagnathid – indicates that the second individual required at least five years to approach fully adult size. However, only 11 character states could be derived from its preserved remains. Phylogenetic analyses found this specimen deeply nested within Caenagnathidae, but were otherwise inconclusive and so it, too, is referred to an indeterminate caenagnathid. Nevertheless, several combined morphologies (e.g., absence of cervical epipophyses, dorsoventral depth of the hypapophysis on the second cervicodorsal vertebra, and greater trochanter of the femur only weakly separated from the femoral head) implies that the second individual represents an unknown species. One critical aspect of both specimens is that they provide significant new comparative material representing the sparse ‘southern’ caenagnathid record.

Helmet-like small shelly fossils from the Cambrian Fortunian Stage of South China are a class of morphological taxa with uncertain affinities. Here, we redefine the genera Amoebinella and Huizenodus and consider Huizenodus oligaspinosus to be a senior synonym of Amoebinella echinata. In addition, we report two compound fossils of H. oligaspinosus for the first time from the Fortunian Zhangjiagou Lagerstätte in southern Shaanxi. Their multi-branched, dendritic, rigid structure is similar to the skeletons in several groups of colonial anthozoans, and thus, H. oligaspinosus may represent the skeletal structure of an ancestral anthozoan. H. oligaspinosus could have further constructed its skeleton by producing secondary individuals from the main branches or the sub-branches of the primary individuals to accommodate more polyps.

Cinnamomum Schaeffer (avocado, family Lauraceae), commonly known as cinnamon tree, is a highly diverse, economically important evergreen element of tropical and subtropical regions of the world. In the present work, several compressed leaf remains similar to modern leaves of Cinnamomum are recovered from the lower part of the Siwalik strata (middle Miocene) of Darjeeling foothills, eastern Himalaya. The fossil specimens are characterized by an elliptic to ovate lamina, acute to short acuminate apex, round to acute base, basal as well as suprabasal acrodromous type of primary venation, and anomocytic type of stomata. Based on leaf architecture (macro- and micromorphological features) and using leaf epidermal anatomy, these Siwalik fossil leaves are confidently assigned to the genus Cinnamomum and are recognized as a new species: C. miocenicum Mahato, Hazra et Khan. The evidence of current Siwalik specimens and earlier-reported fossil species similar to thermophilic Cinnamomum in appreciable numbers from other Siwalik localities (Darjeeling, Uttarakhand, and Nepal) suggests that Cinnamomum was a common Siwalik element, pointing toward the existence of tropical, warm and humid climate conditions during the Siwalik sedimentation time. This conclusion is also supported by epifoliar fungal remains recovered from cuticular fragments of this lauraceous taxon. This finding also represents an essential source of data for understanding Cinnamomum’s evolution and deep time diversification. We review in detail the biogeographic history and suggest possible migratory routes of the genus from an Asian perspective.

Problems surrounding the identification and systematics of taxa belonging to the trilobite family Ellipsocephalidae have been discussed for several decades. The ellipsocephalid genus Strenuaeva is revised herein on the basis of material from Spain, including the type material of the identified species together with newly collected specimens from the Ossa-Morena Zone and the Iberian Chains. Two species are recognized as valid for these regions: S. sampelayoi and S. incondita. The species ‘S. melendezi’ and ‘Ellipsostrenua alanisiana’ from Spain, as well as ‘S. marocana’ from Morocco, are considered junior synonyms of S. sampelayoi. Previous assignment of the Spanish species to Issafeniella is rejected. The abundant available material of S. sampelayoi made it possible to evaluate the taphonomical role in the preservation of some characters and to recognize intraspecific variability similar to that described in S. inflata from Baltica, reinforcing its assignment to Strenuaeva. Biostratigraphically, Strenuaeva ranges from uppermost Cambrian Stage 3 to uppermost Cambrian Stage 4. In Iberia, it is restricted to the middle Marianian in the Ossa-Morena Zone, whereas it is known from the lowermost middle Marianian to the lowermost upper Marianian in the Iberian Chains. Strenuaeva is known from Baltica (Scandinavia and Holy Cross Mountains, Poland), Iberia (Spain), Morocco and, possibly, western Avalonia (Newfoundland), hence being a characteristic genus of the Acadobaltic faunal Province.

This study documents palynomorph assemblages from the Oligocene through the Early Miocene, across the significant Warm-house to Cool-house transition, using a subsurface section from the AG-5 well, north Western Desert of Egypt. Although the Paleogene and Neogene strata occupied a large area of the land, little about vegetation and ecosystem processes that shaped the climate and biodiversity during this time window is known. Here, based on a comprehensive palynological analysis of the Oligocene to Early Miocene Dabaa and Moghra formations encountered in the AG-5 well, we show that the studied area was characterized by a humid tropical to subtropical climate during the Oligocene-Miocene time interval. The obtained results provide clear evidence of the poorly known Paleogene-Neogene ecosystem in North Africa. In terms of palynostratigraphical framework, three palynozones covering the late Oligocene-Early Miocene interval are recognized. Moreover, the recovered palynomorphs inferred a deposition of the Dabaa Formation under a normal marine, inner shelf to littoral environment. However, for the basal part of the Moghra Formation, a deposition in an offshore marine environment, outer shelf (high sea level, 100–200 m depth) is assumed, whereas a deposition in shallow coastal lagoons, estuary, or delta environment (low sea level) is presumed for its uppermost part.

