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The osteology of Luxembourgichthys friedeni (Delsate, 1999) gen. nov. from the marine Toarcian (Grandcourt Formation, Lower Jurassic) of Belgium and the Grand Duchy of Luxembourg is studied in detail. This fossil teleost fish was initially assigned to Pholidophorus, a genus that recently received an emended diagnosis (Arratia, 2013). The cranial characters of L. friedeni considerably differ from those that now define Pholidophorus and the Pholidophoridae, excluding its attribution to both this genus and this family. In L. friedeni the posttemporal fossa is completely located on the lateral face of the braincase and not on the rear of the skull as usual. Such a position is unique among “Pholidophoriformes” and justifies the peculiar generic status of this taxon. L. friedeni possesses three specialized characters (a beryciform foramen piercing the anterior ceratohyal, arcocentra associated to the chordacentra and ovoid scales devoid of the peg-and-socket system) suggesting it occupies a position crownward of most “pholidophoriforms”, closer to Jurassic and younger teleosts with cycloid scales.

The production of species checklists is fundamental to setting baseline knowledge of biodiversity across the world and they are invaluable for global conservation efforts. The main objective of this study is to provide an up-to-date extensive checklist of the ants of the Democratic Republic of Congo (DRC), the largest country in sub-Saharan Africa, based on available literature to serve as a foundation for future research and ant faunistic developments. We gathered the literature available to us, most of it compiled from the Global Ant Biodiversity Informatics (GABI) Project and treated the data to province level when possible. We also offer insight into who, when and where contributions have emerged to the current knowledge of the ants of the DRC and each of its 26 provinces. The current list is restricted to valid species and subspecies, discarding morphospecies and some misidentified taxa. The list comprises eight subfamilies, 64 genera and 736 species, the highest species diversity for a country located within the Afrotropical realm.

L’une des toutes premières ammonites à coquille presque oxycône observée dans les séries fossilifères après la crise faunique de la limite Trias/Jurassique est décrite. Elle provient du Sinémurien inférieur (chronozone à Semicostatum ou à Turneri) de Bourgogne (Mavilly-Mandelot, Côte-d’Or, France). Cette nouvelle forme, Oxyarietites boletzkyi n. gen., n. sp., possède une coquille involute, comprimée et carénée dont le type clairement suboxycône est nouveau pour le Sinémurien inférieur. En raison de son aire ventrale carénée, ce taxon se rattache probablement à la super-famille des Arietitoidea Hyatt, 1875 sensu Guex (1995) mais son attribution familiale est incertaine et son origine évolutive reste énigmatique. Outre son intérêt taxonomique, cette découverte est importante car elle pose le problème de la valeur adaptative des caractères liés à la géométrie des coquilles d’ammonites. Il est actuellement admis que les coquilles involutes, comprimées et carénées de type suboxycône et oxycône favorisent significativement l’hydrodynamisme et donc la mobilité des espèces qui les possèdent. Il est surprenant que l’acquisition de ce probable avantage adaptatif n’ait pas favorisé l’implantation au sein des peuplements du nouveau taxon, qui reste une forme rare. Dans tous les cas, la découverte d’O. boletzkyi n. gen., n. sp. rajeunit d’environ 2 millions d’années la mise en place des morphologies oxycônes au cours de la phase de reconstitution de la biodiversité post-crise Trias/Jurassique. Oxyarietites boletzkyi n.gen., n. sp., a new genus and species of ammonite for the Lower Sinemurian of Burgundy (France): a rare forerunner of the oxycone morpho­logies for the Jurassic. One of the very first quasi-oxycone ammonites following the Triassic/Jurassic boundary crisis is described. It was collected from the fossiliferous Lower Sinemurian (Semicostatum or Turneri Chronozone) strata of Burgundy (Mavilly-Mandelot, Côte-d’Or, France). The new taxon, Oxyarietites boletzkyi n. gen., n.sp., possesses an involute, compressed and keeled shell of suboxycone morphology, a shell type previously unknown for the Lower Sinemurian. The discovery makes younger by about 2 Ma the emergence of keeled (sub)oxycone shells following the Triassic/Jurassic boundary crisis. Its obviously keeled ventral area allows a probable assignation to the Arietitoidea Hyatt, 1875 sensu Guex (1995) superfamily, but family level assignation and its evolutionary origin remain obscure. Although, it is generally accepted that involute, compressed and keeled suboxycone and oxycone ammonite shells possess the best hydrodynamical abilities and mobility, the acquisition of this probable adaptive advantage in O. boletzkyi n. gen., n. sp. does not go together with abundancy in the fossil record.

The distribution of the black rat (Rattus rattus) has been heavily influenced by its association with humans. The dispersal history of this non-native commensal rodent across Europe, however, remains poorly understood, and different introductions may have occurred during the Roman and medieval periods. Here, in order to reconstruct the population history of European black rats, we first generate a de novo genome assembly of the black rat. We then sequence 67 ancient and three modern black rat mitogenomes, and 36 ancient and three modern nuclear genomes from archaeological sites spanning the 1st-17th centuries CE in Europe and North Africa. Analyses of our newly reported sequences, together with published mitochondrial DNA sequences, confirm that black rats were introduced into the Mediterranean and Europe from Southwest Asia. Genomic analyses of the ancient rats reveal a population turnover in temperate Europe between the 6th and 10th centuries CE, coincident with an archaeologically attested decline in the black rat population. The near disappearance and re-emergence of black rats in Europe may have been the result of the breakdown of the Roman Empire, the First Plague Pandemic, and/or post-Roman climatic cooling.

The main excavations at the Troisième caverne of Goyet in Belgium were conducted by Edouard Dupont in 1868 who identified Palaeolithic human occupations later attributed to the Middle and Upper Palaeolithic. These are represented by an archaeologi- cal record that spans the Mousterian, Lincombian-Ranisian-Jerzmanowician, Aurignacian, Gravettian, and Magdalenian, and then extends into the Neolithic and historic periods. Due to the lack of detailed documentation of the excavated materials, their asso- ciation to a specific chronocultural context has been challenging. Morphometric and taphonomic analyses, combined with direct radiocarbon dating as well as isotopic and genetic analyses, were used to assign human remains to either late Neanderthals or an- cient modern humans from different chronocultural groups. In 2016 the first palaeogenetic investigation of Neanderthal specimens from Goyet was published [1]. Taxonomic assignment was confirmed by performing hybridization capture of the mitochondrial DNA (mtDNA) and later inspecting diagnostic mutations at nucleotide positions that distinguish modern humans from Nean- derthals. Moreover, a phylogenetic reconstruction placed seven nearly complete mtDNA sequences from Goyet within the diver- sity of late Neanderthal mtDNA. An around two-fold coverage nuclear genome was later sequenced from one of those individuals (Goyet Q56-1) [2], revealing a high genetic similarity to other late Neanderthals that is well correlated to their geographical dis- tance. Analyzing modern human remains retrieved at Goyet, mtDNA genomes were initially reported for two specimens directly dated to the Aurignacian, five to the Gravettian, and one to the Magdalenian [3]. Aurignacian-related individuals were particu- larly intriguing as they were found to carry mtDNA haplogroup M, which is almost entirely absent in present-day Europeans. For Gravettian- to Magdalenian-related individuals, the shift from U2/U5 to U8 haplogroups was detected locally - as in other regions of Central Europe - likely influenced by the genetic bottleneck during the Last Glacial Maximum (LGM). Furthermore, nuclear sequences of five modern human individuals from Goyet were produced through genome-wide targeted enrichment [4] revealing local replacement between Aurignacian- and Gravettian-related populations. However, the genetic component associated with a 35,000-year-old individual (Goyet Q116-1) reappeared after the LGM, first in Spain and then in other European regions includ- ing in a Magdalenian-related individual from Goyet (Goyet Q-2). This individual was later found to be the best proxy for a genetic component that was largely displaced in Europe from around 14,000 years ago onwards while surviving in high proportion among Mesolithic individuals from Iberia [5]. Here we present new palaeogenetic data of Neanderthal and modern human individuals from this iconic site. First, we expand the molecular taxonomic identifications with three additional Neanderthal specimens and reconstruct their partial mtDNA genomes. Those confirm the general picture of a limited genetic diversity for late Neanderthals, which is also apparent among the Goyet Neanderthals. Second, working on modern human remains, we produced new mtDNA and nuclear data from four Gravettian specimens. They belong to mtDNA haplogroups U2 and U5, further extending the observa- tion of both mtDNA types being largely present in pre-LGM Europe. Moreover, their nuclear genomes provide additional evidence for the genetic affinity between Gravettian-related groups across Europe, from the present-day regions of the Czech Republic to Belgium and Southern Italy. In conclusion, the deep temporal range covered by the human remains from the Troisième caverne of Goyet provides the unique opportunity to describe within a single archaeological site the major genetic transformations that took place in Europe throughout the Middle and Upper Palaeolithic.