Trace fossils can illustrate important palaeobiological interactions within a fossil assemblage that body fossils do not record. A group of trace fossils that showcase feeding ecology, and evidence of predation, are coprolites. Shelly coprolites are useful for documenting records of durophagous predators or scavengers within a substrate. To expand the record of these traces from the lower Paleozoic, here we present 12 shelly coprolites from the Late Ordovician (Katian) Bohdalec Formation of the Czech Republic. These coprolites contain abundant Onnia superba (Bancroft, 1929) fragments with marked breakages across exoskeletal sections. Rarer evidence for gastropods, bivalves, crinoid debris, and another indeterminate shelly material are also observed within the coprolites. While the producer cannot be irrevocably determined, possible options are explored. We propose that larger, co-occurring trilobites and predatory cephalopods likely made the majority of coprolites. Furthermore, large unbiomineralised arthropods, such as phyllocarids and eurypterids are highlighted as possible producers. Continued examination of these trace fossils will highlight when and where similar interactions between trophic levels had occurred.

The Late Pleistocene small mammal fauna from Agios Georgios Cave (Kilkis, Central Macedonia, Greece) is examined, resulting in the identification of 14 species of Chiroptera, Rodentia and Lagomorpha. The palaeoenvironment of the area around the cave seems to have been a relatively arid, steppe-like plain with sparsely-wooded patches. There was also a permanent or temporary water body near the cave. The palaeoclimate of the region was colder than today, but rather warm compared to more northern parts of Europe, which were strongly affected by the Last Glacial Maximum.

The end-Triassic is characterized by a significant biotic crisis in both marine and terrestrial realms. However, terrestrial records in eastern Tethys are relatively limited, especially in eastern China. The Fanjiatang Formation represents the Upper Triassic sequence in southern Jiangsu and Anhui provinces of eastern China, yielding a rich plant and bivalve fossil record. The present study provides the first detailed palynological investigation for the Upper Triassic of Nanjing area, eastern China. Six of twenty processed palynological samples are productive, and more than 70 terrestrial spore and pollen fossil taxa were identified. A palynological assemblage, namely, the Concavisporites–Dictyophyllidites–Kyrtomisporis–Classopollis Assemblage was established, characterized by abundant fern spores, mainly including Concavisporites, Dictyophyllidites and Kyrtomisporis, and much less abundant gymnosperm pollen grains (important taxa include Alisporites, Chasmatosporites, and Classopollis), indicating a Late Triassic Norian–Rhaetian age. In conjunction with previously reported macro-plant data, the palynofloral analysis reveals a vegetation dominated by ferns, with diverse cycadophytes, less abundant lycophytes, bryophytes, equisetales, ginkgophytes and seed ferns, and a few conifers. Paleovegetation and semiquantitative palynological analysis permit a paleoecological interpretation, suggesting a lowland groundcover-dominated vegetation under (sub)tropical warm and humid climate in Nanjing area during this time interval. More detailed palynological and macro-plant data through the whole Upper Triassic in this region are necessary in the future to better reveal the Late Triassic paleoecological settings and variations on land prior to the end-Triassic mass extinction in eastern Tethys.

Macaronichnus is a key trace fossil in palaeoceanographic, palaeoclimatic, and petroleum exploration research. Small ichnosubspecies such as Macaronichnus segregatis segregatis, M. s. lineiformins, M. s. maeandriformis and M. s. spiriformis, typically occur in wave-dominated foreshore sands where large M. s. degiberti was never found. The latter shows a wide environmental distribution, occurring in sandy deposits of tidal channels, tidal bar sand sandridges, tidal-flat sand sheets, shorefaces, bioturbated sandy shelf, shelf storm-sheets, shelf sand ridges, and upper slopes. Small M. segregatis and large M. s. degiberti have not been observed to date due the ecological segregation of the tracemakers. An abundant record of large M. s. degiberti in a Tortonian (Late Miocene) mixed carbonate-siliciclastic unit from the Betic Cordillera (southern Spain) has been studied. Occurrence of M. s. degiberti is the result of the interaction of tidal and waves, storm influenced environment determining high-energy conditions and associated palaeoenvironmental parameters as shifting substrates, organic matter availability, and oxygenated pore and bottom-waters. Locally, associated to M. s. degiberti appear small, sinuous traces infilled by light material that were originally assigned to M. s. maeandriformis, and very rare M. s. spiriformis. However, the absence of the typical rim of Macaronichnus avoid a conclusive assignment. The coexistence of both small traces (?M. s. maeandriformis) and large M. s. degiberti is identified in the deposits underlying mudstone layers, revealing the importance of mud deposition during tidal slack water intervals or linked to fluid mud events favouring the co-occurrence of the trace makers of both Macaronichnus ichnosubespecies. This fact would have significant palaeobiological and palaeoecological implications, and could be the first record of both ichnosubspecies in the same intervals.

Squamate faunas from the MN 1–3 intervals (earliest Miocene) are scarcely documented from the European continent. I here describe squamate faunas from two French localities – Montaigu-le-Blin (MN 2) and Crémat (MN 3), the latter being the youngest locality of the Phosphorites du Quercy. The palaeobiodiversity of squamates from these sites is low relative to the faunas described from coeval localities of Amöneburg (MN 2) in Germany and Merkur-North (MN 3) in the Czech Republic. The beginning of the Miocene represents the temporary return to a paratropical humid climate after the relatively cool and dry Oligocene, and the Montaigu and Crémat materials provide previously undocumented components of herpetofaunas and their changes during this crucial time interval in France. The importance of fossil squamates from the area of the Phosphorites du Quercy is therefore highlighted for the beginning of the Miocene as well as the better known Eocene-Oligocene sites. The lizard material of Montaigu includes lacertids and blanids, the latter being represented by Blanus cf. gracilis, one of the oldest records of the genus. Moreover, it shows a higher spatial and temporal distribution of this amphisbaenian species during the Early Miocene than previously known. The material from Crémat consists of few elements which can be allocated to anguids and potentially to lacertids. Detailed figures of the specimens are provided through the means of both photography and micro-CT scanning.